Nutrition and psoriasis.

Nutritional supplementation may provide a viable treatment alternative in patients with psoriasis. Randomized, controlled trials have shown the effectiveness of topical vitamin A and D derivatives, intravenous ω-3 fatty acids, oral inositol, and various combined therapies. Dual therapies of ultraviolet B phototherapy and fish oil, retinoids and thiazolidinediones, and cyclosporine and a low-calorie diet were effective in the treatment of psoriasis in randomized, controlled trials. This contribution also reviews the potential negative effect of alcohol and the potential positive effects of vitamin B(12), selenium, retinoic acid metabolism-blocking agents, and a gluten-free diet in the treatment of psoriasis.