Dr. Hank Liers, PhD vitamin B12 B-12 cobalamin methylcobalaminI previously wrote METHYLATION CYCLE, GENETICS, B VITAMINS in which I considered in-depth how the Methylation Cycle functions, how genetics affect metabolic pathways, and how B vitamins (including vitamin B12, folate, vitamin B6, and vitamin B2) are used in Methylation Cycle pathways. In today’s article, I take an in-depth view of what you need to know about vitamin B12, including the effects of not having sufficient amounts of Vitamin B12 in the body.

Vitamin B12 is one of eight B vitamins. It is the largest and most structurally complicated vitamin. It consists of a class of chemically related compounds (vitamers), all of which show physiological activity. It contains the biochemically rare element cobalt positioned in the center of a chemical ring structure.

Vitamin B12 (also called cobalamin) is a water-soluble vitamin that is involved in the metabolism of every cell of the human body. It is a cofactor in DNA synthesis, and in both fatty acid and amino acid metabolism. It is particularly important in the normal functioning of the nervous system via its role in the synthesis of myelin and in the maturation of developing red blood cells in the bone marrow.

vitamin B12

Vitamin B12 contains the biochemically rare element cobalt positioned in the center of a chemical ring structure.


Vitamin B12 deficiency is thought to be one of the leading nutritional deficiencies in the world. An extensive 2004 study showed that deficiency is a major health concern in many parts of the world, including the North America, Central and South America, India, and certain areas in Africa. It is estimated that 40 percent of people may have low levels of vitamin B12.

Vitamin B12 affects your mood, energy level, memory, nervous system, heart, skin, hair, digestion and more. It is a key nutrient regarding adrenal fatigue and multiple metabolic functions including enzyme production, DNA synthesis, and hormonal balance.

Because of vitamin B12’s extensive roles within the body, a vitamin deficiency can show up in many different symptoms, such as chronic fatigue, mood disorders such as depression, chronic stress, and low energy.


The only organisms to produce vitamin B12 are certain bacteria and archaea. Some of these bacteria are found in the soil around the grasses that ruminants eat. They are taken into the animal, proliferate, form part of their gut flora, and continue to produce vitamin B12.

Products of animal origin such as beef (especially liver), chicken, pork, eggs, dairy, clams, and fish constitute the primary food source of vitamin B12. Older individuals and vegans are advised to use vitamin B12 fortified foods and supplements to meet their needs.

vitamin B12 salmon

Salmon is a good source of Vitamin B12

Commercially, Vitamin B12 is prepared by bacterial fermentation. Fermentation by a variety of microorganisms yields a mixture of methylcobalamin, hydroxocobalamin, and adenosylcobalamin. Since multiple species of propionibacterium produce no exotoxins or endotoxins and have been granted GRAS status (generally regarded as safe) by the United States Food and Drug Administration, they are the preferred bacterial fermentation organisms for vitamin B12 production.

Methylcobalamin and 5-deoxyadenosylcobalamin are the forms of vitamin B12 used in the human body (called coenzyme forms). The form of cobalamin used in many some nutritional supplements and fortified foods, cyanocobalamin, is readily converted to 5-deoxyadenosylcobalamin and methylcobalamin in the body.

Hydroxocobalamin is the direct precursor of methylcobalamin and 5-deoxyadenosylcobalamin. In mammals, cobalamin is a cofactor for only two enzymes, methionine synthase (MS) and L-methylmalonyl-coenzyme A mutase (MUT).

Unlike most other vitamins, B12 is stored in substantial amounts, mainly in the liver, until it is needed by the body. If a person stops consuming the vitamin, the body’s stores of this vitamin usually take about 3 to 5 years to exhaust. Vitamin B12 is primarily stored in the liver as 5-deoxyadenosylcobalamin, but is easily converted to methylcobalamin.


Vitamin B12, bound to protein in food, is released by the activity of hydrochloric acid and gastric protease in the stomach. Intestinal absorption of vitamin B12 requires successively three different protein molecules: Haptocorrin, Intrinsic Factor and Transcobalamin II. If there are deficiencies in any of these factors absorption of Vitamin B12 can be seriously decreased.

When vitamin B12 is added to fortified foods and dietary supplements, it is already in free form and, thus, does not require the separation from food protein step. Free vitamin B12 then combines with intrinsic factor, a glycoprotein secreted by the stomach’s parietal cells, and the resulting complex undergoes absorption within the distal ileum by receptor-mediated endocytosis.

Approximately 56% of a 1 mcg oral dose of vitamin B12 is absorbed, but absorption decreases drastically when the capacity of intrinsic factor is exceeded (at 1–2 mcg of vitamin B12).

Vitamin B12 – 5 mg methylcobalamin sublingual lozenge

Vitamin B12 – 5 mg Methylcobalamin sublingual lozenge.


Vitamin B12 deficiency can be difficult to detect, especially since the symptoms of a vitamin B12 deficiency can be similar to many common symptoms, such as feeling tired or unfocused, experienced by people for a variety of reasons.

Vitamin B12 deficiency is commonly associated with chronic stomach inflammation, which may contribute to an autoimmune vitamin B12 malabsorption syndrome called pernicious anemia and to a food-bound vitamin B12 malabsorption syndrome. Poor absorption of vitamin may be related to coeliac disease. Impairment of vitamin B12 absorption can cause megaloblastic anemia and neurologic disorders in deficient subjects. In some cases, permanent damage can be caused to the body when B12 amounts are deficient.

It is noteworthy that normal function of the digestive system required for food-bound vitamin B12 absorption is commonly impaired in individuals over 60 years of age, placing them at risk for vitamin B12 deficiency.

A diagnosis of vitamin B12 deficiency is typically based on the measurement of serum vitamin B12 levels within the blood. However, studies show that about 50 percent of patients with diseases related to vitamin B12 deficiency have normal B12 levels when tested. This can cause individuals to ignore taking in adequate levels of vitamin B12 with potential serious consequences.


  • Vitamin B12 or cobalamin plays essential roles in folate metabolism and in the synthesis of the citric acid cycle intermediate, succinyl-CoA.
  • Vitamin B12 deficiency is commonly associated with chronic stomach inflammation, which may contribute to an autoimmune vitamin B12 malabsorption syndrome called pernicious anemia and to a food-bound vitamin B12 malabsorption syndrome. Impairment of vitamin B12 absorption can cause megaloblastic anemia and neurologic disorders in deficient subjects.
  • Normal function of the digestive system required for food-bound vitamin B12 absorption is commonly impaired in individuals over 60 years of age, placing them at risk for vitamin B12 deficiency.
  • Vitamin B12 and folate are important for homocysteine metabolism. Elevated homocysteine levels in blood are a risk factor for cardiovascular disease (CVD). B vitamin supplementation has been proven effective to control homocysteine levels.
  • The preservation of DNA integrity is dependent on folate and vitamin B12 availability. Poor vitamin B12 status has been linked to increased risk of breast cancer in some, but not all, observational studies.
  • Low maternal vitamin B12 status has been associated with an increased risk of neural tube defects (NTD), but it is not known whether vitamin B12 supplementation could help reduce the risk of NTD.
  • Vitamin B12 is essential for the preservation of the myelin sheath around neurons and for the synthesis of neurotransmitters. A severe vitamin B12 deficiency may damage nerves, causing tingling or loss of sensation in the hands and feet, muscle weakness, loss of reflexes, difficulty walking, confusion, and dementia.
  • While hyperhomocysteinemia may increase the risk of cognitive impairment, it is not clear whether vitamin B12 deficiency contributes to the risk of dementia in the elderly. Although B-vitamin supplementation lowers homocysteine levels in older subjects, the long-term benefit is not yet known.
  • Both depression and osteoporosis have been linked to diminished vitamin B12 status and high homocysteine levels.
  • The long-term use of certain medications, such as inhibitors of stomach acid secretion, can adversely affect vitamin B12 absorption.
  • Vitamin B12 is required for proper red blood cell formation, neurological function, and DNA synthesis.


1. Vitamin B12 is required for proper red blood cell formation, neurological function, and DNA synthesis. Vitamin B12 as methylcobalamin functions as a cofactor for methionine synthase. Methionine synthase (MS) catalyzes the conversion of homocysteine to methionine. Methionine along with ATP is required for the formation of S-adenosylmethionine (SAMe), a universal methyl donor for almost 100 different substrates, including DNA, RNA, hormones, proteins, and lipids.
2. Vitamin B12 as 5-deoxyadenosylcobalamin functions as a cofactor along with L-methylmalonyl-CoA mutase (MUT) to convert L-methylmalonyl-CoA to succinyl-CoA in the degradation of propionate, an essential biochemical reaction in fat and protein metabolism. Succinyl-CoA is also required for hemoglobin synthesis.
Metabolic Pathway


3. Vitamin B12, bound to protein in food, is released by the activity of hydrochloric acid and gastric protease in the stomach. When synthetic vitamin B12 is added to fortified foods and dietary supplements, it is already in free form and, thus, does not require this separation step. Free vitamin B12 then combines with intrinsic factor, a glycoprotein secreted by the stomach’s parietal cells, and the resulting complex undergoes absorption within the distal ileum by receptor-mediated endocytosis. Approximately 56% of a 1 mcg oral dose of vitamin B12 is absorbed, but absorption decreases drastically when the capacity of intrinsic factor is exceeded (at 1–2 mcg of vitamin B12).

4. Pernicious anemia is an autoimmune disease that affects the gastric mucosa and results in gastric atrophy. This leads to the destruction of parietal cells, achlorhydria, and failure to produce intrinsic factor, resulting in vitamin B12 malabsorption. If pernicious anemia is left untreated, it causes vitamin B12 deficiency, leading to megaloblastic anemia and neurological disorders, even in the presence of adequate dietary intake of vitamin B12.

5. Vitamin B12 status is typically assessed via serum or plasma vitamin B12 levels. Values below approximately 170–250 pg/mL (120–180 picomol/L) for adults indicate a vitamin B12 deficiency. However, evidence suggests that serum vitamin B12 concentrations might not accurately reflect intracellular concentrations. An elevated serum homocysteine level (values >13 micromol/L) might also suggest a vitamin B12 deficiency. However, this indicator has poor specificity because it is influenced by other factors, such as low vitamin B6 or folate levels. Elevated methylmalonic acid levels (values >0.4 micromol/L) might be a more reliable indicator of vitamin B12 status because they indicate a metabolic change that is highly specific to vitamin B12 deficiency.

6. Vitamin B12 deficiency is characterized by megaloblastic anemia, fatigue, weakness, constipation, loss of appetite, and weight loss. Neurological changes, such as numbness and tingling in the hands and feet, can also occur . Additional symptoms of vitamin B12 deficiency include difficulty maintaining balance, depression, confusion, dementia, poor memory, and soreness of the mouth or tongue. The neurological symptoms of vitamin B12 deficiency can occur without anemia, so early diagnosis and intervention is important to avoid irreversible damage. During infancy, signs of a vitamin B12 deficiency include failure to thrive, movement disorders, developmental delays, and megaloblastic anemia. Many of these symptoms are general and can result from a variety of medical conditions other than vitamin B12 deficiency.

