Category: polyphenol
Aliases: GTE, Polyphenon E, Sunphenon EGCG-rich extract
Polyphenolic extract of Camellia sinensis leaves — primary bioactives are the catechins (EGCG, EGC, ECG, EC) plus l-theanine + caffeine in non-decaffeinated extracts. EGCG is the dominant antioxidant + multi-target signaling modulator (NF-κB inhibition, AMPK activation, anti-angiogenic via VEGF/MMP). Caffeine + l-theanine provide a synergistic cognitive profile (caffeine vigilance + theanine's α-wave dampening of jitter). Standardized extracts are typically 40–95% total polyphenols with EGCG at 25–50% of the extract by mass. Hepatotoxicity risk above ~800 mg EGCG/d (EFSA 2018) — drives caps in supplement labeling.