GDF11 vs Myostatin
Written by Aaron CuhaReviewed Sep 2026
The short answer
Two close cousins in the same protein family. One is famous for rejuvenation claims and one for muscle. Their likeness is not a side point. Lab tests mixing up the two are part of why the early GDF11 results did not hold up.
- GDF11 people
- 0
- GDF11 nulls
- 0
- Myostatin people
- 188
- Myostatin nulls
- 1
Dose
No human dose established
No published study on this page has given this compound to people and reported a result.
1 human study where nobody was given it
Dose
No human dose established
Amounts that were given in studies sit in Human evidence on this page. None of them is a personal dose.
3 completed trials, 188 people given it
First-hand reports are counted on each profile and never added together. This page sets two published records side by side. It does not pick a winner.
Column A
GDF11Growth/differentiation factor 11
GDF11 is the protein behind the young blood story. Two famous mouse papers in 2013 and 2014 said it drops with age and that topping it up makes old animals young again. A human test built to measure it properly found it does not drop with age, and higher levels went with frailty.
Column B
MyostatinMyostatin (growth/differentiation factor 8)
Myostatin is the body's brake on muscle growth. Mice bred without it grew two to three times more muscle, which started a whole field. In monkeys, though, a different protein turns out to be the main brake.
Side by side, on the facts we can check
| What we compare | GDF11 | Myostatin |
|---|---|---|
| Category | Anti-aging | Muscle & Performance |
| FDA status | Not an approved drug. No study has ever given GDF11 to people. | Myostatin is a protein the body makes, not a drug. Drugs that target it are investigational. Apitegromab has results from final-stage studies in spinal muscular atrophy. |
| Half-life | Circulates as a latent complex. No verified circulating half-life is asserted here. | Circulates as a latent complex; no single agreed circulating half-life is asserted here. |
| Molecular weight | Precursor 407 amino acids, 45,091 Da. Mature signalling domain is residues 299 to 407, 109 amino acids, the same length as myostatin's (UniProt O95390). | Precursor 375 amino acids, 42,750 Da. Mature signalling domain is residues 267 to 375, 109 amino acids, circulating as a dimer (UniProt O14793). |
| How it works | GDF11 uses the same receptor and the same signal inside the cell as myostatin. In heart muscle it sends that signal more strongly than myostatin does. The shared receptor and near-identical working part are not a side note. They are the direct cause of the fight over measuring it, because lab tests struggle to tell the two apart. | Myostatin travels in the blood in a locked, inactive form. Once unlocked, it docks on a receptor on muscle cells, mainly one called ActRIIB. That sends a signal inside the cell that slows muscle building and keeps muscle repair cells quiet. Activin A uses the same receptor. That is why blocking the receptor and blocking myostatin alone behave so differently. |
| Studies in people | 1 | 4 |
| Evidence | Preliminary: 1 human study where nobody was given it | Moderate: 3 completed trials, 188 people given it |
| Legal status, US | Not a drug; a natural body hormone, given only by drip in research | Not a drug; a natural body hormone, given only by drip in research |
Frequently asked questions
What is the difference between GDF11 and Myostatin?
GDF11: GDF11 is the protein behind the young blood story. Two famous mouse papers in 2013 and 2014 said it drops with age and that topping it up makes old animals young again. A human test built to measure it properly found it does not drop with age, and higher levels went with frailty. Myostatin: Myostatin is the body's brake on muscle growth. Mice bred without it grew two to three times more muscle, which started a whole field. In monkeys, though, a different protein turns out to be the main brake.
Which has stronger research evidence, GDF11 or Myostatin?
Each compound gets a band worked out from facts we counted, with the math shown. GDF11 is Preliminary (1 human study where nobody was given it). Myostatin is Moderate (3 completed trials, 188 people given it). That counts how much has been done in people. It does not rate whether either one works, and neither one is called the winner.
Are GDF11 and Myostatin FDA-approved?
GDF11: Not an approved drug. No study has ever given GDF11 to people.. Myostatin: Myostatin is a protein the body makes, not a drug. Drugs that target it are investigational. Apitegromab has results from final-stage studies in spinal muscular atrophy..
Reviewed Sep 2026. This page puts two published records side by side. It is for learning, and it is not medical advice. When this site shows a dose, it is the dose a trial or a clinic actually used, or what people say they did, with the source attached. None of it tells you what to take.