Taking too much vitamin B6 and B12 could dramatically increase lung cancer in men, according to a new study.

By looking at more than 77,000 patients over 10 years, researchers found men who consumed high doses of B6 and B12 (often advertised as an energy-booster) doubled their risk of developing lung cancer. In men who smoked, the risk increased four times, according to results published in the Journal of Clinical Oncology Tuesday. Women who took the same amount of vitamin B didn't see an increased risk.

The National Institutes of Health recommends adults only consume about 1.5 milligrams of vitamin B6 a day and 2.4 micrograms of vitamin B12. But, vitamin B supplements are available up to 5,000 micrograms per dose. A microgram is one-millionth of one gram.

“It’s very easy to get all the vitamin B you need in this country, from eating meats, chickpeas and foods like cereal that are fortified with them, so there really is no reason to supplement your vitamin B intake at these levels, and certainly not for years on end,” Theodore Brasky, who led the study at The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, said in a statement.

This research comes after a 2010 study suggested taking vitamin B supplements could lower the risk of lung cancer.