Metabolic & Cardiometabolic
over-the-counter supplements does not induce simultaneous muscle gain and fat loss
In plain terms: Is there no over-the-counter supplement that both builds muscle and burns fat?
Essentially true — CLA, HMB, carnitine and green-tea extracts do neither meaningfully; the one partial exception is creatine, which nudges lean mass up and fat slightly down, but the fat effect is tiny and a byproduct of training, not real simultaneous fat-burning.
📅 Last reviewed: 2026-07-14 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
What the evidence shows
No over-the-counter supplement does both jobs. Pooled trials find conjugated linoleic acid producing only a trivial fat reduction and no muscle gain, and L-carnitine across 37 trials giving modest weight loss with no muscle effect. Creatine is the partial exception, and even there the body-fat change is about half a percentage point.
The evidence (10)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Whigham LD, Watras AC, Schoeller DA 2007 · Am J Clin Nutr | meta-analysis | supports | moderate | Meta-analysis found CLA produces only a trivial fat-mass reduction in humans and no meaningful muscle-building effect. |
| Sung HK, Kim J, Oh D, Eun SW, Tatsuzaki J, Shin SM, Jeong SH 2025 · Frontiers in nutrition | RCT | supports | moderate | 12-week RCT of Kaempferia parviflora extract (SIRTMAX) in 83 overweight Korean adults found significant reductions in body fat mass, body fat percentage, and body weight versus control, with no significant change reported in lean body mass |
| Talenezhad N, Mohammadi M, Ramezani-Jolfaie N, Mozaffari-Khosravi H, Salehi-Abargouei A 2020 · Clin Nutr ESPEN | meta-analysis | supports | moderate | Meta-analysis of 37 RCTs found L-carnitine produced modest weight loss only, with no muscle-building effect. |
| Chen YC, Huang YC, Cheng YJ, Man JWK, Hsieh RH, Hsu SY, Chen YH 2025 · ACS pharmacology & translational science | observational | contradicts | low | In a Taiwanese adolescent cohort (n=1641), higher glycyrrhizin consumption correlated with lower body fat and higher fat-free mass, especially in nonobese individuals; parallel mouse/preadipocyte experiments showed reduced adiposity and inc |
| Forbes SC, Candow DG, Krentz JR, Roberts MD, Young KC 2019 · J Funct Morphol Kinesiol | meta-analysis | mixed | moderate | Meta-analysis found creatine plus resistance training reduced body-fat percentage by only ~0.55%, a marginal effect alongside lean gains. |
| Lin Z, Zhao Y, Chen Q 2021 · Eur Geriatr Med | meta-analysis | supports | moderate | Meta-analysis found HMB effects on lean mass in older adults are small and controversial, not a reliable muscle-builder plus fat-burner. |
| Desai I, Wewege MA, Jones MD, Clifford BK, Pandit A, Kaakoush NO, Simar D, Hagstrom AD 2024 · J Strength Cond Res | meta-analysis | mixed | moderate | Meta-analysis found creatine plus training increased lean mass ~1.1 kg and reduced fat ~0.7 kg, but the fat change is small and secondary to training, not true simultaneous fat-burning. |
| Esmaeilnejad M, Rasaei N, Goudarzi K, Behrouz Dehkordi Z, Dolatshahi S, Salehi Omran H, Amirani N, Ashtary-Larky D, Shimi G, Asbaghi O 2024 · Br J Nutr | meta-analysis | supports | high | Meta-analysis of 14 RCTs found CLA reduced body weight by under 1 kg with no evidence of simultaneous muscle gain. |
| García-Alonso A, Sánchez-González JL, Navarro-López V, Méndez-Sánchez R, Polo-Ferrero L 2025 · Nutrients | meta-analysis | supports | moderate | Meta-analysis found HMB added to resistance training gave unclear/limited additional body-composition benefit over training alone. |
| Vázquez Cisneros LC, López-Uriarte P, López-Espinoza A, Navarro Meza M, Espinoza-Gallardo AC, Guzmán Aburto MB 2017 · Nutr Hosp | meta-analysis | supports | moderate | Systematic review found green tea/EGCG yields modest fat/weight reduction only, with no anabolic muscle effect. |
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.