7. Typically, vitamin B12 deficiency is treated with vitamin B12 injections, since this method bypasses potential barriers to absorption. However, high doses of oral vitamin B12 can also be effective. The authors of a review of randomized controlled trials comparing oral with intramuscular vitamin B12 concluded that 2,000 mcg (I like 5,000 mcg) of oral vitamin B12 daily, followed by a decreased daily dose of 1,000 mcg and then 1,000 mcg weekly and finally, monthly might be as effective as intramuscular administration. Overall, an individual patient’s ability to absorb vitamin B12 is the most important factor in determining whether vitamin B12 should be administered orally or via injection. In most countries, the practice of using intramuscular vitamin B12 to treat vitamin B12 deficiency has remained unchanged.

8. Large amounts of folate can mask the damaging effects of vitamin B12 deficiency by correcting the megaloblastic anemia caused by vitamin B12 deficiency without correcting the neurological damage that also occurs. Moreover, preliminary evidence suggests that high serum folate levels might not only mask vitamin B12 deficiency, but could also exacerbate the anemia and worsen the cognitive symptoms associated with vitamin B12 deficiency. Permanent nerve damage can occur if vitamin B12 deficiency is not treated. For these reasons, folate intake from fortified food and supplements should not exceed 1,000 mcg daily in healthy adults.

Groups at Risk of Vitamin B12 Deficiency

The main causes of vitamin B12 deficiency include vitamin B12 malabsorption from food, pernicious anemia, postsurgical malabsorption, and dietary deficiency. However, in many cases, the cause of vitamin B12 deficiency is unknown. The following groups are among those most likely to be vitamin B12 deficient.

Older adults: Atrophic gastritis, a condition affecting 10%–30% of older adults, decreases secretion of hydrochloric acid in the stomach, resulting in decreased absorption of vitamin B12. Decreased hydrochloric acid levels might also increase the growth of normal intestinal bacteria that use vitamin B12, further reducing the amount of vitamin B12 available to the bodY.

Individuals with atrophic gastritis are unable to absorb the vitamin B12 that is naturally present in food. Most, however, can absorb the synthetic vitamin B12 added to fortified foods and dietary supplements. As a result, the IOM recommends that adults older than 50 years obtain most of their vitamin B12 from vitamin supplements or fortified foods. However, some elderly patients with atrophic gastritis require doses much higher than the RDA to avoid subclinical deficiency.

Individuals with pernicious anemia: Pernicious anemia, a condition that affects 1%–2% of older adults, is characterized by a lack of intrinsic factor. Individuals with pernicious anemia cannot properly absorb vitamin B12 in the gastrointestinal tract. Pernicious anemia is usually treated with intramuscular vitamin B12. However, approximately 1% of oral vitamin B12 can be absorbed passively in the absence of intrinsic factor, suggesting that high oral doses of vitamin B12 might also be an effective treatment.

Individuals with gastrointestinal disorders: Individuals with stomach and small intestine disorders, such as celiac disease and Crohn’s disease, may be unable to absorb enough vitamin B12 from food to maintain healthy body stores. Subtly reduced cognitive function resulting from early vitamin B12 deficiency might be the only initial symptom of these intestinal disorders, followed by megaloblastic anemia and dementia.

Individuals who have had gastrointestinal surgery: Surgical procedures in the gastrointestinal tract, such as weight loss surgery or surgery to remove all or part of the stomach, often result in a loss of cells that secrete hydrochloric acid and intrinsic factor. This reduces the amount of vitamin B12, particularly food-bound vitamin B12, that the body releases and absorbs. Surgical removal of the distal ileum also can result in the inability to absorb vitamin B12. Individuals undergoing these surgical procedures should be monitored preoperatively and postoperatively for several nutrient deficiencies, including vitamin B12 deficiency.

Vegetarians: Strict vegetarians and vegans are at greater risk than lacto-ovo vegetarians and non-vegetarians of developing vitamin B12 deficiency because natural food sources of vitamin B12 are limited to animal foods. Fortified breakfast cereals and fortified nutritional yeasts are some of the only sources of vitamin B12 from plants and can be used as dietary sources of vitamin B12 for strict vegetarians and vegans. Fortified foods vary in formulation, so it is important to read the Nutrition Facts labels on food products to determine the types and amounts of added nutrients they contain.

Pregnant and lactating women who follow strict vegetarian diets and their infants: Vitamin B12 crosses the placenta during pregnancy and is present in breast milk. Exclusively breastfed infants of women who consume no animal products may have very limited reserves of vitamin B12 and can develop vitamin B12 deficiency within months of birth. Undetected and untreated vitamin B12 deficiency in infants can result in severe and permanent neurological damage.

The American Dietetic Association recommends supplemental vitamin B12 for vegans and lacto-ovo vegetarians during both pregnancy and lactation to ensure that enough vitamin B12 is transferred to the fetus and infant. Pregnant and lactating women who follow strict vegetarian or vegan diets should consult with a pediatrician regarding vitamin B12 supplements for their infants and children.

Health Risks from Excessive Vitamin B12

The IOM did not establish a UL for vitamin B12 because of its low potential for toxicity. In Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline, the IOM states that “no adverse effects have been associated with excess vitamin B12 intake from food and supplements in healthy individuals”.

Findings from intervention trials support these conclusions. In the NORVIT and HOPE 2 trials, vitamin B12 supplementation (in combination with folic acid and vitamin B6) did not cause any serious adverse events when administered at doses of 0.4 mg for 40 months (NORVIT trial) and 1.0 mg for 5 years (HOPE 2 trial).

Interactions with Medications

Vitamin B12 has the potential to interact with certain medications. In addition, several types of medications might adversely affect vitamin B12 levels. A few examples are provided below. Individuals taking these and other medications on a regular basis should discuss their vitamin B12 status with their healthcare providers.

Chloramphenicol: Chloramphenicol (Chloromycetin®) is a bacteriostatic antibiotic. Limited evidence from case reports indicates that chloramphenicol can interfere with the red blood cell response to supplemental vitamin B12 in some patients.

Proton pump inhibitors: Proton pump inhibitors, such as omeprazole (Prilosec®) and lansoprazole (Prevacid®), are used to treat gastroesophageal reflux disease and peptic ulcer disease. These drugs can interfere with vitamin B12 absorption from food by slowing the release of gastric acid into the stomach. However, the evidence is conflicting on whether proton pump inhibitor use affects vitamin B12 status. As a precaution, healthcare providers should monitor vitamin B12 status in patients taking proton pump inhibitors for prolonged periods.

H2 receptor antagonists: Histamine H2 receptor antagonists, used to treat peptic ulcer disease, include cimetidine (Tagamet®), famotidine (Pepcid®), and ranitidine (Zantac®). These medications can interfere with the absorption of vitamin B12 from food by slowing the release of hydrochloric acid into the stomach. Although H2 receptor antagonists have the potential to cause vitamin B12 deficiency, no evidence indicates that they promote vitamin B12 deficiency, even after long-term use. Clinically significant effects may be more likely in patients with inadequate vitamin B12 stores, especially those using H2 receptor antagonists continuously for more than 2 years.

Metformin: Metformin, a hypoglycemic agent used to treat diabetes, might reduce the absorption of vitamin B12, possibly through alterations in intestinal mobility, increased bacterial overgrowth, or alterations in the calcium-dependent uptake by ileal cells of the vitamin B12-intrinsic factor complex. Small studies and case reports suggest that 10%–30% of patients who take metformin have reduced vitamin B12 absorption. In a randomized, placebo controlled trial in patients with type 2 diabetes, metformin treatment for 4.3 years significantly decreased vitamin B12 levels by 19% and raised the risk of vitamin B12 deficiency by 7.2% compared with placebo. Some studies suggest that supplemental calcium might help improve the vitamin B12 malabsorption caused by metformin, but not all researchers agree.


FROM: https://academic.oup.com/ajcn/article/71/2/514/4729184
Plasma vitamin B-12 concentrations relate to intake source in the Framingham Offspring Study

The American Journal of Clinical Nutrition, Volume 71, Issue 2, 1 February 2000, Pages 514–522, https://doi.org/10.1093/ajcn/71.2.514


Background: Low vitamin B-12 status is prevalent among the elderly, but few studies have examined the association between vitamin B-12 status and intake.
Objective: We hypothesized that vitamin B-12 concentrations vary according to intake source.
Design: Plasma concentrations and dietary intakes were assessed cross-sectionally for 2999 subjects in the Framingham Offspring Study. The prevalence of vitamin B-12 concentrations <148, 185, and 258 pmol/L was examined by age group (26–49, 50–64, and 65–83 y), supplement use, and the following food intake sources: fortified breakfast cereal, dairy products, and meat.
Results: Thirty-nine percent of subjects had plasma vitamin B-12 concentrations <258 pmol/L, 17% had concentrations <185 pmol/L, and 9% had concentrations <148 pmol/L, with little difference between age groups. Supplement users were significantly less likely than non-supplement-users to have concentrations <185 pmol/L (8% compared with 20%, respectively). Among non-supplement-users, there were significant differences between those who consumed fortified cereal >4 times/wk (12%) and those who consumed no fortified cereal (23%) and between those in the highest and those in the lowest tertile of dairy intake (13% compared with 24%, respectively), but no significant differences by meat tertile. Regression of plasma vitamin B-12 on log of intake, by source, yielded significant slopes for each contributor adjusted for the others. For the total group, b = 40.6 for vitamin B-12 from vitamin supplements. Among non-supplement-users, b = 56.4 for dairy products, 35.2 for cereal, and 16.7 for meat. Only the meat slope differed significantly from the others.
Conclusions: In contrast with previous reports, plasma vitamin B-12 concentrations were associated with vitamin B-12 intake. Use of supplements, fortified cereal, and milk appears to protect against lower concentrations. Further research is needed to investigate possible differences in bioavailability.




What I’d Really Love to Tell You About the Methylation Cycle

Dr. Hank Liers, PhD geneticsI previously published “Homocysteine Genetics – Coenzyme B Vitamins” in which I considered in-depth how homocysteine (an intermediate chemical in the Methylation Cycle) is formed from methionine, how genetics affects the metabolic pathways, and how B vitamins are used in metabolic pathways. I also wrote “Folate Ingredients – Folinic Acid & 5-MTHF” which discussed how coenzyme folate vitamins are far superior to the synthetic folic acid form. In today’s article, I take a broader view of the topic that encompasses the Methylation Cycle, genetics, and B vitamins.


The Methylation Cycle is considered to be one of the most important metabolic pathways in the human body. Its most important function is to provide methyl groups via SAM (S-adenosyl methionine) to hundreds of different body substrates. Methylation is continually occurring in the body, transforming many millions of molecules throughout the body every second. Molecules receive methyl groups, then separate and recombine continuously, transforming and reforming constantly in the ongoing process of life!

As a reminder of the pathways involved in the Methylation Cycle, the following figure provides a flow chart showing the details.


Methylation Cycle

Figure 1. Metabolic Pathways in Methylation Cycle

A key purpose of this cycle is to provide methyl groups (CH3) needed by a broad range of of body functions (over 200 different functions). Examples include:

  1. Influences the genetic expression that parents give their children and helps guide the development of the embryo.
  2. Is needed by the nervous system to produce neurotransmitters and maintain the nerves.
  3. Mobilizes fats and cholesterol so they do not accumulate where they are harmful, such as the arteries and liver.
  4. Regulates hormones, including, estrogen, adrenaline, and melatonin.
  5. Detoxifies harmful chemicals and histamine a prime substance involved in inflammation.
  6. Helps repair damaged proteins in the cells so they can function properly.
  7. Protects the DNA in the genome (genetic code) to reduce the chances of mutation.
  8. Creates antioxidants used in the antioxidant defense system.


