Vitamin B-6 is needed in more than 100 chemical reactions in the body and for forming amino acids, red blood cells, vitamin B-3 and antibodies. It is also important for nerve and brain function, as well as energy production.

How Much: Recommended dietary allowance (RDA) = 1.3 milligrams (mg) for all adults up to age 50; age 50 and older, 1.7 mg for men, 1.5 mg for women. 

Too Much: Tolerable upper limit (UL) = 80 mg for adults up to age 50; age 50 and older, 100 mg. Long-term use of more than 100 mg per day from supplements can temporarily damage nerves in the arms and legs.

Too Little: Rare; symptoms include skin inflammation, swollen tongue, depression, confusion and convulsions. Lower than optimal levels are linked to high levels of homocysteine, which can increase the risk of stroke and heart disease. 

Foods: Chickpeas; fish, chicken, turkey; potatoes; and most fruits except citrus. 

Interactions:  Drugs for epilepsy, tuberculosis and asthma. 

Research Note:  Low vitamin B-6 levels are common in people with rheumatoid arthritis (RA); levels drop as inflammation increases. In one study, taking 100 mg of vitamin B-6 and 5 mg folic acid daily for 12 weeks reduced inflammatory markers in the blood, but other studies don’t support this finding.