EGCG
The most-studied antioxidant in matcha.
Also known as: epigallocatechin gallate, catechin
EGCG (epigallocatechin gallate) is a catechin — a class of antioxidant — and the most-researched compound in green tea. Matcha contains EGCG at roughly 60 mg per gram, far more than steeped green tea because you ingest the whole leaf. EGCG is studied for cardiovascular, metabolic, and neuroprotective effects; the science is promising but not conclusive. Practically: matcha is one of the more antioxidant-dense things you can drink.