Fat Loss
Fat loss peptides
Metabolic and body-composition compounds studied for fat loss, including the GLP-1 class (Retatrutide, Semaglutide) and Tesofensine. Review the mechanism, evidence base, and contraindication notes before building a protocol.
Compounds in this category
How fat loss peptides work
Fat-loss peptides in this category are mostly incretin mimetics — they act on the GLP-1 receptor (and, in newer molecules, GIP and glucagon) that the gut and brain use to regulate appetite and energy balance. By amplifying these signals they reduce hunger, slow gastric emptying so meals feel more satisfying, and improve how the body handles glucose.
Because the effect compounds over time, these protocols run as a gradual titration — starting at a low weekly dose and stepping up every few weeks to balance results against side effects. Sustained fat loss comes from the lower energy intake this drives, paired with adequate protein and resistance training to protect lean mass.
Research context
The strongest evidence here is human and recent. In the Phase 3 STEP program, semaglutide 2.4 mg produced roughly 15% mean body-weight loss over 68 weeks. The triple-agonist retatrutide went further in the TRIUMPH trials — about 24% in general obesity and up to ~28% in higher-BMI cohorts at 68 weeks — the largest reductions recorded in a Phase 3 obesity trial to date.
Two things matter when reading those numbers: the timelines are long (most trials run 50–72 weeks, not a few weeks), and the results are averages — individual response varies with dose, adherence, diet, and starting point.
Safety considerations
These are clinician-supervised compounds, not casual supplements. The most common effects are gastrointestinal — nausea, reduced appetite, occasional constipation — usually worst right after a dose increase and eased by slower titration. GLP-1/GIP/glucagon agonists are contraindicated with a personal or family history of medullary thyroid carcinoma or MEN2, with active pancreatitis, and in pregnancy.
Baseline and periodic labs (HbA1c, fasting glucose, lipase) plus blood-pressure checks at each step are standard. Rapid weight loss can also cost muscle, which is why protein intake and resistance training are part of every protocol here.
Educational information only — not medical advice, a diagnosis, or a prescription. Peptides discussed here should be used under the supervision of a licensed clinician.
Related compounds & protocols
Frequently asked questions
How fast will I see results?
Appetite usually drops within the first couple of weeks, but meaningful body-weight change accumulates over months — the clinical trials ran 50–72 weeks. Expect a gradual, titrated curve rather than an overnight change.
Are these the same as Ozempic and Wegovy?
Semaglutide is the molecule in Ozempic and Wegovy. Retatrutide is a newer, more potent triple agonist still completing trials. Pepzilla is an education and personalization platform, not a pharmacy — we explain the compounds and protocols; dispensing and prescribing happen through licensed clinicians.
Will I lose muscle?
Some lean-mass loss accompanies any large calorie deficit. Adequate protein (about 1.6 g/kg/day) and resistance training 2–3× per week meaningfully reduce it, and a growth-hormone-axis companion is sometimes added for muscle preservation.
Do I need a prescription?
Yes — GLP-1-class peptides are prescription compounds and should be used under clinician supervision. Pepzilla helps you understand the options and build a structured plan to discuss with a provider.