The overall flow of the Methylation Cycle begins with dietary methionine (an essential amino acid) which combines with ATP (adenosine triphosphate – body energy) to form SAM (S-adenosyl methionine) – the common cosubstrate involved in methyl group transfers, transsulfuration, and aminopropylation. When SAM transfers a methyl group to a body chemical the residue from this reaction leads to the production of homocysteine.

Homocysteine can be converted in the transsulfuration pathway that requires coenzyme vitamin B6 to produce cysteine, glutathione, taurine, and sulfates. These sulfur containing substances provide important antioxidant protection and detoxification functions in the body.

Homocysteine can be converted back to methionine through the betaine (trimethyl glycine) pathway which requires zinc and magnesium. This pathway also requires dietary betaine or choline which the body can convert into betaine.

Also, homocysteine can be converted back to methionine via the remethylation pathway which requires 5-MTHF, coenzyme vitamin B2 and methylcobalamin (B12).


It is important to understand that each of the pathways described above are able to be executed only in the presence of enzymes (shown in blue boxes in the diagram) created by specific genes in your genetic code. For example, Betaine-Homocysteine S-Methyltransferase (BHMT) is the enzyme required in the betaine pathway, Cystathione Beta Synthase (CBS) is the enzyme required in the transsulfuration pathway, and Methylenetetrahydrofolate Reductase (MTHFR) and Methionine Synthase (MS) are enzymes required in the remethylation pathway.

Assuming that you have perfect genetics (no mutations, SNPs, free radical damage, insertions/deletions, etc.), the proper functioning of these pathways are still subjected to the fact that the required vitamins and minerals (vitamin B6, vitamin B2, Folate, vitamin B12, zinc, magnesium, and betaine) need to be provided by your diet or from supplements for the body to function correctly.

In addition, exposure to high levels of toxins from your environment and high levels of stress require that the nutritional needs will be even higher for the pathways to work properly. For example, exposure to high levels of toxins requires that the transsulfuration pathway be more active possibly reducing the amount of available methionine to support necessary methyl transfer reactions.

For these reasons alone the consensus of knowledgeable practitioners is that you should be eating an organic whole foods diet, taking appropriate nutritional supplements, avoiding and eliminating toxins from food, water, and air (living in a clean environment), and avoiding an unduly stressful life. All of these actions fall into the category of Epigenetics which you generally have control over!! Doing these things alone could significantly balance the functioning of your Methylation Cycle and improve your health.

Unfortunately, few people have perfect genetics which often causes the various pathways in the Methylation Cycle to become imbalanced and unable to correct the dysregulation imposed upon the body. For example, the enzyme MTHFR can have heterozygous (single chromosome) genetic variations in up to 50% of certain populations and homozygous genetic variations (both chromosomes) in 10% or more of certain populations.

Some disorders that researchers have associated with MTHFR genetic variations include:

  • Alzheimer’s disease
  • Asthma
  • Atherosclerosis
  • Autism
  • Bipolar disorder
  • Bladder issues
  • Blood clots
  • Breast problems
  • Chemical sensitivity
  • Chronic fatigue syndrome
  • Down syndrome
  • Epilepsy
  • Fibromyalgia
  • Gastric problems
  • Glaucoma
  • Heart murmurs
  • High blood pressure
  • Irritable bowel syndrome
  • Leukemia
  • Male infertility
  • Methotrexate toxicity
  • Migraines with aura
  • Multiple sclerosis
  • Myocardial infarction
  • Nitrous oxide toxicity
  • Parkinson’s disease
  • Pulmonary embolisms
  • Schizophrenia
  • Stroke
  • Thyroid issues
  • Unexplained neurologic disease
  • Vascular dementia

This extensive list is highly significant and tells us that it is very important to have genetic testing done for the genes/enzymes in the Methylation Cycle pathway. I prefer the BodySync genetic test which evaluates the key Methylation Cycle genes plus many other important genes in a single test.


We are strong believers that everyone should start their nutritional program by eating a balanced, organic, whole foods diet. We have been doing this ourselves for the past 30 years. Unfortunately, only a small percentage of people follow this advice and in most cases this leads to poor nutritional status that does not adequately support the body’s needs. This is especially true with respect to obtaining the nutrients needed to support the Methylation Cycle.

Nine of our family members and associates have taken the BodySync genetic test which evaluates the condition of 45 different enzymes including CBS, MTHFR (2 variations), MTR (related to B12 and 5-MTHF as they relate to methionine synthase – MS), and MTRR (related to maintaining B12 levels needed by the MTR enzyme). In every case the results showed at least 2 and up to 4 enzymes had genetic variations. These results indicate that the nutritional requirements for folate as 5-MTHF, vitamin B12 as methylcobalamin, vitamin B6, vitamin B2, magnesium and zinc will likely be significantly greater than normal.

Given the above information, it seems essential for good health to take nutritional supplements that provide the important nutrients. Below I will discuss various formulas that I have developed and refined over many years that are useful especially for the Methylation Cycle.

Please note that Health Products Distributors, Inc. (HPDI) is the preferred supplier of nutritional supplements by the BodySync genetic testing company.


When looking at the total needs the body has for nutrients that the body does not produce, including fat soluble vitamins (A, D (some), E, K1 and K2), vitamin C, B vitamins (B1, B2, B3, B5, B6, folate, B12, biotin, choline, and inositol), minerals (Ca, Mg, Zn, Se, Cu, Mn, Cr, Mo, K, boron, and vanadium), and betaine it only seems wise to include as a top priority a Multivitamin that includes all of these in what I term therapeutic amounts (carefully selected after evaluating thousands of research studies carried out over many years.)

In this context, it is important to recognize that every enzymatic reaction in the body requires mineral cofactors in order to carry out its function. A good multivitamin provides many of these required minerals.

Additionally, the multivitamin should contain ingredient forms that research has confirmed to be the most absorbable and usable by the body. These include coenzyme B vitamins, Krebs cycle (citrate, alpha-ketoglutarate, succinate, fumarate, & malate) minerals, and amino acid chelates.

In the context of supporting the Methylation Cycle we are looking for specific forms and amounts of B vitamins that can adequately provide the body’s needs. The means that there should be coenzyme folate as 5-MTHF of at least 400 mcg, coenzyme vitamin B-12 as methylcobalamin of at least 200 mcg, Vitamin B6 (including significant amounts of pyridoxal 5′ phosphate) of at least 40 mg, and Vitamin B2 (including significant amounts of riboflavin 5′ phosphate) of at least 25 mg. In addition, magnesium (100 mg) and zinc (at least 20 mg) should be provided.

Please note that the body’s requirements for magnesium is generally accepted by nutritional experts to be higher than 400 mg daily (and as high as 1,000 mg daily). For this reason we generally recommend that a person take supplemental magnesium (such as HPDI’s MYO-MAG) at levels over 400 mg daily.

The two multivitamin formulas Health Products Distributors provides for adults that meet these requirements (and more) are the Hank & Brian’s Mighty Multi-Vite and Multi Two (in both capsule and tablet forms). Click on the bottles below for technical details.

Hank & Brian's Mighty Multi-Vite multivitamin methylation cycle

Multi Two Caps or Tablets methylation cycle


In situations where significant genetic variations are present it may be wise to add a B COMPLEX supplement to the MULTIVITAMIN to provide even larger amounts of the needed B vitamins. HPDI provides a B-Complex-50 product that includes significant amounts of coenzyme forms and contains 50 mg of Vitamin B1, 50 mg of Vitamin B2, 100 mg of Vitamin B3, 50 mg of Vitamin B6, 500 mcg of coenzyme folate (both folinic acid and 5-MTHF), 100 mcg of B12 (both methylcobalamin and hydroxocobalmin), 50 mg of Vitamin B5 (pantothenic acid), 500 mg of Biotin, 50 mg of choline, and 50 mg of inositol. Click on the bottle below for technical details.

B-Complex-50 full spectrum B vitamins with coenzyme forms methylation cycle


In situations where an inadequate diet is present and genetic testing indicates an MTHFR variation (especially a homozygous variation) Health Products Distributors provides a 5-MTHF folate supplement that easily absorbs into the body and can be directly used in combination with Vitamin B12 to convert homocysteine to methionine. Click on the bottle below for technical details.

5-MTHF 1 mg in veggie cap methylation cycle

5-MTHF 1 mg in veggie cap


It is often the case for older patients and vegetarians that Vitamin B12 is deficient. In these cases it is wise to supplement with a significant amount of methylcobalamin to ensure that the Methylation Cycle has sufficient to effectively convert homocysteine into methionine. Health Products Distributors Vitamin B12 contains 5 mg of methylcobalamin in sublingual lozenge form that supports excellent absorption even if swallowed and absorbed by diffusion. Click on the bottle below for technical details.

Vitamin B-12 5 mg methylcobalamin sublingual lozenge methylation cycle

Vitamin B-12 – 5 mg Methylcobalamin sublingual lozenge.


Magnesium and zinc are two important minerals used in the betaine pathway of the Methylation Cycle in which homocysteine is converted back to methionine.

In the body magnesium is involved in more than 400 essential metabolic reactions and is required by the adenosine triphosphate (ATP)-synthesizing protein in mitochondria. ATP, the molecule that provides energy for almost all metabolic processes, exists primarily as a complex with magnesium (MgATP). Therefore, it also is involved in converting methionine to SAM.

Over 300 different enzymes depend on zinc for their ability to catalyze vital chemical reactions. Zinc-dependent enzymes can be found in all known classes of enzymes.

Health Products Distributors provides 100 mg magnesium/vcap in its MYO-MAG supplement which is especially important in increasing ATP in the Krebs Cycle. This product also contains vitamin B1, vitamin B2, and vitamin B6 with substantial amounts of coenzyme forms and manganese. Click on the bottle below for technical details.

MYO-MAG with 100 mg magnesium per serving key B vitamins methylation cycle

MYO-MAG with 100 mg magnesium per serving and key B vitamins.

Health Products Distributors provides 25 mg zinc/serving in its Double Zinc Plus supplement. This formula provides zinc in the picolinate and citrate forms as well as 3 mg of P5P (coenzyme B6). Click on the bottle below for technical details.

Double Zinc Plus supplement with P5P and 25 mg zinc methylation cycle

Double Zinc Plus supplement with P5P and 25 mg zinc


The Methylation Cycle is recognized as one of the most important metabolic pathways in the human body. When not properly supported by key B vitamins and minerals, the Methylation Cycle can become severely imbalanced which can lead to a very wide range of poor health conditions. Furthermore, genetic variations in the genes that produce important enzymes allowing the Methylation Cycle to function correctly lead to even further imbalances and greater possibility for conditions of poor health.

In this article, I have provided insight into how the Methylation Cycle works and how it can be significantly supported by lifestyle changes regarding diet and environment (Epigenetics) and by specific B vitamins and mineral supplements that I have developed over many years. In addition, we have shown that knowledge gained from genetic testing can further provide a critical understanding of your specific needs so that your health can be optimized.


