Sermorelin

Sermorelin is a prescription peptide drug, not a dietary supplement ingredient, and it cannot be lawfully sold in the United States as a dietary supplement. Human trials do exist, which separates sermorelin from most peptides sold online, but almost all of them were run in the 1990s in children with growth hormone deficiency, and in that population sermorelin performed measurably worse than growth hormone itself (height velocity 9.2 to 9.3 cm/year on sermorelin versus 14.6 cm/year on growth hormone in a 60-child randomized trial, Chen 1993, PMID: 8329830). The evidence base for what people actually buy it for, meaning anti-aging, fat loss, muscle gain, recovery, and sleep in healthy adults, is thin to absent: the relevant adult trials enrolled roughly 10 to 20 older adults for 2 weeks to 16 weeks, and the one with the fullest body composition workup found no change in DEXA-measured muscle, fat, body weight, glucose, insulin, or lipids after 6 weeks of 2mg nightly, in an open trial with no placebo arm (Vittone 1997, PMID: 9005976). Tachyphylaxis is a documented and repeatedly observed problem: IGF-1 rose and then drifted back toward baseline by 16 weeks in one trial (Khorram 1997, PMID: 9141536), and 24-hour growth hormone output rose early and then fell back close to pre-treatment values by 6 months of continuous infusion in another, with 1 of 6 children showing complete suppression (Tauber 1993, PMID: 8329829). Anti-GHRH antibodies developed in 39 of 40 treated children in the Chen trial. There are no long-term safety data in healthy adults, no trials of sermorelin for longevity, cognition, or athletic performance, and it is prohibited in sport by the World Anti-Doping Agency (Memdouh 2021, PMID: 34665524). Anyone considering it should be doing so under a prescriber, not from a supplement label.