Can collagen help reduce scars?

Due to its biocompatibility and biodegradability, collagen has numerous biomedical applications. Researchers have highlighted that collagen hydrogels are the best candidate materials for making dressings. This is due to their three-dimensional structure, similar to that of the skin's extracellular matrix, and their hydrating properties, ensuring that wounds benefit from a moist environment conducive to healing.

Moreover, when applied as a dressing, collagen acts as a natural scaffold and a substrate for the growth of new tissues. It provides the wound with an alternative source of collagen that can be degraded by matrix metalloproteinases (MMPs) as a sacrificial substrate, allowing the native endogenous collagen to continue the normal wound healing process. Indeed, the inflammatory phase of healing is associated with high levels of MMPs, which are normally regulated by certain physiological processes. However, sometimes healing is stalled, leading to the formation of a scar. Collagen can help to restore this process. Additionally, it has been shown that this active ingredient possesses anti-inflammatory and immunomodulatory properties, as well as antimicrobial activity, which are useful for supporting healing.

A recent study conducted by ASSAR and his team on rats with dorsal wounds has demonstrated that collagen extracted from Nile Tilapia, a fish, can accelerate wound healing by stimulating the expression of growth factors TGF-β1 and b-FGF, as well as the proliferation of fibroblasts and myofibroblasts. During the study, the rats were divided into two groups: a control group and a collagen-treated group. The wound surfaces were measured over 15 days and histopathological examinations were performed. Differences were observed from the first week, showing that collagen allows for a faster reduction in wound surface area. The graph below, extracted from the article, indicates a significantly greater improvement from day 9 onwards.

Collagen appears to have healing effects. However, no study has yet shown that it can reduce already formed human scars.

Somewhat less studied, collagen supplementation could also positively impact wound healing. Recent research was conducted with 31 individuals suffering from burns who were admitted to the hospital. In addition to clinical treatment, patients were randomly assigned to receive either a collagen-based supplement or an isocaloric placebo for 4 weeks. By week 2, wounds were completely healed in 50% of the patients in the collagen group and in 6.7% of the patients in the control group. By the end of the study, the wounds of all patients in the collagen group and 40% of the patients in the control group were fully healed. Oral collagen intake could thus have a favourable effect on wound healing, which would be interesting to confirm through further studies. However, no data currently supports the claim that it can reduce existing scars.