Homocysteine Genetics – Coenzyme B Vitamins




Dr. Hank Liers, PhD pro-c™ pro-c super antioxidant formulaFred Liers PhD pro-c antioxidant vitamin c nrf2 formulaLooking for an advanced antioxidant formula? Already using or recommending vitamin C? Curious about cellular Nrf2 activation? Look no further than PRO-C™.

PRO-C™ is among the most effective antioxidant formulas available. It is an HPDI foundational supplement that works most effectively when used with multivitamins, essential fats, and superfoods. However, it is also an excellent standalone formula that can rapidly provide the body with extremely high protection from free radicals.

We ourselves have taken PRO-C daily for many years with excellent results. Our personal experience together with detailed feedback from health professionals and end-users affirms the effectiveness of PRO-C as a super-antioxidant–vitamin C-Nrf2 activator formula.

PRO-C provides 500 mg of buffered vitamin C per capsule (buffered with calcium, magnesium, and zinc) along with grape extract (seed, skin, pulp) and green tea extract (95% polyphenols). In addition, we include a special combination of the “network antioxidants” l-glutathione (reduced), n-acetyl-l-cysteine (NAC), r-lipoic acid, and selenium. Vitamin B2 and Vitamin B6 in coenzyme forms support the enzymatic effectiveness of the “network antioxidants”. The formula works so well because this combination of ingredients leverages the antioxidant power of vitamin C, grape extract, green tea extract, and the other nutrients to act synergistically in order to maximize effectiveness.


What you may not know is the history of the development PRO-C and the scientific knowledge on which Dr. Hank Liers based his formulation of it.

Dr. Hank formulated his first product in 1989. It was a potent antioxidant formula he called PYC-C™ (sounds like “pixie”). PYC-C consisted of a combination of buffered Vitamin C (including magnesium, calcium, and zinc ascorbates) and pycnogenols from pine bark.

Much of the scientific research data Dr. Hank collected during the development of PYC-C regarding oligomeric proanthocyanidins (OPC) he later incorporated into an article (currently published on this blog) titled “Review of Scientific Research on Oligomeric Proanthocyanidins (OPC)” (rev. 2017)

By 1997 Dr. Hank had gathered a great deal of new scientific information regarding green tea catechins and the nutrients termed “network antioxidants” by Dr. Lester Packer, director of Packer Lab at University of California, Berkeley. Beyond this information, Dr. Hank studied additional research regarding how various nutrients worked together synergistically. At that point, he was ready to formulate the new, improved PRO-C™ super antioxidant formula.

PRO-C combines the ingredients of PYC-C (now known as OPC-C™) and uses grape pulp, skin, and seed extract with green tea extract (with high polyphenols >95% and EpiGalloCatechinGalate (EGCG) >45%), n-acetyl-l-cysteine (NAC), reduced glutathione (GSH), R-lipoic acid, selenium, and coenzyme Vitamins B2 and B6.

PRO-C super antioxidant formula 180 cap 90 cap

HPDI launched PRO-C™ in late 1997. It rapidly became one of our best-selling products. Our customers raved about how effective it was for them if they felt like they were “coming down with something” (like a cold, flu, virus, infection, etc.). Greater skin elasticity greatly helped pregnant women avoid stretch marks and episiotomies. Today, we highly recommend its use together with our other Foundational Supplements to ensure optimal health and anti-aging effects.


PRO-C™ super antioxidant formula is extremely synergistic, especially in so far as it increases the body’s ability to quench free radicals in its aqueous (i.e., water-based) compartments. Because antioxidants may become free radicals themselves after they have done their job, the body has developed an elaborate system for recovery of oxidized antioxidants.


Dr. Lester Packer was the primary researcher investigating the synergistic character of antioxidants. He made this statement in his interview with Dr. Richard Passwater after publication of Packer’s The Antioxidant Miracle (1999):

[The major theme of] The Antioxidant Miracle is that antioxidants work in a coordinated manner. They interact with one another, and this interaction, which we like to call the antioxidant network, is very important to the overall antioxidant defense that we possess. The key members of the antioxidant network are vitamin E and vitamin C, but there are other participants in this network. These are thiol antioxidants, antioxidants that contain sulfur groups in the body. Glutathione perhaps is the best known of these, but there are other sulfur-containing antioxidants that also are very important.”

Dr. Packer continues:

“This whole antioxidant network works like an orchestra depending on individuals who have, of course, different complements of antioxidants depending upon their nutritional regimens and the individuality of their own body metabolisms. The idea behind having a network of antioxidants is that if one antioxidant happens to be deficient the others can compensate and still keep the antioxidant defense system strong.”

The following diagram shows some of the relationships in the antioxidant network and how they support each other.

Lester Packer antioxidant network diagram Figure 1 – Dr. Packer’s Antioxidant Network

We see, for example, reduced glutathione (GSH) has the ability to reduce oxidized Vitamin C back to its unoxidized state. Vitamin C reduces oxidized Vitamin E back to its unoxidized state, and both reduces glutathione and spares it for other important functions, including detoxification and immune enhancement.

Many polyphenols (e.g., oligomeric proanthocyanidins (OPCs), anthocyanidins and catechins) found in red grape and green tea extracts spare Vitamin C and glutathione in the body, as well as operate as powerful antioxidants, anti-inflammatories, and connective tissue strengtheners.

grapes grape extract antioxidant

Grapes provide antioxidant nutrients such as polyphenols, OPCs, anthocyans, and resveratrol.

R-Lipoic Acid (see abstracts below) operates as an antioxidant both in its oxidized and reduced states, reduces the oxidized forms of both Vitamin E and Vitamin C, and and has been shown to enhance glutathione levels. Because several of these substances are able to protect Vitamin E contained in cell membranes, this combination also has a significant beneficial effect on the fat soluble antioxidant status of the body!

The nutrients in PRO-C have been carefully selected and balanced to provide optimal effects, especially as related to free radical protection, detoxification, immune system enhancement, connective tissue strengthening, and reduction of inflammation. PRO-C therefore provides outstanding nutritional support in a wide variety of conditions of poor health, as well as acts to support and maintain a state of health and well-being.

It the last several years the research results on Nrf2 activators have become well known and products developed that take advantage of these nutrients. For details see our blog article Natural Phytochemical Nrf2 Activators for Chemoprevention. Researchers have been studying specifically how enzyme-activating substances such as OPCs and anthocyans activate a transcription factor known as Nrf2 that causes the body to endogenously produce higher levels of a wide variety of protective enzymes including superoxide dismutase (SOD), catalase, and glutathione peroxidase.

Although we did not know about Nrf2 activators in 1997 when we formulated PRO-C, we have subsequently learned that four of the ingredients in the formula have powerful Nrf2 activity. These include grape seed extract, green tea extract, NAC, and r-lipoic acid. With this knowledge, we now understand that PRO-C provides both powerful external antioxidants (with extremely high ORAC5.0 values) that support redox cycles within the body, but also provides ingredients that allow the body to endogenously produce powerful protective enzymes for even greater free-radical protection and health.


PRO-C contains buffered vitamin C (in the form of powdered calcium, magnesium, and zinc ascorbates), high-potency grape extract (from grape pulp, skins, and seeds), green tea extract (with>95% polyphenols and >45% EGCG), reduced glutathione, N-Acetyl-L-Cysteine (NAC), R-lipoic acid, coenzyme forms of vitamin B2 (R5P) and vitamin B6 (P5P), and selenium.

Below we will discuss each ingredient and show some of the research that confirms its effectiveness.


Vitamin C typically is called l-ascorbic acid or ascorbate and is an essential nutrient for humans and other animal species. The term “vitamin C” refers to a number of vitamins that have vitamin C activity in animals, including ascorbic acid and its salts (e.g., magnesium ascorbate, calcium ascorbate, sodium ascorbate, etc.), and some oxidized forms such as dehydroascorbate and semidehydroascorbate.

Vitamin C is known to perform many critical functions within the body involving detoxification, tissue building, immune enhancement, pain control, and controlling or killing pathogenic organisms. It is also known to be helpful for wound and bone healing, healthy skin and eyes, fighting infections, stress control, toxic exposure, and repairing damaged tissue of all types. For much more information on the many benefits of Vitamin C see our blog article Vitamin C – An Amazing Nutrient.

Below are two abstracts that show some of the beneficial effects of Vitamin C when used with other network antioxidants:

Exhaustive physical exercise causes oxidation of glutathione status in blood: prevention by antioxidant administration.
Sastre J, Asensi M, Gasco E, Pallardo FV, Ferrero JA, Furukawa T, Vina J
In: Am J Physiol (1992 Nov) 263(5 Pt 2):R992-5

We have studied the effect of exhaustive concentric physical exercise on glutathione redox status and the possible relationship between blood glutathione oxidation and blood lactate and pyruvate levels. Levels of oxidized glutathione (GSSG) in blood increase after exhaustive concentric physical exercise in trained humans. GSSG levels were 72% higher immediately after exercise than at rest. They returned to normal values 1 h after exercise. Blood reduced glutathione (GSH) levels did not change significantly after the exercise. We have found a linear relationship between GSSG-to-GSH and lactate-to-pyruvate ratios in human blood before, during, and after exhaustive exercise. In rats, physical exercise also caused an increase in blood GSSG levels that were 200% higher after physical exercise than at rest. GSH levels did not change significantly. Thus, both in rats and humans, exhaustive physical exercise causes a change in glutathione redox status in blood. We have also found that antioxidant administration, i.e., oral vitamin C, N-acetyl-L- cysteine, or glutathione, is effective in preventing oxidation of the blood glutathione pool after physical exercise in rats.

The effect of glutathione and vitamins A, C, and E on acute skin flap survival.

Hayden RE, Paniello RC, Yeung CS, Bello SL, Dawson SM
In: Laryngoscope (1987 Oct) 97(10):1176-9

Vitamins A, C, and E act as antioxidants and as free radical scavengers in biological systems. Glutathione is involved in several reactions in vitamin metabolism and also plays an important role in cell membrane protection against lipid peroxidation by free radicals. We sought to use these natural defense mechanisms against oxygen free radicals formed during reperfusion of ischemic skin flaps. An acute axial random skin flap model was utilized in the rat. Vitamins or glutathione were administered by oral gastric tube or intravenously in the perioperative period, and survival of the flap was measured at 1 week. Glutathione, beta-carotene, ascorbic acid and alpha-D- tocopherol showed mean flap survival of 84% to 89%, each of which was significantly improved over saline controls (67% p less than .0005). The mechanisms and biochemistry of these vitamins, and their interactions with other vitamins and with glutathione, are discussed, along with clinical implications of free radical scavenging and skin flap survival.


Grape extract (seeds, skin, pulp) contain highly bioavailable bioflavonoid complexes that in research studies have been shown to have powerful antioxidant capability. The Oligomeric Proanthocyanidins (OPCs) in grape seed extract are able to strengthen collagen fibers in aging or damaged connective tissue and can act as a preventative against connective tissue degradation.

Some research indicates that anthocyans, which are found in extracts of grape skin and stems (but not in grape seed extract), can reduce oxidized glutathione while at the same time become reduced themselves. In addition, extracts of grape skin and stems (but not those of grape seed extract) contain a material called trans-resveratrol that has been shown to have chemopreventive effects.

Below we have provided some of the abstracts that are included in our broad list of relevant abstracts for PRO-C.

