A 17-year-old’s attempt to accelerate weight loss ended up causing so much liver damage he is now awaiting a transplant.

Christopher Herrera had bought concentrated green tea extract at a nutrition store as a “fat burner.” Herrera ended up weeks later at Texas Children’s Hospital with his chest, face and eyes so yellow that his doctor called it almost “highlighter yellow.”

A new study is showing that dietary supplements not regulated by the FDA account for almost 20 percent of liver injuries in hospitals. The number is more than double the 7 percent rate from a decade ago. Investigators say they were only counting “severe” cases of liver damage and were deliberately undercounting the total number of cases.

The FDA is banned from approving or evaluating most supplements before they enter the market because of the 1994 Dietary Supplement Health and Education Act. The FDA can only act until the items are on sale and in many cases only if people have been reported to be harmed by a supplement.

The FDA estimates 70 percent of dietary supplement companies do not follow basic quality control standards.