Research Review
Best Peptides for Fat Loss UK 2026 — Ranked by Clinical Evidence
This research review ranks the most studied peptides in the context of fat loss and metabolic research — based on published clinical and preclinical evidence. All compounds listed are available from Alluvi Healthcare for in vitro laboratory research purposes only.
Mechanism: Triple agonist — GLP-1, GIP, Glucagon receptors simultaneously.
Retatrutide achieved 22.5% average body weight reduction at 48 weeks in Phase 2 trials — the highest figure recorded for any GLP-1 class compound. The glucagon component increases resting energy expenditure, providing a mechanism tirzepatide and semaglutide lack. For fat loss research, retatrutide represents the most comprehensive multi-pathway target available.
Research grade available from: Alluvi Retatrutide 40mg Pen — £195
Mechanism: Dual agonist — GLP-1 and GIP receptors.
Tirzepatide (Mounjaro's active molecule) demonstrated ~22% weight reduction in SURMOUNT trials — comparable to retatrutide at the highest doses. The GIP component distinguishes it from semaglutide, improving tolerability and adipose tissue effects. A well-characterised compound with extensive clinical data making it ideal for mechanistic comparison studies.
Research grade available from: Alluvi Tirzepatide 40mg — £115
Mechanism: Single agonist — GLP-1 receptor only.
Semaglutide (Ozempic/Wegovy) achieved ~15% weight reduction in STEP trials. As the most extensively studied GLP-1 agonist with the largest clinical dataset, it remains the standard benchmark compound for GLP-1 mechanism research. Not currently available from Alluvi Healthcare — listed for comparative context.
Mechanism: Body Protection Compound — multi-pathway tissue repair and metabolic regulation.
BPC-157 has shown interesting preclinical data in metabolic regulation research contexts, including effects on ghrelin pathways and energy homeostasis. While not a primary fat loss compound, it is often used alongside GLP-1 research protocols. Available from Alluvi Healthcare as a combined BPC-157 & TB-500 40mg blend.
Research grade available from: Alluvi BPC-157 & TB-500 40mg — £109.99
Mechanism: Copper peptide — cellular regeneration, collagen synthesis, anti-inflammatory.
GHK-Cu is primarily researched in skin, hair and cellular repair contexts rather than direct fat loss. However, its anti-inflammatory properties make it relevant to research investigating metabolic inflammation pathways. Available in Alluvi's Glow blend (BPC-157 10mg / TB-500 10mg / GHK-Cu 50mg).
Research grade available from: Alluvi Glow GHK-Cu 70mg — £75
| Peptide | Mechanism | Peak Efficacy (trials) | UK Research Price |
|---|---|---|---|
| Retatrutide | GLP-1/GIP/GCG triple | ~22.5% (48wk) | From £195 |
| Tirzepatide | GLP-1/GIP dual | ~22% (72wk) | From £115 |
| Semaglutide | GLP-1 single | ~15% (68wk) | Not stocked |
| BPC-157 | Multi-pathway repair | Preclinical only | From £109.99 |
| GHK-Cu | Cellular repair | Preclinical only | From £75 |
Alluvi Healthcare supplies independently verified research peptides with full COA, cold chain delivery and UK-based support. Batch AR0763RT4 — 99.38% purity.