NEW YORK — When Christopher Herrera, 17, walked into the emergency room at Texas Children’s Hospital one morning last year, his chest, face and eyes were bright yellow — “almost highlighter yellow,” recalled Dr. Shreena S. Patel, the pediatric resident who treated him.
Christopher, a high school student from Katy, Texas, suffered severe liver damage after using a concentrated green tea extract that he had bought at a nutrition store as a “fat burning” supplement. The damage was so extensive that he was put on the waiting list for a liver transplant.
“It was terrifying,” he said. “They kept telling me they had the best surgeons, and they were trying to comfort me. But they were saying that I needed a new liver and that my body could reject it.”
New data suggests that his is not an isolated case. Dietary supplements account for nearly 20 percent of drug-related liver injuries that turn up in hospitals, up from 7 percent a decade ago, according to an analysis by a national network of liver specialists.
The research included only the most severe cases of liver damage referred to a representative group of hospitals around the country, and the investigators said they were undercounting the actual number of cases.
While many patients recover once they stop taking the supplements and receive treatment, a few require liver transplants or die because of liver failure. Naive teenagers are not the only consumers at risk, the researchers said. Many are middle-aged women who turn to dietary supplements that promise to burn fat or speed up weight loss.
“It’s really the Wild West,” said Dr. Herbert L. Bonkovsky, the director of the liver, digestive, and metabolic disorders laboratory at Carolinas HealthCare System in Charlotte, N.C. “When people buy these dietary supplements, it’s anybody’s guess as to what they’re getting.”
Although doctors were able to save his liver, Christopher can no longer play sports, spend much time outdoors, or exert himself. He must make monthly visits to a doctor to assess his liver function.
Americans spend an estimated $32 billion on dietary supplements every year, attracted by unproven claims that various pills and powders will help them lose weight, build muscle, and fight off everything from colds to chronic illnesses. About half of Americans use dietary supplements, and most of them take more than one product at a time.
Dr. Victor Navarro, the chairman of the hepatology division at Einstein Healthcare Network in Philadelphia, said that while liver injuries linked to supplements were alarming, he believed that a majority of supplements were generally safe.
Most of the liver injuries tracked by a network of medical officials are caused by prescription drugs used to treat things like cancer, diabetes, and heart disease, he said.
But the supplement business is largely unregulated. In recent years, critics of the industry have called for measures that would force companies to prove that their products are safe, genuine, and made in accordance with strict manufacturing standards before they reach the market.
But a federal law enacted in 1994, the Dietary Supplement Health and Education Act, prevents the Food and Drug Administration from approving or evaluating most supplements before they are sold. Usually the agency must wait until consumers are harmed before officials can remove products from stores.
Because the supplement industry operates on the honor system, studies show, the market has been flooded with products that are adulterated, mislabeled, or packaged in dosages that have not been studied for safety.
The new research found that many of the products implicated in liver injuries were body-building supplements spiked with unlisted steroids and herbal pills and powders promising to increase energy and help consumers lose weight.
“There unfortunately are criminals that feel it’s a business opportunity to spike some products and sell them as dietary supplements,” said Duffy MacKay, a spokesman for the Council for Responsible Nutrition, a supplement industry trade group. “It’s the fringe of the industry, but as you can see, it is affecting some consumers.”
More popular supplements like vitamins, minerals, probiotics and fish oil had not been linked to “patterns of adverse effects,” he said.
The FDA estimates that 70 percent of dietary supplement companies are not following basic quality control standards that would help prevent adulteration of their products.