Do Fish Oil Supplements Improve Psoriasis?

The active ingredients in fish oils, known to contain anti-inflammatory activities, are omega-3 polyunsaturated fatty acids (ω-3 PUFAs). The use of fish oil supplements could therefore be effective in treating inflammatory diseases. Fish oil supplements have been suggested as a therapeutic option for psoriasis. In a new study, researchers evaluated what effects, if any, fish oil supplements have on psoriasis.

This was a meta-analysis of randomized, controlled trials (RCTs); the Central, Emabse, and Medline databases were searched on January 24, 2018, for relevant RCTs that explored the effects of fish oil supplement on psoriasis. RCTs were included if the participants had psoriasis, if the study intervention was fish oil/ω-3 PUFAs supplement compared with placebo or another active treatment, and if it was published in English. Researchers utilized the Cochrane Collaboration’s tool to determine risk of bias in selected studies. Primary outcomes included disease severity measured by the Psoriasis Area and Severity Index (PASI) score or involved body surface area, as well as adverse events. Other outcomes included the degree of psoriasis signs (erythema, scaling, and induration), as well as pruritus degree.

A total of 13 RCTs encompassing 625 patients were identified. In 11 RCTs, fish oil supplement was administered orally in either a capsule or oil, and in the remaining two RCTs, it was given intravenously as lipid emulsion. In three trials, capsules contained a combination of fish oil and evening primrose oil. Five RCTs found that fish oil supplement was beneficial for patients with psoriasis, but the other eight found no significant benefit compared with the control treatment.

Three RCTs encompassing 337 patients had suitable meta-analysis data. When using the PASI score, fish oil supplement was not associated with reduced disease severity (mean difference, –0.28; 95% confidence interval, –1.74 to 1.19).