Cod liver oil (CLO) is a nutritional supplement derived from the livers of Atlantic cod. Historically, it was used to treat conditions like rheumatism and prevent rickets, a disease caused by vitamin D deficiency. Today, CLO is recognized as a potent source of specific nutrients that offer benefits beyond bone health. This article explores the scientific basis for using cod liver oil to promote skin health through its unique nutritional profile and systemic effects.
Essential Components for Skin Wellness
Cod liver oil is a concentrated source of three primary components that contribute to overall skin function: Omega-3 fatty acids, Vitamin A, and Vitamin D. The Omega-3 fatty acids are primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These polyunsaturated fats are integral to cellular structure and communication throughout the body, including the skin.
The oil also naturally contains high levels of the fat-soluble vitamins A and D. Vitamin A is present as retinol, which is well-known for its role in cell differentiation. Vitamin D helps regulate calcium and phosphorus levels, but also influences various other biological processes. This combination of fats and vitamins forms the foundation for CLO’s dermatological benefits.
Therapeutic Effects on Skin Barrier and Inflammation
The components of cod liver oil work synergistically to address skin concerns rooted in inflammation. The Omega-3 fatty acids, EPA and DHA, exert powerful anti-inflammatory effects by altering the production of inflammatory signaling molecules. This systemic reduction in inflammation can help soothe inflammatory skin conditions like acne, eczema, and psoriasis, which manifest as redness and irritation.
EPA and DHA also help reinforce the skin barrier function, the outermost layer responsible for retaining moisture and protecting against environmental aggressors. A stronger barrier improves skin hydration and prevents transepidermal water loss. The Vitamin A content supports the normal production and repair of skin cells, regulating cell turnover and maintaining the integrity of this protective barrier. Vitamin D further contributes by supporting skin cell growth and modulating immune responses.
Dosage and Method of Application
Cod liver oil is typically consumed orally, either as a liquid or in capsule form, to provide systemic benefits to the skin. Oral consumption allows the Omega-3s and vitamins to be absorbed into the bloodstream, influencing inflammation and cell function throughout the body.
For adults, a common daily dosage is often between one and two teaspoons of the liquid oil. Capsules are also widely available, with recommended doses generally ranging from one to three capsules daily, depending on nutrient concentration. While CLO can be applied topically, this method is less common for achieving the broad, systemic skin health benefits linked to its anti-inflammatory properties.
Considerations for Safe Consumption
A primary concern with cod liver oil supplementation is the risk of excessive Vitamin A intake, known as hypervitaminosis A. Because CLO is derived from the liver, it contains high concentrations of preformed Vitamin A. Consuming just one tablespoon of CLO can potentially exceed the adult tolerable upper intake level (UL) of 3,000 micrograms (µg) per day.
Chronic overconsumption can lead to adverse effects, including dry or peeling skin, hair loss, headaches, and liver problems. Individuals taking CLO should be mindful of other Vitamin A sources in their diet or supplements to avoid toxicity. Furthermore, the high Omega-3 content may interact with blood-thinning medications, and some individuals may experience mild digestive upset, such as heartburn or loose stool.