Collagen: Youth Powder Or Expensive Placebo?
- Lidi Garcia
- Jul 11
- 5 min read
A new meta-analysis of 23 studies on collagen supplements for skin aging revealed that while studies generally indicate improvements in hydration, elasticity, and wrinkles, these effects disappear when only independent, high-quality studies are considered. In other words, the benefits only appear in industry-funded or low-quality research. Thus, there is no reliable clinical evidence that collagen supplements prevent or treat skin aging. This highlights a broader problem: the influence of funding bias in the supplement industry, whose promises often outweigh the evidence.
The collagen supplement market has been growing rapidly, driven by the promise of rejuvenating skin, strengthening joints, and promoting a more youthful appearance. Celebrities, influencers, and beauty companies promote the supposed benefits of this protein daily, generating a billion-dollar market.
In the United States alone, consumers spent more than $4 billion on collagen, and continued growth is expected. But a robust new scientific analysis has just cast serious doubt on the true effectiveness of these products, especially when it comes to skin aging.
Collagen is an essential protein found in the body's connective tissues, such as skin, bones, tendons, and ligaments. It represents over 90% of skin's composition and is crucial for its firmness and elasticity. As we age, the body's natural collagen production decreases by about 1% to 1.5% per year, contributing to the appearance of wrinkles, sagging, and dry skin.
The logic behind supplementation would be simple: by replenishing collagen, we would improve skin quality. But the biological reality is much more complex.
There are at least 28 identified types of collagen, but the most relevant to human health are types I, II, and III. Type I is the most abundant in the body, responsible for providing strength to skin, bones, tendons, and ligaments. Type II is found primarily in cartilage and is essential for joint health. Type III is common in more flexible tissues, such as blood vessels and young skin, working in conjunction with type I. Supplements often contain hydrolyzed collagen (or collagen peptides), which combine these types into versions that are more easily absorbed by the body.
When we ingest collagen, whether in powder, capsule, gummy, or drink form, it is broken down in the digestive system into small fragments, called amino acids. The body then utilizes these fragments as needed, and may or may not use them to form collagen.
The big challenge is ensuring that these amino acids, once absorbed, are actually used to rebuild the skin and not other tissues. Scientists still can't clearly explain how ingested collagen could specifically target the dermis (the deepest layer of the skin). This biological gap was already a concern, and now new evidence raises even more doubts about the true benefits of supplementation.
A new meta-analysis published in 2025 analyzed 23 randomized controlled trials (RCTs) with more than 1,400 participants, all evaluating the effects of collagen supplements on skin, particularly in terms of hydration, elasticity, and wrinkles.
At first, the results seemed promising: when all the studies were pooled, the supplements showed modest benefits. However, the authors decided to investigate further, dividing the studies according to methodological quality and funding source. And that's when a worrying pattern emerged.
Studies funded by companies in the industry, that is, those with a direct interest in selling the product, consistently reported significant benefits. Independent studies, unaffiliated with the industry, found no measurable effect.
The same was true when considering the quality of the studies: high-quality studies showed no real benefit; low-quality studies, on the other hand, showed improvements.
The authors' conclusion was clear and straightforward: "Currently, there is no reliable clinical evidence to support the use of collagen supplements to prevent or treat skin aging."
This pattern of funding bias is not unique to collagen. It recurs across various areas of the supplement industry and raises serious questions about how health decisions are being influenced by marketing rather than sound science.
Worse, many consumers believe that "natural" or "clean" products are automatically safe, ignoring potential side effects or the lack of regulation. There are documented cases of liver toxicity, adverse reactions, and even hospitalizations caused by widely promoted supplements.
Still, it's important to recognize that the direct risks of collagen supplements appear to be low, and for many, they are merely a superfluous expense, not a health risk. However, the financial cost and false sense of security can be significant.
People spend a lot of money expecting results that don't materialize. Furthermore, studies show that most collagen products are sold in forms and doses that don't promote absorption, such as gummies with low collagen content and added sugars.
Another little-discussed point is the animal origin of collagen: it is extracted from cows, pigs, chickens, and fish. There are even environmental and health concerns involved. "Vegan" versions of collagen don't actually contain collagen, only nutrients that would aid its natural production, such as vitamin C, zinc, and some amino acids.
At the same time, some emerging research is exploring collagen in contexts beyond aesthetics. Preliminary studies are investigating its role in athletic performance, tendon strengthening, and even in managing joint pain, such as osteoarthritis. In these cases, the results are varied and still inconclusive.
Some research suggests that taking collagen combined with vitamin C before exercise may stimulate natural collagen production in connective tissues. However, these studies are limited, conducted on small sample sizes, and often lack replication in more diverse populations.
Therefore, the central question is not whether collagen is useless, but whether there is sufficient scientific evidence to justify its use as a skin rejuvenation strategy. And, at this point, the answer appears to be: no.
Instead of betting on unproven promises, experts recommend investing in habits with proven effectiveness, such as a balanced diet rich in protein and antioxidants, daily sunscreen use, quality sleep, stress management, and, most importantly, physical exercise, especially resistance training, which stimulates natural collagen production and promotes overall skin and joint health.
Supplements should complement, not preempt, health and aging care. Questioning weak evidence, even when promising, is what drives science forward. After all, when it comes to our health, hope cannot replace rigor.
READ MORE:
Effects of Collagen Supplements on Skin Aging: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Seung-Kwon Myung, and Yunseo Park
The American Journal of Medicine. 3 May 2025
Abstract:
Collagen supplements are promoted to help aging skin. However, no meta-analysis of randomized controlled trials (RCTs) has examined their effects by funding source and study quality, which may influence outcomes. PubMed, Embase, and Cochrane Library were searched from inception to June 14, 2024. A total of 23 RCTs with 1474 participants were analyzed. In a meta-analysis of all 23 RCTs, collagen supplements significantly improved skin hydration, elasticity, and wrinkles. However, in the subgroup meta-analysis by funding source, studies not receiving funding from pharmaceutical companies revealed no effect of collagen supplements for improving skin hydration, elasticity, and wrinkles, while those receiving funding from pharmaceutical companies did show significant effects. Similarly, high-quality studies revealed no significant effect in all categories, while low-quality studies revealed a significant improvement in elasticity. There is currently no clinical evidence to support the use of collagen supplements to prevent or treat skin aging.
BBC
Collagen supplements: The secret to perfect skin, or marketing hype?
By Christine Ro
Comments