Best peptides for muscle growth and fat loss: the recomp list, ranked by evidence instead of hype

“Recomp” is the gym word for losing fat and gaining muscle at the same time, and peptides get sold into that goal as if one vial could do both. This list takes the claim apart. Instead of ranking compounds by how often they come up in forums, it ranks them on two separate scores: how much human evidence exists that each one reduces fat, and how much exists that it adds muscle. Those two scores rarely line up. The compounds with the strongest fat-loss trials tend to cost some lean mass, and the ones sold as muscle builders were mostly measured as hormone changes. Every research statement links to its primary source, and the community section is kept apart from the evidence.

What are the best peptides for muscle growth and fat loss?

If “best” means the most human evidence for both halves of a recomp, tesamorelin ranks first among the growth hormone peptides, though its trials were in patients, not lifters. In adults with HIV and excess belly fat it cut visceral fat by 15.2% while placebo rose 5.0% (Falutz et al., 2007), and lean body mass rose 1.3 kg and 1.2 kg in the two pivotal trials (Egrifta WR label). The GLP-1 drugs and retatrutide remove far more fat, but lean mass falls too. Everything else on this list has either hormone-only human data or mouse data.

How this list ranks peptides for fat loss and muscle gain

Each compound gets an evidence level in plain words and two findings: what happened to fat, and what happened to lean or muscle tissue, in the best human study we could find. Three rules shape the ranking:

1. Human data beats animal data. A mouse that lost weight in 11 days is a reason to study a compound, not evidence that it works in a person.
2. Lean mass is not muscle. DXA scans report “lean body mass” or “fat-free mass,” which counts muscle plus water, organs and other non-fat tissue. A growth hormone drug that causes fluid retention can move that number without adding contractile tissue.
3. Nobody here was a trained lifter. We found no randomized trial of any compound on this list in healthy, resistance-trained adults. Every ranking below is borrowed from patients, older adults or people with obesity.

The ranking, compound by compound

Ordered by how close the human evidence gets to a real recomp: fat down and lean tissue up, in people.

1. Tesamorelin: the strongest human recomp signal among GH peptides

Tesamorelin’s evidence level is an approved drug studied in its labeled population. It is a synthetic version of growth hormone-releasing hormone (GHRH), approved as Egrifta to reduce excess abdominal fat in adults with HIV and lipodystrophy. The label is blunt about one thing lifters miss: it “is not indicated for weight loss management as it has a weight neutral effect” (Egrifta WR label). That weight-neutral profile is exactly why it shows up in recomp talk, because the scale stays flat while the composition shifts.

• Fat. In a 26-week randomized trial of 412 adults with HIV, daily tesamorelin cut visceral fat 15.2% while placebo rose 5.0%, and triglycerides fell (Falutz et al., 2007). Outside HIV, a 12-month trial in 60 abdominally obese adults with reduced GH secretion also cut visceral fat, with no significant effect on the fat under the skin (Makimura et al., 2012).
• Lean mass. The label reports lean body mass gains of 1.3 kg and 1.2 kg against small falls on placebo (Egrifta WR label). A 2026 meta-analysis of five randomized trials pooled the lean mass gain at 1.42 kg, with trunk fat down 1.18 kg, and found no significant change in subcutaneous fat or BMI (Badran et al., 2026).

Read the fine print before calling that a recomp. The fat it reliably removes is visceral, the deep belly fat around the organs, not the fat a mirror shows. Strength was never a trial endpoint. Our page on whether tesamorelin builds muscle walks through what the scans can and cannot tell you.

2. GLP-1 drugs and retatrutide: the most fat loss, at a lean-mass cost

The GLP-1 class has the evidence level of large randomized trials (semaglutide, tirzepatide) plus an investigational drug with published phase 2 data (retatrutide). For pure fat loss nothing else on this list comes close. In the phase 2 retatrutide trial, 338 adults with obesity lost an average of 24.2% of body weight at 48 weeks on the 12 mg dose, against 2.1% on placebo (Jastreboff et al., 2023).

