A comprehensive new review synthesizing data from 113 clinical trials suggests that collagen might have positive effects on certain health outcomes. However, as is often the case in nutrition science, the realities are more intricate.
Collagen is a protein that our body naturally produces. It is essential for maintaining skin structure and elasticity, supporting bones and muscles, aiding wound healing, and protecting organs. Unfortunately, collagen production diminishes with age, prompting many individuals to seek supplements to replenish it.
However, not all forms of collagen are created equal. The collagen found in food may be less effectively absorbed than the smaller, more bioavailable peptides commonly found in supplements.
The hydrolyzed forms of collagen, which consist of shorter chains known as peptides, are believed to be more easily absorbed into the bloodstream, thereby facilitating their transport to tissues where they may exert biological effects, potentially benefiting skin, joint, and muscle health.
This recent review evaluated research published until March 2025, incorporating 16 systematic reviews that collectively included nearly 8,000 participants. The findings were generally cautiously optimistic.
Collagen supplementation was associated with moderate enhancements in muscle health and a decrease in pain for those with osteoarthritis. Improvements in skin elasticity and hydration were also observed; however, these benefits developed gradually, emphasizing the importance of consistent, long-term collagen intake rather than short-term use.
Some results were less definitive. Outcomes for skin elasticity and hydration varied based on the timing of the studies, with more recent findings revealing lesser improvements in elasticity but greater gains in hydration. This inconsistency indicates that the science surrounding collagen supplementation is still evolving.
About the author
Heba Ghazal is a Senior Lecturer in Pharmacy at Kingston University, London. This article is republished from The Conversation under a Creative Commons license. Read the original article.
The quality of the studies warrants careful examination. They employed a wide array of methodologies, dosages, and outcome measurements, making direct comparisons challenging.
Fifteen out of the 16 reviews were rated as low or critically low quality, not necessarily indicating that the supplements are ineffective, but pointing to methodological issues like failure to register studies beforehand and inadequate reporting of potential biases. Furthermore, many trials were short-lived and included limited participants, constraining our ability to draw reliable conclusions about long-term effects.
Not all collagen is equal
A significant challenge arises from the remarkable variability in collagen supplements. Some are sourced from animals such as cows, pigs, and chickens, while others derive from marine sources like fish, jellyfish, and shellfish. There are even vegan collagen alternatives. Some research involved oral supplements, whereas others focused on collagen dressings applied directly to the skin.
The processing method of collagen significantly influences the size and composition of the peptides in the final product, which affects their absorption and efficacy within the body. Grouping these diverse products in a single analysis can obscure as much as it reveals.
Individual variances play a crucial role as well. Factors like sun exposure, smoking habits, sleep quality, environmental conditions, and hormonal levels all influence how skin ages and how it may respond to supplements. If studies do not account for these variables, it becomes challenging to ascertain whether any observed changes are genuinely attributable to collagen or merely reflect differences in participants’ lifestyles.
This review contributes to a growing body of evidence indicating that collagen supplements are not merely expensive placebos. There appear to be tangible, albeit modest, benefits—particularly regarding skin hydration, joint pain relief, and muscle health.
Nevertheless, significant gaps remain in the research base. Without more rigorous and standardized studies, it is difficult to discern what specifically drives these benefits and which individuals are most likely to experience them. Future studies should clearly define the type of collagen used, the dosage, the method of consumption, and the characteristics of the participants involved.
In conclusion, while there is promising evidence supporting the potential benefits of collagen supplements, the intricacies of individual responses and the varying qualities of the supplements warrant further investigation. Only with more comprehensive research can we fully understand the best uses and possible limitations of these products.
