In most cases, your primary care doctor or dermatologist will be able to diagnose psoriasis by examining your skin. However, since psoriasis can look like eczema and other skin diseases, diagnosing it can sometimes be difficult.
If your doctor isn't sure whether you have psoriasis, he or she may order a biopsy. Your doctor will remove a small sample of your skin and have it looked at under a microscope.
Many people think that what they eat affects their psoriasis, but no studies have shown a connection. Doctors can’t be sure there's no link between some foods and psoriasis. It's just that so far, there's no proof.
According to most experts, the best dietary advice for people with psoriasis is the same as for anyone else: Eat a diet low in fats and sweets and high in fruits and vegetables. While you're at it, get regular exercise -- being overweight can make psoriasis worse and keep your medication...
Bruce E. Strober, MD, PhD. associate director of Dermatopharmacology, Department of Dermatology, New York University School of Medicine; co-director of the Psoriasis and Psoriatic Arthritis Center; consultant for Amgen, Biogen, Genentech, Fujisawa, and 3-M. Jeffrey M. Weinberg, MD, director of the Clinical Research Center, St. Luke's-Roosevelt Hospital Center, New York City; assistant clinical professor of dermatology, Columbia University College of Physicians and Surgeons; consultant for Amgen and Genentech. National Institute of Arthritis and Musculoskeletal and Skin Diseases web site. American Academy of Dermatology web site. WebMD Medical Reference with Healthwise: "Psoriasis." American Academy of Dermatology, PsoriasisNet web site. National Psoriasis Foundation web site. Abel, E. "Dermatology III: Psoriaisis," ACP Medicine, April, 2005.