Taking high doses of supplements containing green tea extracts may be associated with liver damage, according to new research from the European Food Safety Authority (EFSA).
Tea infusions, as used for brewed tea, are considered safe. Instant tea drinks are also fine as they contain lower levels of the antioxidants naturally present in green tea, Parma-based EFSA said.
Consuming too many of these antioxidants can be harmful, which is why the amount contained in supplements can have a harmful effect on the liver.
Most supplements provide an intake of 5-1000 mg, while tea infusions typically only contain 90-300 mg, EFSA, which oversees food safety in the EU, said.
Researchers said consuming over 800 mg per day led to higher health risks, but the EFSA said experts could not yet determine a dosage that would be entirely safe. However, high consumption of green tea infusions did not indicate liver damage due to the drinks having a lower concentration of antioxidants.
EFSA’s assessment of green tea catechins was triggered by concerns from Nordic countries following reported cases of liver damage possibly associated with the use of green tea products.
Catechins are present in green tea, the most abundant of which is epigallocatechin gallate (EGCG). EFSA looked at links between the consumption of EGCG in green tea infusions and food supplements and liver damage.
Catechins in green tea extracts used in food supplements may be more concentrated, or have a different composition and pattern of consumption compared to catechins from green tea infusions. For example, infusions tend to be consumed together with food, while supplements, especially for slimming, are more likely to be taken in a fasting state and as a single daily dose. AGENCIES