The U.S. Food and Drug Administration is once again warning consumers to avoid muscle-building "supplements" that are anything but a safe alternative to steroids.

In an advisory sent out last week, the agency said it continues to ...

While taking vitamins may be fine for teens and young adults, supplements for weight loss, muscle-building and added energy may trigger severe medical problems, new research suggests.

Regulations to keep these potentially harmful products out of the hands of young people are urgently needed, the study authors said.

"The [U.S. Food and Drug Administration] has issued countles...

Men who abuse hormones such as testosterone or steroids for bodybuilding can have declines in sperm and testosterone production, researchers say.

The good news: these changes seem to reverse once men stop hormone overuse.

While the use of nonprescribed male hormones (androgens) has surged in many wealthy countries, there has been little research into their effect on men's r...