Protective effects of grape seed proanthocyanidins and selected antioxidants against TPA-induced hepatic and brain lipid peroxidation and DNA fragmentation, and peritoneal macrophage activation in mice.
Bagchi D, Garg A, Krohn RL, Bagchi M, Bagchi DJ, Balmoori J, Stohs SJ
In: Gen Pharmacol (1998 May) 30(5):771-6

1. The comparative protective abilities of a grape seed proanthocyanidin extract (GSPE) (25-100 mg/kg), vitamin C (100 mg/kg), vitamin E succinate (VES) (100 mg/kg) and beta-carotene (50 mg/kg) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced lipid peroxidation and DNA fragmentation in the hepatic and brain tissues, as well as production of reactive oxygen species by peritoneal macrophages, were assessed. 2. Treatment of mice with GSPE (100 mg/kg), vitamin C, VES and beta-carotene decreased TPA-induced production of reactive oxygen species, as evidenced by decreases in the chemiluminescence response in peritoneal macrophages by approximately 70%, 18%, 47% and 16%, respectively, and cytochrome c reduction by approximately 65%, 15%, 37% and 19%, respectively, compared with controls. 3. GSPE, vitamin C, VES and beta-carotene decreased TPA-induced DNA fragmentation by approximately 47%, 10%, 30% and 11%, respectively, in the hepatic tissues, and 50%, 14%, 31% and 11%, respectively, in the brain tissues, at the doses that were used. Similar results were observed with respect to lipid peroxidation in hepatic mitochondria and microsomes and in brain homogenates. 4. GSPE exhibited a dose-dependent inhibition of TPA- induced lipid peroxidation and DNA fragmentation in liver and brain, as well as a dose-dependent inhibition of TPA-induced reactive oxygen species production in peritoneal macrophages. 5. GSPE and other antioxidants provided significant protection against TPA-induced oxidative damage, with GSPE providing better protection than did other antioxidants at the doses that were employed.

Clinical and capillaroscopic evaluation of chronic uncomplicated venous insufficiency with procyanidins extracted from vitis vinifera
Costantini A, De Bernardi T, Gotti A
In: Minerva Cardioangiol (1999 Jan-Feb) 47(1-2):39-46

BACKGROUND: The pharmacological treatment of non-complicated chronic venous insufficiency is a current and well-debated topic. The introduction of new products with action on the venous system, improved knowledge on the physiopathology of venous insufficiency and the possibility provided by new analytical instruments, have given new impulse to the consolidation of the clinical value of phlebotonics in this indication. METHODS: In light of this, 24 patients with non-complicated chronic venous insufficiency were treated with oral administration of Oligomeric Proanthocyanidins (Pycnogenols-OPC) 100 mg/day. To evaluate the therapeutic efficacy of the treatment, an instrumental evaluation by optical probe capillaroscope was employed in addition to the traditional subjective clinical parameters: swelling, itching, heaviness and pain. The videocapillaroscope examination was performed at the lower third of the leg and the first toe. Edema in the capillaroscopic field, the number of observable capillaries and the capillary dilatation were the parameter chosen to evaluate the efficacy of treatment. All patients completed the study with no reports of adverse events during the period of observation. RESULTS: The results obtained show a positive clinical response (improved or absent symptoms) in over 80% of patients, with significant improvement of symptoms already evident after the first 10 days of treatment. The mechanism of action of the OPCs explains the rapid reduction of the swelling of the lower limbs and correlated with this are the other evaluable symptoms: heaviness and itching. Particularly striking results were observed for itching and pain which completely disappeared during the course of therapy in 80% and 53% of the patients respectively. Noteworthy is the good correlation between the clinical and instrumental data, with improvement in a total of 70% of patients. CONCLUSIONS: The results obtained in the course of this clinical experience, with evident improvement already during the first weeks of treatment, the absence of adverse events added to the benefit of a once-a-day administration, justify the use of OPC in the treatment of non-complicated chronic venous insufficiency.

Polymeric procyanidin fraction from defatted grape seeds protects HepG2 cells against oxidative stress by inducing phase II enzymes via Nrf2 activation.
Younghwa Kim, Youngmin Choi, Hyeonmi Ham, Heon-Sang Jeong, Junsoo Lee
Kim, Y., Choi, Y., Ham, H. et al. Food Sci Biotechnol (2013) 22: 485. https://doi.org/10.1007/s10068-013-0105-x

Nuclear factor erythroid 2-related factor 2 (Nrf2) is an important transcription factor that regulates antioxidant response element (ARE)-driven phase II detoxification enzymes. In this study, induction of phase II enzymes via Nrf2/ARE activation in the cytoprotective effect of crude polyphenol extract (CPE), oligomeric procyanidin fraction (OPF), and polymeric procyanidin fraction (PPF) from defatted grape seeds in HepG2 cells was evaluated. Among these treatments, the treatment with PPF significantly increased Nrf2 protein expression in the nuclear fraction. Treating the samples increased heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductase 1 (NQO1) protein expression in a dose-dependent manner, and PPF significantly increased the levels of phase II enzymes. Cellular generation of reactive oxygen species (ROS) were effectively reduced by PPF. These results suggest that pretreatment with PPF shows a cytoprotective effect by inhibiting ROS production and inducing HO-1 and NQO1 expression via Nrf2 activation in HepG2 cells.


Green tea extract is obtained from the unfermented leaves of Camellia sinensis for which numerous biological activities have been reported including: antimutagenic, antibacterial, hypocholesterolemic, antioxidant, and protective against tumorigenesis. Below we have selected a few of the many abstracts we have on file showing the benefit of green tea extract.

Green tea antioxidant polyphenols catechins

Green tea leaves are high in antioxidant polyphenols and catechins.

Enhancement of antioxidant and phase II enzymes by oral feeding of green tea polyphenols in drinking water to SKH-1 hairless mice: possible role in cancer chemoprevention.
Khan SG, Katiyar SK, Agarwal R, Mukhtar H
In: Cancer Res (1992 Jul 15) 52(14):4050-2

Following the oral feeding of a polyphenolic fraction isolated from green tea (GTP) in drinking water, an increase in the activities of antioxidant and phase II enzymes in skin, small bowel, liver, and lung of female SKH-1 hairless mice was observed. GTP feeding (0.2%, w/v) to mice for 30 days significantly increased the activities of glutathione peroxidase, catalase, and quinone reductase in small bowel, liver, and lungs, and glutathione S-transferase in small bowel and liver. GTP feeding to mice also resulted in considerable enhancement of glutathione reductase activity in liver. In general, the increase in antioxidant and phase II enzyme activities was more pronounced in lung and small bowel as compared to liver and skin. The significance of these results can be implicated in relation to the cancer chemopreventive effects of GTP against the induction of tumors in various target organs.

In: Anticancer Drugs (1996 Jun) 7(4):461-8
Institutional address: Department of Pharmacology and Toxicology College of Pharmacy University of Arizona Tucson 85721 USA.

Green tea is an aqueous infusion of dried unfermented leaves of Camellia sinensis (family Theaceae) from which numerous biological activities have been reported including antimutagenic, antibacterial, hypocholesterolemic, antioxidant, antitumor and cancer preventive activities. From the aqueous-alcoholic extract of green tea leaves, six compounds (+)-gallocatechin (GC), (-)-epicatechin (EC), (-)- epigallocatechin (EGC), (-)-epicatechin gallate (ECG), (-)- epigallocatechin gallate (EGCG) and caffeine, were isolated and purified. Together with (+)-catechin, these compounds were tested against each of four human tumor cells lines (MCF-7 breast carcinoma, HT-29 colon carcinoma, A-427 lung carcinoma and UACC-375 melanoma). The three most potent green tea components against all four tumor cell lines were EGCG, GC and EGC. EGCG was the most potent of the seven green tea components against three out of the four cell lines (i.e. MCF-7 breast cancer, HT-29 colon cancer and UACC-375 melanoma). On the basis of these extensive in vitro studies, it would be of considerable interest to evaluate all three of these components in comparative preclinical in vivo animal tumor model systems before final decisions are made concerning which of these potential chemopreventive drugs should be taken into broad clinical trials.


Glutathione and NAC (a major precursor of glutathione) both provide important protection against toxins and free radicals, and can strengthen the immune system. Glutathione is considered to be one of the most important protective substances in the human body with almost 60% of liver detoxification accounted for by this key substance. In addition, glutathione is one of the most potent anti-viral substances known.

Some research has indicated that glutathione may not be able to enter easily into certain types of cells, but NAC is able to enter these cells and be converted into glutathione once inside the cell. Thus, the combination of glutathione and NAC appear to be more potent than either alone.

Below we provide some of the key abstracts we have on file regarding NAC and glutathione.

GSH rescue by N-acetylcysteine.
Ruffmann R Wendel A
In: Klin Wochenschr (1991 Nov 15) 69(18):857-62

Reduced glutathione (GSH) is the main intracellular low molecular weight thiol. GSH acts as a nucleophilic scavenger and as an enzyme-catalyzed antioxidant in the event of electrophilic/oxidative tissue injury. Therefore, GSH has a major role as a protector of biological structures and functions. GSH depletion has been recognized as a hazardous condition during paracetamol intoxication. Conversely, GSH rescue, meaning recovery of the protective potential of GSH by early administration of N-acetylcysteine (NAC), has been found to be life-saving. Lack of GSH and electrophilic/oxidative injury have been identified among the causes of the adult respiratory distress syndrome (ARDS), idiopathic pulmonary fibrosis (IPF), and the acquired immunodeficiency syndrome (AIDS). Experimental and early clinical data (in ARDS) point to the role of NAC in the treatment of these conditions. Recently, orally given NAC has been shown to enhance the levels of GSH in the liver, in plasma, and notably in the bronchoalveolar lavage fluid. Rescue of GSH through NAC needs to be appreciated as an independent treatment modality for an array of different disease, all of which have one feature in common: pathogenetically relevant loss of GSH.

Cysteine and glutathione concentrations in plasma and bronchoalveolar lavage fluid after treatment with N-acetylcysteine.
Bridgeman MM Marsden M MacNee W Flenley DC Ryle AP
In: Thorax (1991 Jan) 46(1):39-42

N-acetylcysteine (600 mg/day) was given to patients by mouth for five days before bronchoscopy and bronchoalveolar lavage to determine whether N-acetylcysteine could increase the concentrations of the antioxidant reduced glutathione in plasma and bronchoalveolar lavage fluid. Bronchoalveolar lavage was performed 1-3 hours (group 2, n = 9) and 16-20 hours (group 3, n = 10) after the last dose of N-acetylcysteine and the values were compared with those in a control group receiving no N-acetylcysteine (group 1, n = 8). N-Acetylcysteine was not detected in plasma or lavage fluid. Plasma concentrations of cysteine, the main metabolite of N-acetylcysteine and a precursor of reduced glutathione, were greater in the groups receiving treatment (groups 2 and 3) than in group 1. Cysteine concentrations in lavage fluid were similar in the three groups. Concentrations of reduced glutathione were greater in both plasma and lavage fluid in group 2 than in group 1. These data suggest that N-acetylcysteine given by mouth is rapidly deacetylated to cysteine, with resulting increases in the concentrations of cysteine in plasma and of reduced glutathione in plasma and the airways, which thus temporarily increase the antioxidant capacity of the lung.


