EFSA has assessed the safety of green tea catechins from dietary sources, following concerns regarding their possible harmful effects on the liver. The Authority concluded that catechins from green tea infusions and similar drinks are generally safe. When taken as food supplements, however, catechin doses at or above 800 mg/day may pose health concerns.
In its safety assessment, EFSA looked at possible links between the consumption of EGCG in green tea infusions and food supplements and liver damage.
For green tea infusions, EFSA’s experts concluded that there is generally no indication of liver damage even after high consumption, and that the few cases of liver damage reported in humans are likely due to rare and unpredictable reactions.
For food supplements, EFSA’s experts concluded – on the basis of human studies conducted with volunteers under medical supervision – that doses of EGCG at 800 mg/day may be associated with initial signs of liver damage. While there was no indication of liver injury for doses below 800 mg/day from green tea supplements, experts were unable to identify a safe dose based on available data.
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.