While green tea supplements claim to help with weight loss, Consumer Reports experts said there is very little evidence to support them.
The experts reveal the potentially serious health risks of those supplements.
You may have heard green tea is good for you, but don't confuse drinking a cup of green tea with green tea extract powder.
"Higher concentrations of green tea extract can be really dangerous because it can potentially cause serious liver damage. Plus the herb itself has been found to alter the effectiveness of a long list of drugs, including certain anti-depressants and anti-clotting medications," said Jeneen Interlandi with Consumer Reports.
It can also elevate your heart rate and blood pressure. Researchers suggest that up to 10 percent of people who suffer acute liver failure from green tea extract could die as a result.
Consumer Reports put green tea extract powder on its list of 15 supplement ingredients to avoid.
"The manufacturers who make these supplements are not required to prove to federal regulators that their products are safe, that they're effective or even that they are accurately labeled, so you really don't know what you're buying," Interlandi said.
Studies have also found even in high doses, green tea probably won't help you lose weight.
"It's true that green tea can raise your metabolic rate, so you burn more calories, but that's probably just due to its caffeine and catechins it contains. Catechins are antioxidants that are found in green tea," Interlandi said.
Experts say most people can reap the health benefits of green tea by drinking a couple cups a day.
Consumer Reports has long advocated for measures that would improve supplement safety and give the FDA greater authority to remove potentially harmful dietary supplements from the marketplace.
For now, check out Consumer Reports list: www.consumerreports.org/15-supplement-ingredients-to-always-avoid/. It includes green tea extract powder, kava and caffeine powder.