R-Lipoic Acid is normally made at low levels in the human body, where it functions primarily as an important metabolic nutrient in the conversion of pyruvic acid into acetyl coenzyme A. As such, it plays a crucial role in the metabolism of both fats and carbohydrates into energy. In addition, r-lipoic acid functions as an extremely powerful antioxidant capable of trapping many different types of free radicals in the body.

Because it is both water and fat soluble, lipoic acid is able to operate in a broader range of body tissues than most other antioxidants. Its small size allows lipoic acid to enter areas of the body not easily accessible to many other substances; this allows lipoic acid, for example, to enter the cell nucleus and prevent free-radical damage to DNA.

Because it is such a powerful antioxidant and can easily function as such in both a reduced and oxidized state, lipoic acid is able to protect other important antioxidants such as glutathione, Vitamin E, and Vitamin C. R-lipoic acid is also able to chelate heavy metals such as lead, cadmium, mercury, free iron, and free copper out of the body.

Below we provide relevant scientific abstracts from our database regarding R-Lipoic acid.

Alpha-Lipoic acid as a biological antioxidant.
Packer L Witt EH Tritschler HJ
In: Free Radic Biol Med (1995 Aug) 19(2):227-50

alpha-Lipoic acid, which plays an essential role in mitochondrial dehydrogenase reactions, has recently gained considerable attention as an antioxidant. Lipoate, or its reduced form, dihydrolipoate, reacts with reactive oxygen species such as superoxide radicals, hydroxyl radicals, hypochlorous acid, peroxyl radicals, and singlet oxygen. It also protects membranes by interacting with vitamin C and glutathione, which may in turn recycle vitamin E. In addition to its antioxidant activities, dihydrolipoate may exert prooxidant actions through reduction of iron. alpha-Lipoic acid administration has been shown to be beneficial in a number of oxidative stress models such as ischemia-reperfusion injury, diabetes (both alpha-lipoic acid and dihydrolipoic acid exhibit hydrophobic binding to proteins such as albumin, which can prevent glycation reactions), cataract formation, HIV activation, neurodegeneration, and radiation injury. Furthermore, lipoate can function as a redox regulator of proteins such as myoglobin, prolactin, thioredoxin and NF-kappa B transcription factor. We review the properties of lipoate in terms of (1) reactions with reactive oxygen species; (2) interactions with other antioxidants; (3) beneficial effects in oxidative stress models or clinical conditions.

Regeneration of glutathione by α-lipoic acid via Nrf2/ARE signaling pathway alleviates cadmium-induced HepG2 cell toxicity.
Zhang J, Zhou X, Wu W, Wang J, Xie H, Wu Z.
In: Environ Toxicol Pharmacol. 2017 Apr;51:30-37. doi: 10.1016/j.etap.2017.02.022. Epub 2017 Feb 27.

Alpha-lipoic acid (α-LA) is an important antioxidant that is capable of regenerating other antioxidants, such as glutathione (GSH). However, the underlying molecular mechanism by which α-LA regenerates GSH remains poorly understood. The current study aimed to investigate whether α-LA regenerates GSH by activation of Nrf2 to alleviate cadmium-induced cytotoxicity in HepG2 cells. In the present study, we found that cadmium induced cell death by depletion of GSH through inactivation of Nrf2. Addition of α-LA to cadmium-treated cells reactivated Nrf2 and regenerated GSH through elevating the Nrf2-downstream genes γ-glutamate-cysteine ligase (γ-GCL) and GR, both of which are key enzymes for GSH synthesis. However, blocking Nrf2 with brusatol in the cells co-treated with α-LA and cadmium reduced the mRNA and the protein levels of γ-GCL and GR, thus suppressed GSH regeneration by α-LA. Our results indicated that α-LA activated Nrf2 signaling pathway, which upregulated the transcription of the enzymes for GSH synthesis and therefore GSH contents to alleviate cadmium-induced cytotoxicity in HepG2 cells.


Selenium has been shown by clinical research to be a key mineral in the body’s defenses against free radicals and has been shown to be a major factor in reducing the symptoms of HIV infections and in the prevention of tumors. Selenium is used in conjunction with glutathione to form the powerful enzyme glutathione peroxidase that is responsible for detoxification of peroxides formed during the process of aerobic metabolism in humans and other animals.

Serum selenium concentrations in rheumatoid arthritis.
In: Ann Rheum Dis (1991 Jun) 50(6):376-8

O’Dell JR, Lemley-Gillespie S, Palmer WR, Weaver AL, Moore GF, Klassen LW

Selenium is a trace element and an essential part of the enzyme glutathione peroxidase, which protects cells from oxidative damage. Selenium has been shown to have antiproliferative, anti-inflammatory, antiviral, and immune altering effects. Serum selenium concentrations in 101 patients with seropositive rheumatoid arthritis were found to be significantly lower than those in 29 normal, healthy controls (mean (SD) 148 (42) v 160 (25) micrograms/l) and also lower than those in eight patients with fibrositis (148 (42) v 166 (25) micrograms/l). It is speculated that serum selenium concentrations may modulate the effect of viral or other infections in subjects with the appropriate genetic background and in this way enhance the development or progression of rheumatoid arthritis.

Studies on selenium in top athletes.
Dragan I, Ploesteanu E, Cristea E, Mohora M, Dinu V, Troescu VS
In: Physiologie (1988 Oct-Dec) 25(4):187-90

The authors performed a controlled trial in 18 top athletes (9 weight lifters and 9 rowers, girls) in order to make evident some chronic and acute effects (antioxidant) of selenium. Nonprotein–SH (essential glutathione), lipid peroxides (MDA-malondialdehyde), glucose-6-phosphate dehydrogenases (G-6-PDH) and fructose-1,6- diphosphate aldolase in serum, have been recorded initially on basal conditions, after 3 weeks of treatment (100 micrograms/day selenium or placebo) and again after 3 weeks of treatment, also on basal conditions, when crossing over the groups (between a free interval of 10 days). In another trial we registered these parameters on basal conditions and after two hours of hard training accompanied by a per oral administration of 150 micrograms selenium (respectively placebo). The results show significant changes under selenium treatment of the peroxides, G-6-PDH and light changes, not significant of the nonprotein–SH, changes which could suggest an antioxidant effect of this element.


Vitamin B2 as coenzyme riboflavin-5-phosphate is a key vitamin that supports the regeneration of glutathione (via glutathione reductase). Vitamin B6 as coenzyme pyridoxal-5-phosphate is a key vitamin that supports the ability of glutathione to combine with toxic substances (via glutathione transferase) in the process of eliminating them from the body. They are especially effective in their coenzyme forms which allows them to be directly utilized by the body starting in the intestinal tract.


Magnesium, zinc, and calcium synergistically work with (and enhance the effects of) the other ingredients in PRO-C. Minerals are especially needed as active components of enzymes that drive metabolic activity. For example, magnesium is required in the functioning of more than 325 types of enzymes.


HIGHLY EFFECTIVE VITAMIN C FORMULA PLUS ANTIOXIDANTS. A complete vitamin C formula, a powerful antioxidant Formula, and Nrf2 activator combined in a single advanced supplement!

POWERFUL, SYNERGISTIC FREE-RADICAL QUENCHING FORMULA. PRO-C™ components work together to quench free radicals in your body. Vitamin C enables grape seed extract to function more effectively, and conversely grape seed extract potentiates vitamin C. Green tea extract boosts ORAC (Oxygen Radical Absorbance Capacity) value.

PROVIDES SIGNIFICANT AMOUNTS OF POWERFUL NRF2 ACTIVATORS (from Grape Extract, Green Tea Extract, NAC, and R-Lipoic Acid) that stimulate the production of the body’s own protective antioxidants including superoxide dismutase, catalase, glutathione peroxidase, and heme oxygenase.

SUPERIOR, BUFFERED (NON-ACIDIC) FORM OF VITAMIN C. Mineral Ascorbates never acidify your body, keeping you pH balanced. Staying alkaline is an important element in maintaining a healthy body.

RAPID ASSIMILATION. Capsule form ensures rapid uptake and assimilation in the body. You may also empty capsule contents into water, food, or directly Into mouth, if desired. Good, mildly tart taste!


One (1) vegetarian capsule of PRO-C provides the following percentages of the Daily Value:

Vitamin C (from mineral ascorbates) 500 mg 833%
BioVin® Grape Extract 30 mg *
Green Tea Extract 30 mg *
Calcium (from calcium ascorbate) 23 mg 2.3%
Magnesium (from magnesium ascorbate) 23 mg 5.7%
L-Glutathione (reduced) 20 mg *
N-Acetyl-L-Cysteine (NAC) 15 mg *
R-Lipoic Acid 5 mg *
Zinc (from zinc ascorbate) 2 mg 13%
Vitamin B2 (from riboflavin-5′-phosphate) 1 mg 118%
Vitamin B6 (from pyridoxal-5′-phosphate) 1 mg 50%
Selenium (from l-selenomethionine) 10 mcg *

* No established Daily Value

DIRECTIONS: As a dietary supplement take 1–3 capsules or more daily in divided doses (i.e., spread out over the day), or as recommended by a health care professional. It initially may be useful to take up to 6 capsules per day in divided doses for one week. The contents of the capsule may be emptied into juice or food, as needed.

INGREDIENTS: PRO-C™ SUPER ANTIOXIDANT FORMULA contains only the highest-quality USP grade magnesium ascorbate, USP grade calcium ascorbate, BioVin® grape extract (greater than 75% polyphenols, 93% OPC, greater than 3.5% anthocyanidins from grape pulp, skins, and seeds, and a small amount of trans resveratrol), green tea extract (95% min. polyphenols and 45% min. EGCG), l-glutathione (reduced), USP grade n-acetyl-l-cysteine, USP grade zinc ascorbate, r-(+)-lipoic acid, riboflavin-5′-phosphate, pyridoxal-5′-phosphate, l-selenomethionine, the smallest amounts of microcrystalline cellulose and silica in a vegetarian capsule.

PRO-C™ does not contain wheat, rye, oats, corn antigen, barley, gluten, soy, egg, dairy, yeast, sugar, sulfates, phosphates (other than coenzyme forms), fats, chlorides, GMOs, wax, preservatives, colorings, or artificial flavorings.

Click here to order PRO-C™.



The Antioxidant Miracle. Lester Packer, PhD, and Carol Coleman. New York: John Wiley and Sons, 1999.

How to Live Longer and Feel Better. Dr. Linus Pauling. Corvallis, OR: Oregon State University Press, 2006.


Review of Scientific Research on Oligomeric Proanthocyanidins (OPC)” (rev. 2017) by Hank Liers, PhD

“Vitamin C – An Amazing Nutrient” by Hank Liers, PhD

PRO-C™ and Ultimate Protector™ – Comparison by Hank Liers, PhD

“Antioxidant Cocktail Update: Part 1: The Take Home Message is to Use Antioxidant Supplements”
(An interview of Dr. Lester Packer by Richard A. Passwater, PhD, Whole Foods Magazine 1999)


PRO-C™ / Vitamin C Abstracts

Catechin Abstracts

N-Acetyl-L-Cysteine (NAC) Abstracts

Lipoic Acid Abstracts


(Therapeutic Nutrition Based Upon Biochemical Individuality)


PRO-C™Super Antioxidant Formula

Ultimate Protector™Nrf2 Activator Formula


HPDI Vitamin C Products


Dr. Hank Liers, PhD homocysteine coenzyme B vitaminsWe previously published an article titled FOLATE INGREDIENTS – FOLINIC ACID & 5-MTHF in which we discuss how coenzyme folate vitamins are far superior to the synthetic folic acid form. In today’s article, I take a more in-depth look at how homocysteine is formed from methionine, how genetics affects the metabolic pathways, and how B vitamins are used in metabolic pathways.

