Retatrutide

Be clear about what is known and what is not. Retatrutide (LY3437943) is an investigational once-weekly injectable agonist at the GIP, GLP-1, and glucagon receptors. Its weight and metabolic data are strong for a phase 2 agent: a 338-person double-blind randomized trial reported a least-squares mean body weight change of -24.2% at 48 weeks in the highest trial arm versus -2.1% for placebo (Jastreboff 2023, PMID: 37366315), and several independent network meta-analyses rank it at or near the top of the class for weight reduction (Sinha 2025, PMID: 40685589; Abulehia 2026, PMID: 41787737). What is genuinely thin is everything this page exists to answer. There are, as of this update, no randomized trials testing any dietary supplement, protein target, or micronutrient protocol specifically in people taking retatrutide. Every nutrition and supplement recommendation below is extrapolated from semaglutide, liraglutide, and tirzepatide research, and one review of the surgical and nutritional literature states plainly that direct trial evidence for supplementation strategies in this population is lacking (Elawa 2026, PMID: 42155603). Retatrutide is also not an approved medicine in any market we are aware of, which means the identity, purity, and concentration of anything sold under that name outside a registered clinical trial or a licensed prescriber are unverified. If you are on it, your prescriber owns the dose and the titration. This page covers only what may reasonably sit alongside it: protein and resistance training to help maintain lean mass, monitoring for the micronutrient gaps documented across the incretin class, and the timing and interaction issues created by delayed gastric emptying.