Are semaglutide and tirzepatide really peptides?
Yes. Both are lab-made peptides, short chains of amino acids modeled on gut hormones, and they have far more weight-loss data than anything sold as a “fat-loss peptide.” The Wegovy label describes semaglutide as a GLP-1 analog with 94% sequence similarity to the human hormone, built on a peptide backbone. Tirzepatide is a peptide that acts on two hormone receptors, GIP and GLP-1.
The results come from large, controlled trials. On semaglutide 2.4 mg, adults in the main weight trial lost 14.9% of body weight over 68 weeks, against 2.4% on placebo. In a SURMOUNT-1 body composition substudy, people on tirzepatide lost 21.3% of body weight at 72 weeks, and about three quarters of that loss was fat. Both are FDA-approved for weight management, with labels, dosing schedules and known side effects.
Where does tesamorelin fit?
Tesamorelin fits a narrow job: shrinking visceral fat, the deep fat around your organs, without changing overall weight much. It is a growth hormone-releasing factor analog, approved as Egrifta to reduce excess abdominal fat in adults with HIV-associated lipodystrophy. Use for belly fat in men without HIV is off-label.
The Egrifta WR label reports visceral fat falling 18% over 26 weeks in one trial, against a 2% rise on placebo, and notes that the effect faded when people switched to placebo. It also states plainly that tesamorelin is not indicated for weight loss management because it is weight-neutral. Outside HIV, a 12-month randomized trial in 60 abdominally obese adults with reduced growth hormone found visceral fat fell 16 cm² on tesamorelin while it rose 19 cm² on placebo, with no change in the fat under the skin and no worsening of blood sugar.
The label also lists real cautions: it is not used with active cancer or pituitary disorders, it can cause glucose intolerance, and IGF-1 needs monitoring. Our comparison of tesamorelin and GLP-1 medicines for visceral fat sets the two approaches side by side, and the IGF-1 monitoring page explains the lab side.
Why is AOD-9604 off the table?
AOD-9604 is off the table because it is not eligible for compounding and the FDA has raised safety concerns about it. On the FDA’s page on bulk substances that may present significant safety risks, current as of April 22, 2026, the agency lists possible immune reactions, problems with peptide impurities, very little safety information, and serious adverse events that may be linked to it, though cause is unclear.
It is not an approved drug either, so there is no labeled product to fall back on. What remains is research-grade powder, which brings its own risks; our article on research-use-only peptides explains why that route is a gamble with your health.
What about other peptides sold for fat loss?
Most peptides marketed for fat loss online have little human evidence for it. CJC-1295 and ipamorelin, often sold as a pair, are not compoundable and are not offered at Ultimate Male. BPC-157 and TB-500 are recovery peptides with an unsettled regulatory path in 2026, not weight loss treatments. If a product promises fat loss without a label, a trial or a licensed pharmacy behind it, treat that as the answer.
How Ultimate Male matches a peptide to the goal
At our San Gabriel and Downey clinics, the question is not which peptide is trendy but what you are trying to change. If the goal is losing weight and you qualify, the conversation centers on semaglutide or tirzepatide through the medical weight loss program. If your weight is close to goal but labs and a scan point to stubborn visceral fat, your provider may discuss off-label tesamorelin, with IGF-1 and blood sugar checked along the way.
Every plan starts with labs and a one-on-one consultation with a PA-C or MD, and you hear the FDA status of anything recommended before you decide. Browse the full peptide therapy menu or call 626-319-5261 for a free 10-minute phone call.
