Nearly 20 percent of drug-related liver injuries treated in hospitals are caused by supplements, according to a recent study. This is up from 7 percent a decade ago, Newsmax Health reports.

Many of these patients recover once they stop taking the supplements, but some require liver transplants or die, reports The New York Times.

 The new research found that many of the products causing liver injuries were bodybuilding aids that contained steroids as an unlisted ingredient. Herbal pills and powders promising to boost energy and weight loss were also implicated.

Green tea extract, in particular, was cited as causing liver problems. The extracts often contain catechins, powerful antioxidants that increase metabolism and supposedly aid in weight loss. But most green tea pills are highly concentrated and contain many times the amount of catechins that are in a cup of tea. In high doses, catechins can be toxic to the liver.