Salmon oil is a rich source of omega-3 polyunsaturated fatty acids (PUFAs), primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These compounds have anti-inflammatory properties, which are of interest in the management of psoriasis, a chronic inflammatory skin disorder. Several small clinical trials and observational studies have explored the effects of oral fish oil supplementation in people with psoriasis, with mixed results. Some studies report modest improvement in psoriasis severity scores and lesion scaling, while others find little to no benefit. Meta-analyses and systematic reviews generally conclude that while there may be a mild positive effect, the evidence is limited by small sample sizes, short study durations, and variability in dosing and formulations.

Mechanistically, omega-3 fatty acids are thought to modulate inflammatory pathways by decreasing the production of pro-inflammatory cytokines and eicosanoids involved in psoriatic skin lesions. The American Academy of Dermatology acknowledges that fish oil may be considered as an adjunct in some cases, but it is not a primary or highly effective treatment. Overall, while there is some scientific rationale and preliminary clinical evidence for the use of salmon oil in psoriasis, it is not robustly validated, and more well-designed, large-scale studies are needed to clarify its role.