MedicalResearch.com Interview with:
Theodore M. Brasky, PhD
Research Assistant Professor
The Ohio State University – James Comprehensive Cancer Center
Columbus, OH 43201
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Prior literature has been suggestive of both a protective and harmful effect of certain B vitamins on lung cancer risk. We wanted to examine the association of intakes of vitamins B6, folic acid (B9), and B12 from supplements –which are typically taken at very high doses– and lung cancer risk in a large, prospective study of 77,000 men and women living in Washington State. The study is unique as it was designed specifically to examine associations of dietary supplements with cancer occurrence. We found that men who took high doses of vitamin B6 and B12 from individual supplements over a long period of time (meaning, doses much higher than the US RDA and much greater than what one would receive from taking a multivitamin over the long term) were at nearly 2-fold increased risk of lung cancer compared to men who did not have B6 or B12 intake from any supplemental source. This finding of increased risk appeared to be specific to men who were current smokers. Among them, long term high-dose supplementation was associated with 3-4 fold increases in lung cancer risk. We observed no increased risk for any of the supplements – B6, B12, or folic acid – with lung cancer risk in women or women who smoked.