When to Supplement with Vitamin B6

National food surveys show that the median daily intake of vitamin B6 in the United States by men is nearly 2 milligrams, and for women it's about 1.5 milligrams - well within the recommended levels. B6 is not recommended for children.

While extreme B6 deficiency is rare (it's never been seen with intakes of 0.5 milligrams or more per day), marginal deficiencies are more likely. Certain groups are at a greater risk of deficiency, including the elderly, alcoholics, and women on high-dose oral contraceptives - although the studies done with contraceptives were conducted when the level of estrogen in the pill was three to five times higher than the oral agents used today.

When deficiencies occur, they are usually associated with other nutrient deficiencies. For example, since riboflavin is needed for the production of B6. The earliest symptoms of vitamin B6 deficiency are changes in the nervous system, which can be seen on an EEG. Severe deficiency may result in seizures, dermatitis, glossitis, cheilosis, stomatitis, and anemia.

Vitamin B6 supplementation has been used in the treatment of, or in an attempt to prevent, a number of diseases, including Down syndrome, autism, gestational diabetes (diabetes during pregnancy), premenstrual syndrome, CTS, and diabetic neuropathy. However, B6 supplementation has been of limited benefit in these circumstances. And in some cases, such as the treatment of premenstrual syndrome, supplementing with B6 has resulted in a small number of cases of neurotoxicity and photosensitivity. These symptoms are usually seen when doses above 500 milligrams per day used on a chronic basis.