MOTS-c vs SS-31
There is no winner on this page. What is set side by side is the published record behind each one, which is the part the two are rarely compared on.
Both in Mitochondria and cellular energy
One of these has a real human dose behind it. SS-31's 40 mg a day under the skin is the dose in five published trials and on the approved label, and where the convention departs, it departs downward. MOTS-c has nothing to compare against: every dose in the record was given to a mouse, into the abdominal cavity, and the one completed human trial used CB4211, a modified version. The 2021 paper sold as a human trial of it gave the ten men no peptide at all, and measured how much their own bodies were already making.
| Field | MOTS-c | SS-31 |
|---|---|---|
| What a trial gave | No human dose has ever been publishedEvery published dose is a mouse dose, 0.5 to 15 mg per kg per day | 40 mg a day under the skinFive published trials and the approved label, every one in people with a diagnosed disease |
| What circulates | 5 to 10 mg per dose, two or three times a week up to daily | 0.1 to 40 mg a day under the skin |
| The gap | No studied dose to compare | Below the studied dose |
| How long it lasts | I found no published study of how long an injected dose lasts, in any species. Sellers give three different answers, and the four hour figure that circulates is usually credited to what are called the University of Southern California gerontology trials, which do not appear to exist. | This entry publishes no figure for how long it lasts in the body. What it reports instead is how fast the effect came and went: after a single two hour infusion into a vein, a laboratory measure of energy production rose immediately afterwards and the difference was gone by day 7. |
| Route studied | Into the abdominal cavity, in mice. Lee 2015 and Reynolds 2021 both injected it there. | Injected under the skin once a day at 40 mg in the later trials, and infused into a vein by body weight in the earlier ones. The mouse ageing result used an injection into the abdominal cavity, a route people do not use. |
| Route used | Under the skin. No study in mice that showed an effect used that route. | Injected under the skin from grey market vials, daily to three times a week, sometimes in cycles that one vendor page itself admits are not scientifically established. |
| Vial sizes | 10, 40 mg | 10, 50 mg |
The distance, stated
No studied dose to compare
MOTS-c
There is nothing to compare against. Every dose in the record was given to a mouse, into the abdominal cavity, and the one completed human trial used CB4211, a modified version rather than MOTS-c itself. Vendors say they reached the number by scaling the mouse doses by body surface area, and running that conversion on the 15 mg per kg dose does not land at 5 to 10 mg.
Below the studied dose
SS-31
The headline number is real for once. Forty milligrams a day under the skin is the dose in five published trials and on the approved label, and every one of those was in people with a diagnosed disease. Where the convention departs, it departs downward. I could find no human trial reporting a clinical result at 2, 5 or 10 mg a day, and the label mentions that lower range only as a span over which blood levels were measured, so somebody has given 2 mg a day and published nothing but the blood levels. I looked for a study in any species testing the three times weekly schedule several pages give, and could not find one.
What people get wrong
MOTS-c
The costly mistake is reading a measurement as a trial. In the 2021 paper, ten sedentary young men, average age about 24, rode a stationary bicycle to exhaustion, and the amount of MOTS-c their own bodies were already making rose 11.9 fold in muscle and 1.5 fold in blood, returning to normal within four hours. The men received no peptide at all. Measuring how much of a substance is already inside somebody is a completely different kind of evidence from giving it to them and watching what happens, and that study is routinely sold as a human trial of the injection. The same error runs the other way with CB4211, the modified version tested in the one completed trial, whose final group of 20 obese people with fatty liver got 25 mg once daily for four weeks, which is 2.5 to 5 times the amount people inject of a molecule that is not the same thing.
SS-31
Treating the approval as though it covers what is in the vial. What was approved is one salt, elamipretide hydrochloride, and a salt is the same active molecule paired with a partner that makes it a stable powder, which a regulator treats as its own product. Most bulk powder sold to compounding pharmacies is the acetate, and eighty days after the approval the American drug regulator wrote to a Florida distributor naming elamipretide (SS-31) acetate as ineligible for compounding. In that listing the active ingredient named in the filing was something called peptide B27PD. I could find no published comparison of the two salts in people, and nothing describing what peptide B27PD is.
Every figure above is carried across from each compound’s entry, which is where the citations live.
All 65 compounds on one page at what circulates vs what was studied, or pick another two to compare.