Psoriasis is one of the most common chronic inflammatory skin disorders, affecting about 2% of the general population. It is considered to be a T-cell-mediated inflammatory skin disease which is characterized by hyper-proliferation and poor differentiation of epidermal keratinocytes. Even if the susceptibility to psoriasis is inherited, the inflammatory reaction is modulated by diet, lifestyle and environmental factors such as infections and stress. Polyunsaturated fatty acids (PUFAs) are showing promise as safe adjunctive treatments for many skin disorders, including psoriasis.