There is scientific evidence supporting the use of certain fatty acids, particularly omega-3 and omega-6 fatty acids (often found in fish oil, borage oil, evening primrose oil, and flaxseed oil), as adjunctive therapy for eczema (atopic dermatitis). Eczema is associated with skin barrier dysfunction and inflammation, and fatty acids are believed to modulate inflammatory processes and improve skin barrier function.

Several randomized controlled trials and meta-analyses have evaluated the effects of fatty acid supplementation, especially gamma-linolenic acid (GLA) from evening primrose oil and borage oil, as well as EPA and DHA from fish oil. Some studies report modest improvements in symptoms such as itching, scaling, and overall disease severity, while others find minimal or no benefit. The European Academy of Dermatology and Venereology and other guidelines note that evidence is mixed but suggest that supplementation may help in some cases, particularly in individuals with confirmed fatty acid metabolism deficiencies.

Overall, while fatty acid supplementation is not considered first-line therapy, there is moderate scientific support for its adjunctive use in eczema, especially in certain subgroups. The evidence does not universally support the efficacy of all proprietary blends, as formulations and doses vary, but the rationale is based on the anti-inflammatory and skin barrier-supporting properties of specific fatty acids.