Green tea extract: what it is and how much people take

Green tea extract is a concentrated extract of tea leaves. It usually contains caffeine. Many studies exist, but firm conclusions cannot be drawn yet. For adults, the EU limit of under 800 milligrams of EGCG a day is the usual ceiling. Liver injury has been reported, mainly with extract pills; take it with food.

Checked 28 September 2026 · Source: NCCIH (US National Institutes of Health) · Adults only

General information, not medical advice. Check with a doctor or pharmacist before taking a supplement, especially if you are pregnant or breastfeeding, take any medicine, or are under 18.

How much people take

What studies looked atMany studies exist, but firm conclusions cannot be drawn yet.
Daily ceilingThe EU limit of under 800 milligrams of EGCG a day.

Cautions and interactions

Quick answers

What is green tea extract?
Green tea extract is a concentrated extract of tea leaves. It usually contains caffeine.
What has green tea extract been studied for?
Many studies exist, but firm conclusions cannot be drawn yet.
How much green tea extract is too much?
For adults, the EU limit of under 800 milligrams of EGCG a day is the usual ceiling.
Is green tea extract safe?
Liver injury has been reported, mainly with extract pills; take it with food. It can lower levels of some medicines, including nadolol and atorvastatin.

Sources

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