Effects of fish collagen peptides and probiotics on skin health and their potential synergistic interactions: A comprehensive review

The skin is the body's main barrier against the external environment. Exposure to ultraviolet (UV) radiation can cause DNA damage, collagen breakdown, and excess reactive oxygen species (ROS). Over time, these changes may lead to skin aging, wrinkles, and a higher risk of skin cancer. Fish collagen peptides (CPs) and probiotics show promise as functional supplements for skin health. Absorbed CPs boost endogenous collagen and hyaluronic acid (HA) synthesis, while probiotics strengthen the skin barrier by reducing inflammation/oxidative stress and regulating short-chain fatty acid (SCFAs) metabolism. Crucially, they exhibit synergistic effects through the gut-skin axis. However, current research focuses primarily on their individual actions, leaving their combined mechanisms unexplored. This review comprehensively examines CPs sources and bioactivities, probiotic benefits for skin, and their gut-skin axis synergy potential. It aims to provide a theoretical foundation for developing combined intestinal-skin interventions and novel skin health strategies. • Collagen peptides extraction methods from fish and their effects on skin health. • Fish-derived collagen peptides regulate gut microbiota by promoting probiotic growth and metabolic function. • Fish-derived collagen peptides and probiotics synergize through the gut-skin axis to improve skin health.