While collagen supplements are widely praised for their potential benefits in joint health, recovery, and skin quality, recent research suggests that the reality may not match the hype that often surrounds these products. Dr. Layne Norton, a Ph.D. in Nutritional Sciences, expresses skepticism about the value of collagen supplementation.
Last updated on December 19th, 2025
Collagen, as the most abundant protein in the human body, plays a crucial role in the formation of skin, bones, tendons, ligaments, and cartilage. While there are various types of collagen, types I, II, and III are particularly relevant to fitness and joint/skin health.
Dr. Layne Norton questions the legitimacy of collagen supplementation, stating that it appears to be potentially misleading.
—Dr. Layne Norton
Understanding the Functions of Collagen
Collagen provides structural support by creating a network that sustains connective tissues, resists stretching, and preserves shape. It also contributes to joint health by cushioning joints and minimizing impact and friction during movement. Additionally, collagen aids in skin and tissue repair, enhancing skin elasticity and wound healing processes. Moreover, collagen supplies essential amino acids like glycine, proline, and hydroxyproline, which are utilized by the body to produce collagen.
- Type I: Found in skin, tendons, and bones
- Type II: Present in cartilage
- Type III: Found in skin and blood vessels
There are four primary ways in which collagen functions within 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.
Exploring the Claims
In an effort to debunk marketing myths, a study published in 2023 by Medicine & Science in Sports & Exercise investigated the impact of collagen supplementation on muscle connective tissue protein synthesis post-exercise.
The study results indicated that ingesting collagen during recovery did not lead to an increase in connective tissue protein synthesis, suggesting that it may not enhance muscle and tendon repair as some proponents claim. (1)
If muscle and connective tissue do not experience significant benefits, what about skin health? Recent evidence suggests that collagen may not effectively improve skin hydration, elasticity, or wrinkles. A meta-analysis from 2025, involving 23 randomized controlled trials with 1,474 participants, revealed positive outcomes only in studies funded by pharmaceutical companies. Conversely, studies not backed by pharmaceutical funding did not report substantial benefits. (2)
Excluding outlier studies, collagen supplements showed no significant improvements in wrinkles, hydration, or elasticity.
—Dr. Layne Norton
Collagen vs Whey Protein
Opting for whey protein over collagen may be a more advantageous choice for enhancing strength, vitality, and muscle development. Head-to-head comparisons consistently show whey protein outperforming collagen in terms of muscle growth. (3)
Studies have indicated no significant disparities between whey protein and collagen in stimulating connective tissue synthesis, making collagen the less favorable option for individuals seeking muscle growth or recovery benefits. (4) (5)
Dr. Norton emphasizes, “Collagen possesses one of the poorest amino acid profiles among available protein sources. It notably lacks essential amino acids, especially branch chain amino acids and leucine, which are essential for stimulating muscle protein synthesis.”
Concluding Remarks
While many individuals seek an extra edge in their training regimen, high-quality research suggests that collagen’s impact on muscle and connective tissue may be inconsistent. Its actual influence on muscle growth, recovery, and skin health seems to be limited, leading to ongoing debates regarding its effectiveness.
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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