Browse evidence-based analysis of health-related claims and assertions
When scientists changed two specific letters in the MOTS-c peptide, it stopped working—proving those spots are essential for its sugar-burning effect.
Mechanistic
A few days of MOTS-c shots in mice lowered levels of two proteins linked to inflammation, hinting it might help calm down the body’s immune response.
Correlational
The MOTS-c peptide is almost the same in humans, mice, rats, and other animals—especially in four key spots—meaning evolution kept it because it’s important for how the body uses energy.
Descriptive
MOTS-c made muscle cells produce more GLUT4 (a sugar transporter) and turned on AMPK (an energy sensor), two key players in how muscles use sugar.
When cells made more MOTS-c, they stopped using oxygen as much and started using sugar instead—even though their mitochondria were still intact.
Old mice that got MOTS-c injections responded to insulin just as well as young mice, meaning the peptide might fix the insulin resistance that comes with aging.
When scientists removed the mitochondria’s DNA from human cells, the MOTS-c peptide disappeared—proving it comes from the mitochondria, not the cell’s main DNA.
Scientists found MOTS-c in the blood of humans and mice, and when they fasted, the levels dropped—hinting it might be a hormone that tells the body how to use energy.
Mice given MOTS-c burned more sugar for energy and produced more body heat—even though they didn’t move around more than the control mice.
As mice get older, their bodies make less of a peptide called MOTS-c, especially in muscles and blood—and when they fast, levels drop too, hinting that this peptide responds to energy needs.
When scientists added MOTS-c to cells in a dish, the cells started using more sugar for energy and turned on a key energy sensor called AMPK—until they added folic acid or blocked AMPK, which stopped the effect.
Mice that ate a fatty diet and got daily MOTS-c shots didn’t get as fat as mice that didn’t get the shots—even though they ate the same amount of food.
When mice were given a daily shot of a peptide called MOTS-c, their bodies became better at using sugar for energy and responding to insulin, especially in their muscles.
This drug only helped people whose belly fat went down a lot—so if your belly fat didn’t shrink, we don’t know if it would help your muscles.
Rising IGF-1 levels helped explain some of the muscle growth from the drug, but not all of it—so other factors are also at work.
Even though the drug raised IGF-1, that didn’t predict whether muscles got less fatty—so fat reduction in muscle must be happening through a different pathway.
Even when accounting for changes in growth hormone levels, these muscles still got bigger, meaning the drug works through other pathways too.
Causal
Even after accounting for belly fat loss, the muscles along the spine got denser with this drug, meaning it directly improved spinal muscle health.
The drug made the lean parts of the abdominal and rectus muscles denser—meaning they had less fat inside them—more than other muscles, showing it targeted key core muscles.
The muscle growth from this drug wasn’t because belly fat went down—it was more likely due to a rise in a growth-related hormone called IGF-1.
When belly fat went down in these patients, their trunk muscles also got less fatty—suggesting the same process might be cleaning up both types of fat.
The drug made two key core muscles—rectus and psoas—slightly bigger, adding about half a square inch each after six months, while the placebo group didn’t change.
This drug didn’t just make muscles less fatty—it also made them bigger in size, adding about half a square inch of lean muscle in the core area after six months.
For HIV patients with belly fat who responded to this drug, taking tesamorelin for 6 months made their trunk muscles less fatty and more dense, like turning soft muscle into firmer muscle.