Many moderate smokers (those who smoke less than a pack per day) may have “unacceptably low” blood levels of vitamin B-6, say Washington State University researchers. B-6 is believed to be protective against the DNA damage that can lead to cancers. It is also well known to help protect against heart disease by lowering levels of homocysteine.

In a small study, smokers eventually reached acceptable blood levels of the vitamin after three months of consuming increasingly high levels of dietary and/or supplemental vitamin B-6. But they never caught up with their non-smoking counterparts. Considering B-6’s role in DNA synthesis and repair, these results further convinced the researchers that the current RDA for this critical vitamin is too low for even moderate smokers and could be too low for the population as a whole.

In several large population studies, people with a higher intake of vitamin B-6 were found to have a lower risk of colon, prostate, lung, gastric and pancreatic cancers. The good news from this study, say researchers, is that adding B-6 to the diet rapidly improved both smokers’ and non-smokers’ B-6 status and, equally rapidly, decreased the number of DNA strand breaks in both groups.

Vitamin B-6 has been identified as a nutrient that is often deficient in the general population. This study suggests smokers are even more likely at risk for low B-6 and thus for the problems it presents.

American Society for Nutritional Sciences, Apr 14, 2003