Not medical advice. Talk to your provider before using any peptide.
Full disclaimerBest Peptides for Weight Loss
Peptide Schedule Research Team
The most effective peptides for fat loss and appetite suppression — from FDA-approved GLP-1 agonists to targeted fat-burning fragments.
Expert Protocols
Verified protocols from researchers, physicians, and creators who have publicly disclosed their dosing.
Physician prescriber who flagged 39% lean mass loss in STEP 1. Pairs GLP-1 with resistance training and 1g protein/lb.
Conservative 1/10th dose approach: 0.025-0.05mg weekly. "Dose up to appetite control, not suppression."
Tirzepatide
The most powerful weight loss peptide available. Tirzepatide targets both GIP and GLP-1 receptors, producing up to 22.5% body weight loss in clinical trials — more than any single-agonist peptide.
- FDA-approved (Mounjaro/Zepbound)
- Superior weight loss vs semaglutide in head-to-head trials
- Dual mechanism (GIP + GLP-1)
- Once-weekly dosing
- GI side effects during titration (nausea, diarrhea)
- Expensive
- Weight regain after discontinuation
Semaglutide
The most well-known GLP-1 agonist (Ozempic/Wegovy). Proven 15-17% body weight loss in trials with the most extensive long-term safety data of any weight loss peptide.
- FDA-approved with extensive safety data
- Proven cardiovascular benefits
- Once-weekly dosing
- Most accessible GLP-1 option
- Less effective than tirzepatide in trials
- GI side effects common during titration
- Weight regain after stopping
Orforglipron
The first oral non-peptide GLP-1 agonist (brand name Foundayo). FDA-approved in April 2026. Unlike every other GLP-1 drug, it's a small-molecule pill you take once daily with no food or water restrictions. The ATTAIN-1 trial showed 12.4% body weight loss, and it beat oral semaglutide head-to-head in the ACHIEVE-3 trial.
- FDA-approved — no injections needed
- No food, water, or fasting restrictions (unlike oral semaglutide)
- Take it any time of day
- Self-pay price of $149/month
- Less weight loss than injectable tirzepatide or semaglutide
- Higher GI side effect discontinuation rate than injectables
- Requires daily dosing (not weekly)
Retatrutide
The first triple-agonist (GLP-1 + GIP + glucagon). Phase 2 trials showed up to 24% body weight loss — the highest of any peptide ever studied. The glucagon component also reduces liver fat.
- Highest weight loss in any trial (24%)
- Triple mechanism attacks fat from 3 angles
- Reduces liver fat significantly
- Once-weekly dosing
- Still investigational — not yet FDA-approved
- Limited long-term safety data
- GI side effects during titration
AOD-9604
A targeted fat-burning fragment of HGH (amino acids 177-191). Unlike GLP-1 agonists, it directly stimulates lipolysis without affecting appetite, blood sugar, or growth. A different mechanism entirely — it can be paired with GLP-1 drugs for combined fat loss.
- Directly targets fat metabolism
- No effect on blood sugar or insulin
- GRAS safety status
- Can be combined with GLP-1 agonists
- Much weaker weight loss than GLP-1 agonists
- Requires daily dosing on empty stomach
- Phase 2 data only — limited clinical evidence
Head-to-Head Comparisons
See how these ranked peptides compare side by side.
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How We Ranked These
Ranked by clinical trial weight loss data, FDA approval status, mechanism breadth, and real-world accessibility. FDA-approved options rank above investigational ones. GLP-1 agonists lead because they have the strongest evidence base.
Beginner Recommendation
Start with Semaglutide for proven, accessible weight loss. Prefer Orforglipron if you want an oral option with no needles. Tirzepatide for maximum results.
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