For a recomp, though, the direction of lean mass matters, and it goes down. In the STEP 1 DXA substudy of semaglutide 2.4 mg, total fat mass fell about 19.3% and lean body mass about 9.7%; in SURMOUNT-1, tirzepatide cut fat mass about 33.9% and lean mass about 10.9%, with roughly 75% of the weight lost coming from fat (De Girolamo et al., 2026 review). A Lilly-funded body-composition substudy of retatrutide in people with type 2 diabetes found total fat mass fell 26.1% on the pooled 8 mg groups and 23.2% on 12 mg at 36 weeks, against 4.5% on placebo, and its authors reported the share of weight lost as lean mass was similar to other obesity treatments (Coskun et al., 2025).

So these drugs improve the ratio of lean to fat because fat falls faster, not because muscle is built. That is why “peptides for weight loss and muscle gain” is mostly a question about protecting muscle while on a GLP-1, which our guide to preserving muscle on a GLP-1 covers in detail, from protein targets to rate of loss. Our sister site’s guide to peptides for weight loss ranks the fat-loss side of this list on its own.

3. MK-677: lean mass up, fat not down

MK-677 (ibutamoren) has the evidence level of randomized trials in older and obese adults, and it is an oral ghrelin mimetic rather than a peptide. In a two-year trial of 65 healthy adults aged 60 to 81, fat-free mass rose 1.1 kg against a 0.5 kg fall on placebo, but there was no significant difference in visceral or total fat, limb fat rose more than on placebo, and body weight rose 2.7 kg; the authors reported that the extra fat-free mass “did not result in changes in strength or function” (Nass et al., 2008). An eight-week trial in 24 obese men found the same split: fat-free mass increased, total and visceral fat did not change (Svensson et al., 1998). That is half a recomp at best, with the scale moving up.

4. CJC-1295 and ipamorelin: measured as hormones, not body composition

The most popular GH stack has the thinnest relevant data: the human trials we found for CJC-1295 are small pharmacology studies. In two placebo-controlled trials in healthy adults, a single CJC-1295 injection raised GH 2- to 10-fold for six days or more and IGF-1 1.5- to 3-fold for 9 to 11 days; the main outcome measures were GH and IGF-1 levels (Teichman et al., 2006). Neither fat mass nor muscle was the question. Any recomp claim for this stack rests on the assumption that more GH means a better body composition, which the growth hormone section below tests directly. Our guide to peptides for muscle growth covers this stack’s evidence in more depth.

5. MOTS-c: fat and fitness results in mice

MOTS-c’s evidence level is mostly animal and cell studies. It is a 16-amino-acid peptide encoded in mitochondrial DNA; in mice, treatment “prevented age-dependent and high-fat-diet-induced insulin resistance, as well as diet-induced obesity,” with skeletal muscle as its apparent main target (Lee et al., 2015). A later study found it improved physical performance in young, middle-aged and old mice, while the human data in the same paper showed that exercise raises the body’s own MOTS-c in muscle and blood (Reynolds et al., 2021). That last finding is about training raising MOTS-c, not about MOTS-c replacing training. The Treatment Report’s MOTS-c overview covers the full record. For athletes, the bigger issue is that MOTS-c is on the WADA Prohibited List, covered in is MOTS-c banned?.

6. 5-Amino-1MQ: mouse fat loss, mouse grip strength

5-Amino-1MQ’s evidence level is cell and mouse studies only, and it is a small molecule, not a peptide. It blocks an enzyme called NNMT; in cultured fat cells that raised NAD+ and suppressed fat building, and in diet-induced obese mice it reduced body weight and white fat mass without changing food intake (Neelakantan et al., 2018). On the muscle side, aged sedentary mice given an NNMT inhibitor showed about 40% greater grip strength than sedentary controls, and the effect added to exercise (Dimet-Wiley et al., 2024). That paper’s authors disclose that the senior author founded Ridgeline Therapeutics, which develops NNMT inhibitors, and that two co-authors work there. The Treatment Report’s 5-Amino-1MQ overview explains the chemistry.

Recomp peptides side by side

The table ranks each compound on its best human evidence. “Lean mass” means a body-composition scan result, which is not the same as measured muscle size or strength.

Recomp compounds: what the best human or animal studies measured for fat and for lean tissue. Sources are linked in the sections above.

