Fish Oil

Fish oil is derived from fatty fish and contains high levels of omega-3 polyunsaturated fatty acids (PUFAs), primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These molecules are also found naturally in human sebum, making fish oil a recognisable ingredient to the skin.In skincare formulations, fish oil functions as a skin conditioner and emollient. It works by delivering these beneficial fatty acids topically, which may help maintain skin hydration and support the skin barrier.

Fish oil's primary mechanism involves its omega-3 fatty acids competing with inflammatory compounds (particularly arachidonic acid) in the skin, thereby reducing the production of pro-inflammatory molecules called eicosanoids. This may help calm inflammatory skin conditions.Additionally, the PUFAs in fish oil have antioxidant properties that may counteract reactive oxygen species (ROS) — unstable molecules generated by environmental stressors like air pollution and UV exposure. By reducing ROS, fish oil may help protect collagen and prevent premature skin degradation.

Fish oil is typically found at very low concentrations in skincare formulations (around 0.1% of products). It works best as part of a layered routine — apply it to clean, slightly damp skin to help lock in hydration, or mix it with other moisturisers. If using a pure fish oil, a small amount goes a long way; start with a drop or two and build tolerance gradually.

Fish oil is generally well-tolerated topically. Those with fish allergies should check product labelling. Store away from direct sunlight and heat, as the oil can oxidise and become rancid, reducing efficacy.