FREQUENTLY ASKED
Questions Readers Actually Ask
Short, cited answers pulled directly from the research pages on this desk.
What is semaglutide?
Semaglutide is a synthetic peptide that copies the human gut hormone GLP-1, modified to resist rapid breakdown so it can be dosed once weekly. It is FDA-approved for type 2 diabetes, chronic weight management, cardiovascular risk reduction in adults with existing heart disease, and, since 2025, a liver condition called MASH [1]. See the full semaglutide page for mechanism and trial detail.
How does semaglutide work for weight loss?
It activates GLP-1 receptors in appetite circuits in the hypothalamus and brainstem, reducing hunger signalling and the background preoccupation with food some people describe as 'food noise,' while also slowing stomach emptying. In its largest weight-management trial, participants lost a mean 14.9% of body weight over 68 weeks versus 2.4% on placebo [4].
What is thymosin alpha 1?
Thymosin alpha-1 is a 28-amino-acid immune-modulating peptide, sold internationally under the brand name Zadaxin (generic thymalfasin). It is approved as a medicine in more than 35 countries but does not hold FDA marketing approval in the United States [7]. See the thymosin alpha-1 page for its full regulatory and trial history.
Is thymosin alpha 1 FDA-approved?
No. Thymosin alpha-1 has never received FDA marketing approval in the United States, even though it is an approved medicine in more than 35 other countries [7]. US access is limited to investigational and compounding contexts.
What does thymosin alpha 1 do?
It acts on the interface between the immune system's fast, first-line response and its slower, targeted one, engaging Toll-like receptors on dendritic cells to drive T-cell maturation and antigen presentation, while also activating a regulatory pathway that keeps that response from running unchecked. It has been studied most extensively in chronic viral hepatitis, sepsis and as a cancer-therapy adjunct [7][9].
What does BPC-157 do in the body?
In animal studies, BPC-157 promotes new blood-vessel growth by up-regulating a receptor called VEGFR2, a mechanism linked to accelerated healing of tendons, the gastric lining, and other tissue in rodent models [16]. Human evidence remains extremely limited — only three small pilot studies exist as of the most recent review [14].
Is BPC-157 a growth hormone?
No. BPC-157 is not a growth hormone; it is a synthetic 15-amino-acid peptide derived from a gastric-juice protein. One proposed mechanism involves sensitizing growth-hormone-receptor signalling in tendon cells in animal studies, which is a different thing from being a growth hormone itself.
Does BPC-157 damage the liver?
A first-in-human intravenous safety pilot found no measurable changes in liver, cardiac, kidney, thyroid or glucose biomarkers in two healthy adults given doses up to 20 mg [13]. That is a very small sample, and a 2025 review notes that rigorous, large-scale human safety data are still lacking [14], so this question is not yet settled by robust human evidence.
What does the MOTS-c peptide do?
MOTS-c is a mitochondrial-encoded peptide that activates the cellular energy sensor AMPK, improving glucose handling primarily in skeletal muscle, and, under metabolic stress, moves into the cell nucleus to help regulate stress-response genes [22]. In mice, it has also improved exercise performance and helped prevent muscle wasting [18][21]. See the MOTS-c page for the full mechanism.
Is MOTS-c legal to buy?
MOTS-c is not approved as a medicine by any regulator and is sold only as a research chemical for laboratory use, not for human consumption. It is also treated as a prohibited substance in elite competitive sport by anti-doping authorities.
What are the negative side effects of MOTS-c?
There is no completed human interventional trial of MOTS-c, so no formally documented human side-effect profile exists. The compound's human data are limited to one observational cohort study of naturally circulating levels in people on hemodialysis [19], which does not describe administering the peptide or any resulting side effects.
How often do you inject MOTS-c?
There is no established human dosing schedule for MOTS-c, because no completed human interventional trial exists to define one. Animal studies use dosing regimens developed for mice, which cannot be responsibly extrapolated to a schedule for people; this page does not recommend one.