Klotho vs GDF11
Written by Aaron CuhaReviewed Sep 2026
The short answer
Two proteins that made longevity headlines and then met better measuring. Nobody has given klotho to a person in a published trial. The human test built to measure GDF11 properly found it does not drop with age, and that higher levels go with frailty.
- Klotho people
- 0
- Klotho nulls
- 0
- GDF11 people
- 0
- GDF11 nulls
- 0
Dose
No human dose established
No published study on this page has given this compound to people and reported a result.
2 human studies where nobody was given it
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
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
KlothoAlpha-Klotho (secreted s-KL) and klotho-based therapies
Nobody has given klotho to a person in a published study. People with higher blood levels tend to live longer and think better. A gene therapy is heading toward studies in people. Products sold online as klotho peptide are not the protein that was studied.
Column B
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.
Side by side, on the facts we can check
| What we compare | Klotho | GDF11 |
|---|---|---|
| Category | Longevity | Anti-aging |
| FDA status | No approved product; a gene therapy that has not yet asked the FDA to start human studies (pre-IND) | Not an approved drug. No study has ever given GDF11 to people. |
| Half-life | Endogenous protein; therapeutic forms not yet defined in humans | Circulates as a latent complex. No verified circulating half-life is asserted here. |
| Molecular weight | 116,181 Da for the 1,012 amino acid alpha-klotho protein (UniProt Q9UEF7); products sold as 'klotho peptide' are short fragments, not this protein | 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). |
| How it works | Loose klotho in the blood works with the hormone FGF23. It also tunes the insulin and IGF-1 signals, the Wnt signal, and the body's defence against oxidation. Its drop with age is linked to ageing of the kidneys, blood vessels and brain. | 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. |
| Studies in people | 2 | 1 |
| Evidence | Preliminary: 2 human studies where nobody was given it | Preliminary: 1 human study where nobody was given it |
| Legal status, US | Not approved; research use only | Not a drug; a natural body hormone, given only by drip in research |
Frequently asked questions
What is the difference between Klotho and GDF11?
Klotho: Nobody has given klotho to a person in a published study. People with higher blood levels tend to live longer and think better. A gene therapy is heading toward studies in people. Products sold online as klotho peptide are not the protein that was studied. 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.
Which has stronger research evidence, Klotho or GDF11?
Each compound gets a band worked out from facts we counted, with the math shown. Klotho is Preliminary (2 human studies where nobody was given it). GDF11 is Preliminary (1 human study where nobody was 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 Klotho and GDF11 FDA-approved?
Klotho: No approved product; a gene therapy that has not yet asked the FDA to start human studies (pre-IND). GDF11: Not an approved drug. No study has ever given GDF11 to people..
Related posts
Blog articles that cover Klotho or GDF11, newest first.
- Longevity / Sep 27, 2026 / 12 minPeptides for Longevity: What the Evidence Actually Shows in 2026
- Research / Sep 27, 2026 / 11 minNew Peptides and Longevity Compounds in 2026: What Is Actually New, What Is Newly Legal, and What Is Just New to Vendors
- Longevity / Sep 27, 2026 / 8 minKlotho Explained: Protein, Peptide, Gene Therapy or Supplement?
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.