It is intended to provide a composition such as a food or a drug which contains dihomo--linolenic acid (DGLA) and has a preventive or therapeutic effect on a skin disease a composition such as a food or a drug which contains dihomo--linolenic acid (DGLA) and has a preventive or therapeutic effect on a skin disease and a composition which contains dihomo--linolenic acid (DGLA) and is efficaciousin preventing or treating a disease relating to an increase in the mast cell count.
