Despite its reputation, collagen supplementation leaves plenty to be desired.
Last updated on December 19th, 2025
Collagen is a popular fitness supplement, touted for its benefits for joint health, recovery, and skin. But is it all hype? The most recent research suggests collagen may not live up to the claims that permeate the fitness world. Dr. Layne Norton, Ph.D. in Nutritional Sciences, doubts collagen’s value.
Collagen supplementation looks like a scam. I am skeptical.
—Dr. Layne Norton
How Collagen Works
Collagen is the most abundant protein in the human body, helping make up the skin, bones, tendons, ligaments, and cartilage. There are at least 16 types, but types I, II, and III are closely tied to fitness and joint/skin health.
- Type I: Skin, tendons, bones
- Type II: Cartilage
- Type III: Skin, blood vessels
There are four main ways collagen works in the body:
- Structural Support: Collagen fibers form a network that supports connective tissues, resists stretching, and maintains shape.
- Joint Health: Collagen, part of cartilage, cushions joints from impact and friction during movement.
- Skin & Tissue Repair: Collagen contributes to skin elasticity and wound healing.
- Amino Acid Supply: Collagen provides amino acids like glycine, proline, and hydroxyproline that the body can use to make collagen.
Editor’s note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. Talking to your doctor before beginning a new fitness, nutritional, and/or supplement routine is always a good idea.
Unpacking the Hype
To separate fact from marketing, a 2023 randomized controlled trial from Medicine & Science in Sports & Exercise examined how collagen supplementation affects muscle connective tissue protein synthesis after exercise.
The findings showed that collagen ingestion during recovery did not increase connective tissue protein synthesis, suggesting that it may not enhance muscle and tendon repair the way some supplements claim. (1)
If muscle and connective tissue don’t benefit, what about skin? New evidence indicates collagen might not help skin hydration, elasticity, or wrinkles. A 2025 meta-analysis of 23 randomized controlled trials, including 1,474 participants, found improvements only in pharma-funded studies. In contrast, research not funded by pharmaceutical companies reported no significant benefits. (2)
Excluding outlier studies, collagen supplements showed no significant improvements in wrinkles, hydration, or elasticity.
—Dr. Layne Norton
Collagen vs Whey Protein
Swapping collagen for whey protein might be the right move for strength, vitality, and muscle building. Whey protein consistently outperforms collagen in head-to-head comparisons for hypertrophy. (3)
Research has shown no significant differences between whey and collagen for stimulating connective tissue synthesis, making collagen the inferior option for those seeking muscle growth or recovery benefits. (4) (5)
“Collagen literally has the worst amino acid profile of any protein source on the market,” Dr. Norton asserted. “It is absurdly low in essential amino acids, specifically the branch chain amino acids and leucine, which stimulate muscle protein synthesis.”
Final Thoughts
Everyone wants an edge in training, but high-quality research shows collagen’s effects on muscle and connective tissue are inconsistent. Its real-world impact on muscle growth, recovery, and skin health appears limited, leaving its effectiveness debatable.
More In Research
References
- Aussieker T, Hilkens L, Holwerda AM, Fuchs CJ, Houben LHP, Senden JM, VAN Dijk JW, Snijders T, VAN Loon LJC. Collagen Protein Ingestion during Recovery from Exercise Does Not Increase Muscle Connective Protein Synthesis Rates. Med Sci Sports Exerc. 2023 Oct 1;55(10):1792-1802. doi: 10.1249/MSS.0000000000003214. Epub 2023 May 19. PMID: 37202878; PMCID: PMC10487367. https://pubmed.ncbi.nlm.nih.gov/37202878/
- Myung SK, Park Y. Effects of Collagen Supplements on Skin Aging: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Am J Med. 2025 Sep;138(9):1264-1277. doi: 10.1016/j.amjmed.2025.04.034. Epub 2025 May 3. PMID: 40324552. https://pubmed.ncbi.nlm.nih.gov/40324552/
- Jacinto JL, Nunes JP, Gorissen SHM, Capel DMG, Bernardes AG, Ribeiro AS, Cyrino ES, Phillips SM, Aguiar AF. Whey Protein Supplementation Is Superior to Leucine-Matched Collagen Peptides to Increase Muscle Thickness During a 10-Week Resistance Training Program in Untrained Young Adults. Int J Sport Nutr Exerc Metab. 2022 May 1;32(3):133-143. doi: 10.1123/ijsnem.2021-0265. Epub 2022 Jan 17. PMID: 35042187. https://pubmed.ncbi.nlm.nih.gov/35042187/
- Kirmse M, Lottmann TM, Volk NR, DE Marées M, Holwerda AM, VAN Loon LJC, Platen P. Collagen Peptide Supplementation during Training Does Not Further Increase Connective Tissue Protein Synthesis Rates. Med Sci Sports Exerc. 2024 Dec 1;56(12):2296-2304. doi: 10.1249/MSS.0000000000003519. Epub 2024 Jul 31. PMID: 39086044. https://pubmed.ncbi.nlm.nih.gov/39086044/
- Oikawa SY, Kamal MJ, Webb EK, McGlory C, Baker SK, Phillips SM. Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: a randomized controlled trial. Am J Clin Nutr. 2020 Mar 1;111(3):708-718. doi: 10.1093/ajcn/nqz332. Erratum in: Am J Clin Nutr. 2020 Dec 10;112(6):1656. doi: 10.1093/ajcn/nqaa275. PMID: 31919527; PMCID: PMC7049534. https://pubmed.ncbi.nlm.nih.gov/31919527/
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