One way to look at the metabolic pathways of methionine (an essential amino acid) is that it provides a way for the body to convert this sulfur containing amino acid either to cysteine and its key by-products glutathione, taurine, and sulfates or allows remethylation back to methionine to occur using either the Folate Cycle or the Trimethyl glycine (betaine) pathways.

Figure 1 shows these metabolic pathways including the vitamins required at each step including vitamin B6 (as P-5-P), methylcobalamin, and 5-methyltetrahydrofolate (5-MTHF). In addition, it shows the key enzymes produced by the body at each step. These enzymes include CBS (cystathione beta synthase), BHMT (betaine homocysteine methyltransferase), MS (methionine synthase), and MTHFR (methylene tetrahydrofolate reductase).

homocysteine metabolism diagram

Figure 1. Metabolic Pathways in Methionine and Homocysteine Metabolism


It is highly important that the various metabolic pathways function correctly to keep homocysteine at healthy levels (6–8 µmol/L). Unfortunately, high levels of homocysteine in the body (10–20 µmol/L) are a factor in a wide range of health issues, including:

  • Greater risk for heart problems, including coronary artery disease, heart attacks, stroke, high blood pressure, congestive heart failure, and abnormal cholesterol levels. This is due to increased inflammation, sometimes due to blood clotting spontaneously, and because of blockages of the major arteries.
  • Mental abnormalities such as depression, anxiety, bipolar disorder, and other mental problems are more common among people with high homocysteine
  • Migraines and headaches in a significant percentage of the population
  • In those who suffer from high homocysteine due to having nutritional deficiencies anemia, aches and pains, hearing loss, age-related macular degeneration (ARMD), slowed development, and birth defects might also be possible
  • Greater risk for dementia, Alzheimer’s disease, brain atrophy, and other cognitive problems
  • In children, skeletal and developmental abnormalities including having a curved spine or protruding chest and rib cage. Some patients appear very tall and thin, and some might also have very long, thin “spider-like” toes and fingers.
  • Behavioral problems, including ADHD, autism and other learning disabilities


Ten or more years ago, questions of how genetics enters into homocysteine metabolism were unlikely to be asked. However, in recent years DNA testing has advanced and is now available to everyone (for example, see my article about Bodysync’s genetic test, DISCOVERING NUTRITIONAL NEEDS THROUGH ADVANCED GENETIC TESTING.

You may have heard a great deal about MTHFR (methylene tetrahydrofolate reductase). This gene is involved in folate metabolism and has a central role in methylation processes like repair of and building new DNA in dividing cells.

In the remethylation pathway for conversion of homocysteine to methionine, MTHFR plays a key role in converting folate into 5-MTHF which is needed along with B12 as methylcobalamin in order for the conversion to take place. Genetic variations in MTHFR have been studied in depth. Of the many variations studies the most significant ones appear to be variations of C677C such as C677T (referred to as heterozygous) or T677T (referred to as homozygous). The heterozygous variant appears in about 30–50% of the population and causes somewhat less efficiency in the conversion of folic acid to 5-MTHF. However, the homozygous variation occurs in about 10% of the population and can have serious effects due to converting little homocysteine back to methionine.

Another variation in MTHFR is called A1298A. These variations are A1298C and C1298C and will have similar effects to the C677C variations. It was interesting to me when I recently analyzed my Bodysync genetic test results showing I carry the variation A1298C (heterozygous), which indicates I may not be effectively converting homocysteine back to methionine.

Additionally, my Bodysync genetic test results also indicate that I have heterozygous variations in the CBS enzyme shown in Figure 1, as well as heterozygous variations in MTR and MTRR enzymes, which are involved with B12 levels in the remethylation pathway. These results indicate that I need to take higher levels of methylcobalamin and 5-MTHF.


Many of the B vitamins on the market today unfortunately are in synthetic form. The body can only use the natural coenzyme forms effectively. For example, the body needs vitamin B6 in the form of P-5-P (pyridoxal-5-phosphate), folate in the form of L-5-MTHF, and B12 in the form of methylcobalamin for proper metabolism of methionine. In some cases the body can use the synthetic forms of pyridoxine HCl, folic acid, and cyanocobalamin but pays a cost (e.g., in time and energy) by having to convert synthetic forms to coenzyme forms.

Add to the prevalence of synthetic B vitamins, the fact that genetic deficiencies are more common than previously assumed, and it becomes clear that the coenzyme forms of B vitamins in the proper amounts are extremely important.

Fortunately, I have always believed it best to include as many coenzyme forms as possible in the nutritional supplements I formulate (over the past 27 years). For example, all HPDI multivitamins include coenzymes of B1, B2, B6, B12, and folate (as 5-MTHF and folinic acid). This is uncommon in most multivitamin formulas on the market. For this reason our supplements are ideally suited to the prevention or resolution of most genetic problems regarding homocysteine.

In addition, I have always chosen to include higher amounts than most multivitamins on the market. We also make available 5-MTHF one milligram (1 mg) capsules and methylcobalamin five milligram (5 mg) sublingual tablets. When genetic variations are in play as discussed above, then providing relatively higher amounts of coenzyme B vitamins that support important requirements in the body seems necessary.

Interestingly, several other nutrients are involved in the pathways involving methionine and homocysteine. These include zinc, magnesium, and Vitamin B2. Our multivitamin formulas and magnesium formulas, especially Myo-Mag with its coenzyme B1, B2, and B6, are recommended to support these nutrient needs. Finally, it has been found that N-Acetyl-L-Cysteine (NAC) can significantly lower homocysteine (by up to 50%), most likely because its gives the body an excellent source of cysteine without have to use methionine.


In this article, I have shown the value of the use of genetic testing and high-quality coenzyme B vitamins in resolving health issues associated with high values of homocysteine in the body.





The Homocysteine Revolution by Kilmer S. McCully, MD

Role of hyperhomocysteinemia in endothelial dysfunction and atherothrombotic disease
(Cell Death and Differentiation 11, S56–S64)


(coenzyme folate)

(vitamin B12)


HPDI Multivitamins



Dr. Hank Liers, PhD 5-MTHF and Folinic Acid folate coenzymeFred Liers PhD 5-MTHF and Folinic Acid folate coenzyme

It is important to know that our scientific knowledge of the B vitamin folate has undergone significant changes in the last 10 years based upon some amazing research studies.

We have come to understand that the biologically active and naturally ocurring folate forms of L-5-methyltetrahydofolate (5-MTHF) and 5-formyltetrahydrofolate (folinic acid) are significantly more effective than folic acid, which is a synthetic oxidized form of folate.

For many years (at least since the 1940s), the only form of folate used in supplements and fortified foods was folic acid. However, a significant body of research has shown that supplemental folic acid may actually accelerate cognitive decline in some older individuals. Folic acid also is being linked to increased risk of colon and rectal cancers, increased risk of childhood asthma born to folic-acid supplemented mothers, and accelerated growth of pre-existing tumors.

Many studies have indicated that a large portion of the population (about 50%) have genetic deficiencies in the enzymes (such as MTHFR) that do not allow the body to properly metabolize folic acid into coenzyme forms needed for proper body function.

Unfortunately, journalists and even many medical professionals haven’t understood that folic acid is not the same as the naturally occurring vitamin folate. Even today, much of the medical mainstream use the terms “folic acid” and “folate” interchangeably. Yet, folic acid is not the same as folate!

The good news is that the folate coenzymes of 5-MTHF and Folinic Acid are now readily available for use in nutritional supplements and are being incorporated into products by knowledgeable companies.


Folate is a water-soluble B vitamin that is naturally present in foods. Folates are  commonly consumed through a diet of green leafy vegetables, sprouts, fruits, brewer’s yeast, animal products such as milk and dairy products, egg yolk, and liver. Formerly known as “folacin,” folate is the generic term for both naturally occurring food folate and folic acid.

spinach folate

Spinach and other green leafy vegetables provide naturally occurring folate.

When consumed, food folates are often hydrolyzed to the monoglutamate form in the gut prior to absorption by active transport across the intestinal mucosa. Passive diffusion also occurs when pharmacological doses of folic acid are consumed.

Before entering the bloodstream, the monoglutamate form is reduced to tetrahydrofolate (THF) and converted to either methyl or formyl forms. However, both of the metabolically active (coenzyme) forms 5-methyl tetrahydrofolate (5-MTHF) and 5-formyl tetrahydrofolate (also known as folinic acid) are found in foods and can enter the cells with no further modification.

Unfortunately folates contained in foods are unstable and susceptible to oxidation; they rapidly lose activity during food processing, manufacturing and storage and have a bioavailability range of 25–50%, depending on the kind of food. Fresh leafy vegetables stored at room temperature may lose up to 70% of their folate activity within three days and a cooking process in water can increase the loss to 95%.

Humans cannot synthesize folate and because of its water soluble nature, the body stores folate to a limited extent. For this reason folate represents a dietary requirement and must be consumed by diet.


Folate deficiency represents one of the most common nutritional deficiencies and may occur when dietary intake is inadequate, when an increased need is not matched by an increased intake (particular physiological conditions such as pregnancy, lactation, child growth), when there is altered absorption/excretion (or losses) and when metabolism or drug use interferes with the ability of the body to use folate.

Several conditions can lead to nutritional folate deficiency. These not only include enzyme defects, malabsorption, digestive system pathology, and liver disease, but also conditions with a high rate of cell turnover such as rapid tissue growth (infants, kids and adolescents), and pregnancy and lactation.

In severe cases deficiency can cause many clinical abnormalities, including macrocytic anemia, cardiovascular diseases, birth neural tube defects (NTDs) and carcinogenesis. Folate deficiency is associated with elevated levels of homocysteine, cerebrovascular and neurological diseases, and mood disorders.


Folate coenzymes are responsible for the following metabolic functions and benefits:

1) Formation of purines and pyrimidines, which in turn are needed for synthesis of the nucleic acids DNA and RNA. This is especially important during fetal development in the first trimester in preventing birth defects, such as neural tube defects.

2) Formation of heme, the iron-containing protein in hemoglobin

3) Interconversion of the 3-carbon amino acid serine from the 2-carbon amino acid glycine

4) Formation of the amino acids tyrosine from phenylalanine and glutamic acid from histidine

5) Formation of the amino acid methionine from homocysteine (Vitamin B12 as methylcobalamin also is needed for this conversion). Elevated levels of homocysteine have been implicated in a wide range of health disorders including atherosclerosis, osteoporosis, Alzheimer’s disease, and depression. In the reconversion of homocysteine to methionine the body uses the methionine to make the important amino acid s-adenosylmethionine (SAMe) which is known to be helpful in cases of depression.

6) Synthesis of choline from ethanolamine

7) Formation and maturation of red and white blood cells

8) Conversion of nicotinamide to N’-methylnicotinamide

Numerous drugs are known to inhibit the body’s ability to utilize folate, including: 1) aspirin, 2) cholesterol lowering drugs, 3) oral birth control pills, 4) antacids, and 5) methotrexate when used for rheumatoid arthritis. When taking these drugs (and many others) it is recommended that you take at least 800 mcg daily of folate, preferably as 5-MTHF and folinic acid.