Attribute	Tesamorelin	GLP-1 drugs and retatrutide	MK-677	CJC-1295 + ipamorelin	MOTS-c	5-Amino-1MQ
What it is	GHRH analog, approved drug (Egrifta)	Gut-hormone peptide drugs; retatrutide investigational	Oral ghrelin mimetic, not a peptide	GHRH analog plus ghrelin-mimetic peptide	Mitochondrial-derived peptide	Small-molecule NNMT inhibitor, not a peptide
Evidence level	Approved drug, labeled use in HIV lipodystrophy	Large randomized trials; retatrutide phase 2 published	Randomized trials in older and obese adults	Small human pharmacology trials (CJC-1295)	Mostly animal and cell studies	Cell and mouse studies only
Fat-loss finding	Visceral fat down about 15%; weight neutral	Largest: fat mass down about 19% to 34% in DXA substudies	No significant change in total or visceral fat	Not measured	Prevented diet-induced obesity in mice	Lower weight and fat mass in obese mice
Lean or muscle finding	Lean mass up about 1.2 to 1.4 kg	Lean mass down about 10%	Fat-free mass up 1.1 kg, no strength change	Not measured	Better physical performance in mice	Higher grip strength in aged mice
Trained lifters studied?	No	No	No	No	No	No
Notable risks from the data	Joint pain, swelling, glucose intolerance	Mainly gastrointestinal effects; heart rate rise	Appetite, edema, higher glucose	Short-term data only	No human treatment data	No human data

What is the most powerful peptide for fat loss?

By the size of the effect in human trials, the gut-hormone peptide drugs are the most powerful, and retatrutide posted an average loss of 24.2% of body weight at 48 weeks on the top dose in its published phase 2 trial (Jastreboff et al., 2023). Among growth hormone peptides, tesamorelin is the only one with large trials showing fat loss, and its effect is targeted at visceral fat rather than body weight (Falutz et al., 2007). “Most powerful” for weight is not the same as best for a recomp, because the biggest fat losses came with lean-mass losses.

Which peptides are best for muscle growth?

No peptide has been shown in a controlled trial to build muscle in healthy lifters, so “best” can only mean the most relevant human data. On that measure tesamorelin leads, with a lean-mass gain of roughly 1.2 to 1.4 kg in patient trials (Badran et al., 2026), followed by MK-677, whose 1.1 kg fat-free mass gain came without any change in strength (Nass et al., 2008). The CJC-1295 trials measured only hormone levels. Our guide to peptides for muscle growth ranks the muscle side alone.

Do peptides really work for muscle building?

Not in any way that has been shown in people who train. The clearest test of the idea comes from growth hormone itself, the end point every GH peptide is trying to raise: a systematic review of 27 study samples in young, lean, fit adults found GH raised lean body mass by 2.1 kg, but “strength and exercise capacity did not seem to improve,” and soft tissue swelling and fatigue were more common (Liu et al., 2008). If injected GH did not reliably make fit people stronger, a peptide that nudges your own GH upward should be expected to do less.

Can a peptide build muscle and burn fat at the same time?

Growth hormone is the one route with human data pointing both ways at once, and even there the muscle half is a scan reading rather than strength. A meta-analysis of 11 placebo-controlled trials in healthy young adults found GH increased lean body mass and decreased fat mass, but did not improve muscle strength or aerobic capacity (Hermansen et al., 2017). Tesamorelin shows a similar two-way shift in patients: visceral fat down, lean mass up, weight unchanged (Egrifta WR label). That is a body-composition shift on paper, not proof of new muscle, and part of the lean gain may be water.

Peptides for weight loss and muscle gain: why lifters stack them

Stacking is the community’s attempt to get both halves of a recomp from different compounds, and no stack on this page has been tested as a combination. The common logic pairs a fat-loss drug with a GH-axis compound in the hope of offsetting the lean-mass loss seen with the GLP-1 class (De Girolamo et al., 2026 review). Pre-mixed blends such as tesamorelin with ipamorelin follow the same idea of combining two GH-axis compounds. We found no published human trial of a GLP-1 plus GH peptide combination, or of the tesamorelin and ipamorelin blend, for body composition, so every stack claim rests on the separate parts. Stacking also makes it impossible to tell which compound caused a result or a side effect. For a side-by-side of the two GH peptides most often paired, see our comparison of tesamorelin and ipamorelin.

Side effects and who should be cautious

The side effects follow the mechanism. Raising growth hormone brings fluid and joint effects and pressure on blood sugar: the tesamorelin label lists joint pain, swelling in the limbs and muscle pain among its most common reactions, and warns that glucose intolerance or diabetes may develop (Egrifta WR label). In the first phase 3 trial, more tesamorelin patients than placebo patients withdrew because of an adverse event (Falutz et al., 2007). MK-677 raised fasting glucose by about 5 mg/dL, lowered insulin sensitivity and increased appetite (Nass et al., 2008). Our page on tesamorelin side effects covers that compound in detail.

