Epicatechin (dark chocolate flavanol)

Tier 3 — weak evidence · Muscle growth · Blood flow · Myostatin inhibition

A flavanol found in dark chocolate and green tea that inhibits myostatin — a protein that limits muscle growth — in preclinical studies. A small 2014 trial found 1 mg/kg/day improved hand grip strength in sarcopenic older adults. Also improves endothelial function and blood flow through nitric oxide modulation. The COSMOS trial did not meet its primary cardiovascular endpoint but a secondary analysis showed a 27% reduction in CV mortality with 500 mg/day cocoa flavanols.

Dose: 1–2 mg/kg body weight/day (approximately 75–150 mg) from standardised epicatechin or high-flavanol cocoa extract