Can green tea extract hurt your liver?

Possibly. In late 2017, Health Canada issued an updated warning about potential liver toxicity from green tea extract. The warning advises anyone taking green tea extracts, particularly those with liver disease, to watch for any signs of liver damage. It also urges children to avoid using products containing green tea extract.

Green tea extract is available in many forms, including capsules, tablets, powders, and liquids. Even among similar formulations, green tea extract often contains varied amounts of active constituents. One such constituent is epigallocatechin gallate (EGCG). The amount of EGCG in a daily dose of green tea extract can range from 5 mg to 1000 mg. Based on safety assessment of green tea products, the European Food Safety Authority recently found that green tea supplements providing more than 800 mg of EGCG per day are linked with a greater risk of liver injury.

Keep in mind that this possible risk of liver injury relates to green tea EXTRACT. Green tea as a beverage is almost certainly safe for the vast majority of people because it contains less EGCG than extract. Drinking green tea in normal amounts provides only 90 mg to 300 mg of EGCG per day. Also, green tea is usually consumed along with food and throughout the day. This tends to make the amount of EGCG in green tea less concentrated. On the other hand, doses of green tea extract are often taken all at once, sometimes on an empty stomach. This increases the concentration of EGCG in extracts compared to beverages.

Advise patients with liver disease to talk to their provider before taking products with green tea EXTRACT and to keep an eye out for any signs of liver damage, including jaundice, dark urine, sweating, or stomach pain. But let them know that drinking green tea BEVERAGES is almost certainly safe.