When taking folate it is recommended that you take adequate amounts of Vitamin B12 as methylcobalamin.


The figure (1.1) shown below provides an overview of how the three forms of folate we will be discussing are metabolized in the cell. Basically the diagram shows that there are two major uses of folate in the body 1) Those dealing with methylation reactions and 2) those dealing with nucleotide biosynthesis, e.g., the production of DNA and RNA.

On the bottom left the diagram shows that 5-MTHF can directly enter the cell and be used for methylation reactions such as the conversion of homocysteine into methionine. On the bottom right the diagram shows that 5-formyl tetrahydrofolate (folinic acid) can directly enter the cell and be used for nucleotide biosynthesis after a few enzymatic conversions.

The top of the diagram shows that folic acid can enter the cell, but must go through a series of enzymatic conversions in order to accomplish what 5-MTHF and folinic acid can accomplish. The box in the lower middle of the diagram indicates where the MTHFR enzyme (see the line with the #5) deficiency can block the metabolism of folic acid.

The diagram shows that all of the important reactions can be accomplished by either 5-MTHF or folinic acid as they can be converted to one another by a series of enzymatic reactions. An important study (see abstract below) has indicated that at least in some cases the presence of a MTHFR enzyme deficiency does not impede the conversion of folinic acid into 5-MTHF.

Folate Metabolism 5-MTHF and Folinic Acid

1.1. Diagram of Folate Metabolism from Vitamin Analysis for the Health & Food Sciences by Ronald R. Eitenmiller and W.O. Lander, Jr.

FOLIC ACID: Once isolated and exposed to air natural folates in food becomes unstable and breaks down, and are generally no longer useful in nutrition. But a small amount of natural folate can be transformed by oxidation (a natural process) into folic acid, a much more stable form with a very long shelf life.

While human and animal cells cannot use the folic acid molecule itself in their normal metabolic processes, human cells (principally the liver) can transform folic acid back into many of its metabolically useful folate forms. That is why folic acid—despite not being found in food—can do so much nutritional good. The best-known example is the prevention of birth defects including spina bifida, cleft lip, and cleft palate.

As we age, however, our bodies become increasingly slower at transforming folic acid into usefully metabolized folates. That’s probably the reason scientists are finding that folic acid (not folate) is associated with cognitive decline in the elderly. Some of these studies have shown significantly elevated levels of unmetabolized (and therefore not useful) folic acid building up in the bloodstreams of supplemented older individuals.

In addition to worsening folic acid metabolism with age, there are also a significant number (as high as 45 percent or more in some populations) of survivable human genetic defects of folate metabolism (MTHFR deficiency) which make it more difficult or, in some circumstances, impossible for sufferers to make metabolic use of folic acid.

We believe it is time to make folic acid supplements a part of history, and use only forms of naturally occurring folate when we use supplements. Although my company produces a liquid folic acid supplement that has been especially useful for some pregnant women who are experiencing gum problems, we have been incorporating the coenzyme form Folinic Acid into supplements for over 10 years, and recently introduced the metabolically active form L-5-MTHF.

A small amount of folic acid (100–200 micrograms, the amount found in many multiple vitamins at present) is not likely to be a major problem for most people. However, more taken daily for years just might raise your long-term risk of colorectal cancer, cognitive decline, or other symptoms of elevated levels of homocysteine. If higher amounts are unavoidable (for example, until all prenatal vitamins switch from folic acid to folate), taking additional folate as 5-MTHF and Folinic Acid will very likely offset the folic acid still found in the multiple. In this regard, I have over the last five years eliminated folic acid from all of the multivitamins and B-Complex vitamins that we now make available.

FOLINIC ACID: Also known as 5-formyl tetrahydrofolate, it is one active form in a group of vitamins known as folates. In contrast to folic acid, a synthetic form of folate, folinic acid is one of the forms of folate found naturally in foods. In the body folinic acid may be converted into any of the other active forms of folate.

Compared to folic acid, folinic acid is expensive costing about 100 times more. However, the fact that the body only requires small amounts (less than one mg) means that one can obtain a two month supply of folinic acid for less than $10.

Folinic acid has been available as a supplement for more than 10 years and as such has been the form most used as a replacement for folic acid.

5-MTHF: Also known as L-5-methyl tetrahydrofolate, it has been difficult to obtain until recently. An Italian company has made a patented form available (Quatrefolic®) that is combined with a vegetarian glucosamine. This form is particularly stable and highly bioavailable.

5-MTHF costs about 400 times more than folic acid. However, because the body requires less than one milligram (1 mg) on a daily basis, a person can buy a two-month supply for about $20.

5-MTHF is now readily available on the market, thereby making it possible to purchase at reasonable prices both coenzyme forms of folate.


As we noted, the importance of natural coenzyme forms of folate is highlighted by the large number of people who cannot convert folic acid to folate usable in the body because they lack the enzymes necessary to make this conversion due to genetics, aging, or faulty metabolism.

For the nearly half of all persons (in some populations) having the functional variation (i.e., mutation) on the MTHFR gene resulting in MTHFR deficiency makes them unable to convert folic acid to a folate form like 5-MTHF that usable by cells. This not only means that their bodies have problems processing B-group vitamins, but also can mean they suffer significant deficiencies (as well as elevated blood folate).

Folate deficiencies can lead to anxiety and panic attacks. Moreover, they can lead to other mood issues, miscarriages, as well as vascular conditions. Recall that elevated levels of homocysteine are associated with folate deficiency.

Another area of interest is research indicating that up to 20% of individuals who carry the MTHFR gene experience migraine headaches.

The effectiveness of natural folates for migraine headaches in persons with MTHFR deficiency is becoming more widely known. Here is a TEDx talk by Prof. Lyn Griffiths from the Griffith Health Institute in Australia showing her work with MTHFR deficiency and migraine (https://www.youtube.com/watch?v=BOgbmF0jYd4). This aspect of her work is highlighted near the end of her talk.

The use of natural folates to help individuals suffering from migraine headache is an area holding great promise.


Folic acid is not the same as folate. Folic acid can present problems in persons lacking the enzymes necessary to convert it into usable forms. Folic acid can also build up in the body in potentially toxic ways.

Supplementing with naturally occurring coenzyme folates, such as 5-MTHF and folinic acid makes sense given advances in our understanding of how the body utilizes dietary folates.

HPDI incorporates natural folate forms into all of its multivitamins and folate products.



Conversion of 5-formyltetrahydrofolic acid to 5-methyltetrahydrofolic acid is unimpaired in folate-adequate persons homozygous for the C677T mutation in the methylenetetrahydrofolate reductase gene.

From: http://www.ncbi.nlm.nih.gov/pubmed/10958818


Methylenetetrahydrofolate reductase (MTHFR) catalyzes the synthesis of 5-methyltetrahydrofolic acid (5-CH(3)-H(4) folic acid), the methyl donor for the formation of methionine from homocysteine. A common C677T transition in the MTHFR gene results in a variant with a lower specific activity and a greater sensitivity to heat than the normal enzyme, as measured in vitro. This study was undertaken to determine the capacity of homozygotes for the MTHFR C677T transition to convert 5-formyltetrahydrofolic acid (5-HCO-H(4) folic acid) to 5-CH(3)-H(4) folic acid, a process that requires the action of MTHFR. Six subjects homozygous for the C677T transition (T/T) and 6 subjects with wild-type MTHFR (C/C) were given a 5-mg oral dose of (6R:,S:)-5-HCO-H(4) folic acid. Plasma and urine were analyzed for 5-CH(3)-H(4) folic acid concentrations using affinity/HPLC coupled with fluorescence or UV detection. The mean areas under the curves created by the rise and fall of plasma 5-CH(3)-H(4) folic acid after the oral dose did not differ between the two genotypes, 424.5 +/- 140.3 (T/T) vs. 424.1+/- 202.4 h.nmol/L (C/C). There also was no significant difference in the mean cumulative 7-h urinary excretion of 5-CH(3)-H(4) folic acid between the T/T (2.5 +/- 1.4 micromol) and C/C (1.9 +/- 1.0 micromol) genotypes. Under the conditions employed, the conversion of oral 5-HCO-H(4) folic acid to 5-CH(3)-H(4) folic acid is not impaired in persons with the T/T MTHFR genotype. Possible reasons for these findings are discussed.


Folate, folic acid and 5-methyltetrahydrofolate are not the same thing.

From: http://www.ncbi.nlm.nih.gov/pubmed/24494987


1. Folate, an essential micronutrient, is a critical cofactor in one-carbon metabolism. Mammals cannot synthesize folate and depend on supplementation to maintain normal levels. Low folate status may be caused by low dietary intake, poor absorption of ingested folate and alteration of folate metabolism due to genetic defects or drug interactions. 2. Folate deficiency has been linked with an increased risk of neural tube defects, cardiovascular disease, cancer and cognitive dysfunction. Most countries have established recommended intakes of folate through folic acid supplements or fortified foods. External supplementation of folate may occur as folic acid, folinic acid or 5-methyltetrahydrofolate (5-MTHF). 3. Naturally occurring 5-MTHF has important advantages over synthetic folic acid – it is well absorbed even when gastrointestinal pH is altered and its bioavailability is not affected by metabolic defects. Using 5-MTHF instead of folic acid reduces the potential for masking haematological symptoms of vitamin B12 deficiency, reduces interactions with drugs that inhibit dihydrofolate reductase and overcomes metabolic defects caused by methylenetetrahydrofolate reductase polymorphism. Use of 5-MTHF also prevents the potential negative effects of unconverted folic acid in the peripheral circulation. 4. We review the evidence for the use of 5-MTHF in preventing folate deficiency.

Is 5-methyltetrahydrofolate an alternative to folic acid for the prevention of neural tube defects?


Women have higher requirements for folate during pregnancy. An optimal folate status must be achieved before conception and in the first trimester when the neural tube closes. Low maternal folate status is causally related to neural tube defects (NTDs). Many NTDs can be prevented by increasing maternal folate intake in the preconceptional period. Dietary folate is protective, but recommending increasing folate intake is ineffective on a population level particularly during periods of high demands. This is because the recommendations are often not followed or because the bioavailability of food folate is variable. Supplemental folate [folic acid (FA) or 5-methyltetrahydrofolate (5-methylTHF)] can effectively increase folate concentrations to the level that is considered to be protective. FA is a synthetic compound that has no biological functions unless it is reduced to dihydrofolate and tetrahydrofolate. Unmetabolized FA appears in the circulation at doses of >200 μg. Individuals show wide variations in their ability to reduce FA. Carriers of certain polymorphisms in genes related to folate metabolism or absorption can better benefit from 5-methylTHF instead of FA. 5-MethylTHF [also known as (6S)-5-methylTHF] is the predominant natural form that is readily available for transport and metabolism. In contrast to FA, 5-methylTHF has no tolerable upper intake level and does not mask vitamin B12 deficiency. Supplementation of the natural form, 5-methylTHF, is a better alternative to supplementation of FA, especially in countries not applying a fortification program. Supplemental 5-methylTHF can effectively improve folate biomarkers in young women in early pregnancy in order to prevent NTDs.