Melatonin

Melatonin is a hormone naturally produced by the body to regulate sleep-wake cycles, and it is also synthesised and present within skin tissue itself. In skincare formulations, melatonin functions as a topical antioxidant, working to neutralise free radicals and support the skin's natural defence systems.Beyond simple antioxidant activity, melatonin operates through multiple biological pathways in the skin, including receptor-mediated mechanisms and direct interactions with cellular structures. This multifaceted action distinguishes it from single-function antioxidants.

Melatonin operates through a layered system of actions. It directly scavenges free radicals without requiring enzymatic conversion, offering immediate antioxidant protection. It also binds to specific receptors on skin cells (MT1 and MT2 receptors) and interacts with nuclear receptors that regulate cellular health and inflammation responses.Research indicates that topical melatonin may influence the skin microbiota—the community of bacteria living on the skin surface. By promoting beneficial bacterial populations and their metabolites, melatonin may indirectly support skin barrier function …

Melatonin is typically found in serums, moisturisers, and targeted treatments at low concentrations. Apply to clean skin once or twice daily, depending on formulation instructions. It pairs well with other antioxidants and can be used alongside retinoids or other active ingredients, though patch testing is advisable if you have sensitive skin. Melatonin does not require special storage conditions beyond standard cool, dark storage for most skincare products.

Melatonin is generally well-tolerated in topical skincare formulations. No significant toxicity concerns have been identified at cosmetic concentrations. Those with known melatonin sensitivity or taking oral melatonin supplements may wish to patch test first, though topical application carries minimal systemic absorption.