High doses of vitamin B6 and B12 supplements may increase the chances of lung cancer in males, especially for smokers, a new study says.
Researchers from the Ohio State University College of Medicine found an increase of 30-40% for lung cancer in men taking individual B6 and B12 supplements, not from multivitamins or diets. The effect was worse in smokers who exceeded the daily recommended amounts of vitamins, CNN reports.
Theodore Brasky, an epidemiologist in the division of cancer prevention and control at Ohio State, said there might be “a synergism” between smoking, high-dose vitamin B and lung cancer risk in men.
Male smokers who consumed the highest levels of vitamin B6 more than tripled their lung cancer risk over six years. For smokers takin B12, the risk was nearly fourfold higher.
Brasky said,
If you look at B-vitamin supplement bottles…they are anywhere between 50-fold the US recommended dietary allowance (to) upward of 2,100-fold.
In addition, B12 injections have become quite the trend, he added.
Both vitamins help certain processes in the body when taken in small amounts. But high-dose supplements nowadays claim to boost energy, among other unproven benefits. “That’s marketing. That’s not science,” Brasky noted.
The study involved around 77,000 adults in Washington state ages 50 to 76, including 139 cases of lung cancer among 3,200 male smokers. Over 93% of the respondents were white. There were not enough cases of lung cancer among non-smokers to include them, and there was no increased risk seen in either women or vitamin B9.
Focusing on vitamin B may not be the answer to protecting against this increase in lung cancer risk, Basky said. “Combustible tobacco smoke is the No. 1 most important factor, not just only in lung cancer but in many cancers.” He pointed out, “When we’re talking about what to be concerned about most: If you’re a male smoker and you want to take B vitamins, you can stop smoking. Smoking is the most important thing here, and that’s preventable.”
The study was published in the Journal of Clinical Oncology.
