Long Term Vitamin Use Tied to Significant Increase in Cancer Risk
According to results of an analysis involving participants of the Vitamins and Lifestyle (VITAL) cohort, long-term use of supplemental vitamins B6, folate, and B12 is not chemopreventive for lung cancer and may be harmful to patients.
A total of 77,118 patients aged 50 to 76 years were included in the study where “incident, primary, invasive lung cancers (n=808) were ascertained by prospectively linking the participants to a population-based cancer registry.” To analyze the exposure to both individual and multivitamin supplements, the 10-year average daily dose of each patient was assessed.
No association was found between lung cancer risk and supplemental use of vitamins B6, folate, and B12 in women. The study authors stated that, “in contrast, use of vitamin B6 and B12 from individual supplement sources, but not from multivitamins, was associated with a 30% to 40% increase in lung cancer risk among men.”
Upon evaluation of the 10-year average supplement dose, it was found that lung cancer risk increased almost 2-fold in men taking >20mg/day of vitamin B6 (HR: 1.82; 95% CI: 1.25, 2.65) and >55mg/day of vitamin B12 (HR: 1.98; 95% CI: 1.32, 2.97) versus nonusers. The study authors noted, that this risk was further increased in men who were smoking at baseline. Additionally, it was found that, “the B6 and B12 associations were apparent in all histologic types except adenocarcinoma, which is the type less related to smoking.”
Evidence from this analysis involving participants of the VITAL cohort not only found that supplementation with B vitamins is not chemopreventive, but that is also potentially harmful to patients.For more information visit Ascopubs.org.