The Center for Science in the Public Interest (CSPI) has followed through on its threat of a lawsuit against German drugmaker Bayer AG for claiming the amount of selenium contained in its One A Day vitamins may reduce a man's risk of prostate cancer.

What prompted the lawsuit: Two recent studies, including one prominently featured in The Journal of the American Medical Association that found selenium "did not prevent prostate cancer in this population of healthy men" and may have contributed to a diabetes diagnosis in some of them.

Although Bayer agreed to revise future marketing claims, the lawsuit was filed after Bayer refused to recall existing One A Day packaging and advertising touting the product's effect on prostate cancer. Bayer defended its position, arguing that its labeling followed existing FDA guidelines at that time.

The agency revised its guidance in June, however, requiring companies to include a disclaimer warning patients that it was highly unlikely selenium possessed any cancer-fighting advantages.

Bayer is also under scrutiny by attorneys generals in 27 states and federal regulators due to deceptive marketing charges.

CSPI Newsroom October 1, 2009

AboutLawsuits.com October 2, 2009

St. Petersburg Times October 2, 2009

New York Times October 1, 2009 Subscription Required

National Cancer Institute October 27, 2008

One A Day is a trademark of Bayer AG.