Skin Aging and Type I Collagen: A Systematic Review of Interventions with Potential Collagen-Related Effects

Aging leads to a decline in skin function due to intrinsic factors (genetics, hormones) and extrinsic factors (sun exposure, pollutants). Type I collagen plays a vital role in maintaining skin integrity and elasticity. As aging progresses, collagen synthesis diminishes, resulting in weakened skin structure and wrinkle formation. This systematic review explores the role of type I collagen in skin aging by summarizing key clinical findings. A systematic search was conducted using PubMed and ScienceDirect as the primary databases, including studies published between 2014 and 2025 that addressed type I collagen and skin aging. Eleven clinical studies were selected following PRISMA guidelines. The results consistently show the decline of type I collagen as a central contributor to dermal thinning, loss of elasticity, and the appearance of wrinkles and sagging. Clinical trials demonstrate that collagen supplementation, particularly from hydrolyzed fish cartilage and low-molecular-weight peptides, enhances collagen production, improves skin hydration and texture, and reduces signs of photoaging. Overall, the evidence emphasizes the critical role of type I collagen in skin aging and suggests that targeted collagen supplementation may serve as an effective strategy to maintain skin structure and combat visible signs of aging.