You must read and accept the disclaimer to use this site. Updated for monthly, 2011

You must read and accept the disclaimer to use this site.

SUMMARY: The Feb. 4, 1998 study in JAMA is consistent with the conclusion that getting about 800 mcg of folate daily may safely reduce the risk of heart disease by about 50% in non- drinkers, and 80% in those who have 2 or more alcoholic drinks daily. Getting 4.6 mg of vitamin B6 may reduce the risk of heart disease by 30%. These levels are almost double the current Daily Values established by the Food and Nutrition Board.

Folate, also called vitamin B9, is essential in the diet so that enzymes in your body can carry out a variety of chemical reactions necessary to transfer one carbon fragments of molecules essential to good health. It interacts with vitamin B12 in normal synthesis of DNA. People deficient in folate cannot convert the nucleic acid uracil into thymine and therefore have higher levels of DNA mutations (ref) which may cause birth defects (ref), cancer and other age- associated diseases. Folate, in combination with vitamins B6 and B12, is necessary for proper amino acid metabolism. Those deficient in folate have higher levels of homocysteine in the blood. Just as high cholesterol is a clear indication of higher risk for heart attacks, high homocysteine level is an independent risk factor for heart attacks (ref). To reduce your risk for heart attacks and cancer, and for women of childbearing age the risk of birth defects, you should obtain an adequate supply of folate through diet or supplements.

Structure:

Daily Value: 400 mcg (recently revised upward by the Food and Nutrition Board from 200 mcg)

Average intake from diet: Men: 706 micrograms (mcg) Women: 596 mcg (ref) However, these values conflict with a more recent study indicating that the average intake in a study of 80,082 nurses had an average intake of only 278 mcg (ref). The lowest 20% had daily intakes of only 153 mcg/day. The highest 20% had daily intakes of 774 mcg per day.

Hazardous level: 10 mg per day = 10,000 mcg (ref)

Commentary:

1. The data on consumption are confusing at best. Is the average intake 596 mcg or 278 mcg for women? Given that folate consumption is safe up to 10,000 mcg/day, and that it is proven to be likely to reduce the risk of birth defects in pregnant women and DNA mutations which could lead to cancer in older men, taking supplemental folate seems justified by current scientific and medical studies.

2. An important concern: One reason the Food and Nutrition Board and Food and Drug Administration are concerned about folate supplements is that adequate folate can mask vitamin B12 deficiency.

3. Why has the Daily Value been raised from 200 to 400 mcg? There is overwhelming evidence that folate reduces the risk of birth defects.

4. How much should one take? The February 4, 1998 study as part of the Nurses' Health Study, one of several major nutrition initiatives sponsored by the National Institutes of Health, indicates that heart attack risk decreases with increased folate consumption. The relative risk for coronary heart disease among 80,082 nurses in the study were as follows:

Median Daily Folate intake (mcg) 158 217 276 393 696

Relative Risk of Heart Disease 1.0 0.76 0.72 0.61 0.53

even lower risk for heart disease, 53% with an intake of 696 mcg vs. 61% risk with an intake of 393 mcg. The study states "the association between folate and homocysteine appears to plateau between 400 mcg/day and 1,000 mcg/day".

For those who drink alcohol, the results are even more stunning. Digestion (oxidation) of alcohol can inactivate folate. Their are many reports that moderate drinking (1 to 3 drinks per day) may be good for your health, but this study shows that folate is also very important. The risk for coronary heart disease for those in the study with the lowest folate intake and who do not drink alcohol (our control group) was defined as the standard risk. Those who consumed more than 1 drink of alcohol per day, with the same folate intake, had 18% less chance of getting heart disease. But those who consumed more than 1 drink per day AND consumed an average of 774 mcg of folate (vs. 153 for the control group) had a 78% lower risk of heart disease, nearly a five- fold decline!

My personal conclusion is that around 700 mcg is a safe and proven dosage, 75% higher than the US Daily Value. It is especially important for women of childbearing age, those who drink alcohol, and those at risk for cancer and heart disease to obtain an adequate intake of folate.

Similar evidence was found for vitamin B6, indicating that a safe and proven dosage for vitamin B6 is 4.6 mg per day, for which the Daily Value is only 2 mg.