The European Food Safety Authority (EFSA) has concluded that catechins from green tea infusions and similar drinks are generally safe, however when taken as food supplement, it says that doses at or above 800mg/day might pose health concerns.
The study, triggered by reported cases of liver damage possibly associated with the use of green tea products, found that there was generally no indication of liver damage from infusions, even after high consumption, and that the few cases of liver damage reported in humans were probably due to rare and unpredictable reactions.
But the experts added that, on the basis of human studies conducted with volunteers under medical supervision, doses at or above 800mg/day may be associated with initial signs of liver damage. While they said there was no indication of liver injury for doses below 800mg/day from green tea supplements, the experts were unable to identify a safe dose based on available data.
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, explains the EFSA. It highlights that infusions tend to be consumed with food, with use spread out throughout the day, while supplements, especially for slimming, are more likely to be taken in a fasting state and as a single daily dose.
The EFSA has recommended that more studies be undertaken and has also proposed clearer labelling of green tea products (particularly food supplements) regarding catechin content and their possible health risks. The EFSA’s advice is now being forwarded to the European Commission, which will decide upon the most appropriate risk management follow-up.
Responding to the findings, Tim Gaunt, director of technical sales at Natures Aid, says: “The level that EFSA are currently stating is safe, ie 800mg per day, would be difficult to exceed using the supplements we currently offer that contain green tea. As long as consumers do not exceed the recommended number of tablets/capsules per day then the maximum dose of catechins that would be consumed on a daily basis would be 219mg (this is the catechin content of our green tea tablet) which is only a quarter of the safe dose. The EGCG level in this particular product is 141mg and so for Natures Aid this latest set of findings has no immediate concerns.”