Smoking Lowers Vitamin B6 Levels

Apr 17, 2004 08:54 AM EDT

A recent study has found that smoking hinders the body’s intake of vitamin B6, a vitamin believed to offer protection against the DNA damage that can lead to cancers.

Higher numbers of DNA breaks

Researchers followed a group of subjects that was evenly comprised of smokers and nonsmokers. During the first 28 days of the study, the subjects were given controlled diets that contained only marginal amounts of vitamin B6. At the end of that time, all the participants had lower levels of vitamin B6 and higher numbers of DNA strand breaks.


During the second month, the subjects ate a carefully controlled diet that included 1.4 mg of vitamin B6 per day—some from food and some from supplements. In the third month, the vitamin B6 intake was increased to 2.2 mg a day.

Smokers’ levels never matched nonsmokers

For the final month, the participants were allowed to eat whatever they wished. However, they had to take 10.3 mg of vitamin B6 per day—more than seven times the recommended daily allowance.


The study found that as the amount of vitamin B6 in the diet and bodies increased the number of DNA strand breaks decreased. That pattern was seen as early as the first month of vitamin B6 supplementation. While the smokers' levels of vitamin B6 did increase, they never matched the vitamin B6 levels in the nonsmokers.

Foods high in vitamin B6 include cereals, chicken, fish, legumes, soy products and bananas.