B (6&12) careful!

August 25, 2017. In case you didn’t know, there is mounting evidence that taking high doses of vitamin B6 and B12 can nearly double a man’s risk of developing lung cancer. The most recent data comes from an analysis of the prospective VITAL cohort study published in JCO this week. The original idea was that B vitamins are involved in one-carbon metabolism, which, when deficient, can result in DNA damage. So supplementation should be good, right? Wrong. A surprising 2009 JAMA pub first noted increased lung cancer and cancer mortality among patients randomized to vitamin B12 and folic acid supplementation in a prospective trial designed to reduce cardiovascular events. This week’s report supports these findings specifically among men and the use of individual B6 and B12 supplements. This matters because over half the U.S. population reports using a supplement...especially when trying to be particularly health conscious during cancer treatment. So here’s yet another reason that patients without a documented deficiency should be directed to ditch the dietary supplements.