The fat-loss drugs bring a different profile. In the retatrutide phase 2 trial, the most common adverse events were gastrointestinal, dose-related and mostly mild to moderate, and heart rate rose with dose before declining after 24 weeks (Jastreboff et al., 2023). For MOTS-c and 5-Amino-1MQ there is no human side-effect data to report. People with diabetes or prediabetes, anyone with a history of cancer, and competitive athletes subject to drug testing have the most reason to talk to a clinician first.

What does a peptide recomp cost?

A recomp is a months-long project, so the cost compounds with time while the evidence does not get any stronger. Tesamorelin’s own trial data show the effect does not outlast the drug: in the extension phase, patients switched to placebo regained visceral fat and lost lean body mass (Egrifta WR label). Any honest budget therefore includes the question of what happens when you stop. The Treatment Report’s peptide and GLP-1 therapy cost explainer breaks down what drives the price.

What the community is saying about peptides for recomp

On social media, recomp peptides are discussed as stacks rather than single compounds, with the payoff described in terms of recovery and energy more than measured fat or muscle. Our Community Insights summary for CJC-1295 on this site analyzed 17 public posts on X from July 13 to 19, 2026, and our network summary for MOTS-c analyzed 19 public posts on X from July 16 to 19, 2026. We have not yet built a community dataset for tesamorelin or 5-Amino-1MQ, so we do not characterize user reports for those. These are anecdotes, not evidence.

• The GH stack for body composition. Posters repeatedly name CJC-1295 plus ipamorelin as the go-to combination aimed at recovery and body composition, though most discussion is promotional rather than detailed about results.
• Physique changes inside big stacks. Several people reporting physique transformations were also running many other compounds at once, which makes any single peptide’s effect impossible to isolate.
• MOTS-c as a training add-on. Posters describe fitting MOTS-c into wider routines with NAD+, GLP peptides, pre-workout, fasting and cardio, and many frame it as an energy peptide; some report noticeable improvements.
• Skepticism. Others call MOTS-c part of a hype cycle in which people chase each new peptide, while one poster who expected to dismiss it revised his view after a month of daily use.
• Side-effect worries. CJC-1295 posters report flushing, wrecked sleep and bloodshot eyes, and some warn that the long-acting DAC version’s continuous GH elevation may bring insulin resistance.

Set against the research, the community picture runs ahead of the data. The insulin worry lines up with what the trials recorded for GH-axis compounds, glucose intolerance on the tesamorelin label and lower insulin sensitivity on MK-677. The recomp results posters describe are the part no controlled trial has measured in lifters.

The bottom line for recomp

Ranked honestly, the list splits in two. For fat loss, the GLP-1 drugs and retatrutide are in a different league, but lean mass falls with the fat. For a fat-down, lean-up shift, tesamorelin has the most human data of any GH peptide, in HIV patients and obese adults with low GH, with visceral fat down about 15% and lean mass up around a kilogram, and the effect fades after stopping. MK-677 adds lean mass without removing fat, and CJC-1295, ipamorelin, MOTS-c and 5-Amino-1MQ have no human recomp data at all. Before weighing any of them, ask what species was studied, what outcome was measured and for how long, and talk it through with a clinician who knows your labs.

Status: Tesamorelin is FDA-approved only as Egrifta, for HIV-related abdominal fat; other uses are off-label. CJC-1295, ipamorelin and 5-Amino-1MQ: not FDA-approved; sold by some telehealth providers as a compounded prescription. MOTS-c: not FDA-approved; sold by some telehealth providers as a compounded prescription, and an FDA advisory committee reportedly voted in July 2026 to recommend allowing pharmacies to compound it; nothing has changed yet. Retatrutide: investigational; not FDA-approved. Lilly plans to submit it for approval in Q1 2027. What these status terms mean.

Educational information only, not medical advice. Every efficacy and safety statement on this page is sourced to the peer-reviewed literature or the FDA drug label linked above; the community summary reflects public posts on X analyzed in July 2026. Updated October 12, 2026. This page is drafted with AI assistance and fact-checked against the cited primary sources before publication.