Follistatin is a naturally occurring protein/peptide in the body that regulates several growth factors, most notably myostatin.

What it does

The main reason it gets attention in research is because it:

• Blocks myostatin – a protein that limits muscle growth

• Increases muscle development when myostatin is suppressed

• Binds activin proteins, affecting cell growth and hormone signaling

• Plays roles in muscle repair, fertility, inflammation, and metabolism

Why it’s researched

Researchers study follistatin for potential effects on:

• Muscle growth and recovery

• Muscle wasting diseases (like muscular dystrophy)

• Fat metabolism

• Tissue regeneration

• Anti-aging or performance research