Epicatechin

Compelling preclinical data on myostatin inhibition and NO signalling, but human muscle-building trials are small. The vascular benefits via cocoa flavanols are better supported.

A rough internal score reflecting quantity, quality, and consistency of human evidence. Not a clinical recommendation.

Inhibits myostatin and increases follistatin in rodents and small human studies. Increases NO bioavailability via eNOS activation. Part of the mechanism behind cocoa flavanol cardiovascular benefits. Dedicated epicatechin-only muscle studies are limited to pilot data.

• Increases nitric oxide bioavailability
• Myostatin inhibition in preclinical models
• Key active component in cocoa flavanol benefits

100–200 mg/day of purified epicatechin in pilot studies. 500+ mg cocoa flavanols provide ~80–160 mg epicatechin.

• GI discomfort
• Headache (rare)

Purified epicatechin products lack the long safety record of whole cocoa flavanol supplements.

Myostatin inhibition in small human studies doesn't yet translate to confirmed muscle gains. Most robust data are as part of cocoa flavanol mixtures.

• Longevity40
• Muscle32
• Energy28