The exact cause is unknown. Current information suggests that psoriasis is related to the result of two main factors:
In individuals with certain genetic predisposition faulty signals sent by the body's immune system accelerate the growth cycle in skin cells, which pile up on the surface and the body cannot shed them fast enough. However, many people with psoriasis have no family history of the disease.
Red scaling patches are caused by an increase in the number of skin cells on the most superficial layer of the skin. Normally, skin cells mature and shed from the surface of the body. This process takes approximately 4 weeks. People with psoriasis shed skin cells as fast as every 3 to 4 days. This excessive amount of skin cells form the skin lesions of psoriasis.
Symptoms of psoriasis include red, scaling patches on the skin, itching, and thickening, cracking, and blistering of the palms or soles of the feet. Symptoms may vary from mild to a severe, disfiguring, disabling condition.
According to the type of skin lesions and the location of the skin patches psoriasis is classified according to several types:
Erythrodermic - psoriasis causes extensive reddening and swelling of skin.
Plaque psoriasis - This is the most common form of psoriasis (about 80 percent of people with psoriasis have this type). It causes raised red skin lesions. These skin red patches develop white scales. The knees, elbows, scalp, trunk and nails are the most common locations, although it can appear on any skin surface.
Inverse psoriasis - causes smooth red lesions in the folds of the skin.
Guttate psoriasis - causes small skin lesions that look like drops of fluid.
Pustular psoriasis - forms blisters filled with thick white material.
Psoriatic arthritis - is a form of joint disease that is similar to rheumatoid arthritis plus psoriasis.
Certain factors may trigger plaque development in people with psoriasis. Among these factors are: skin damage (chemicals, infections, scratching, sunburn), alcohol, hormonal changes, smoking, certain medication including beta-blockers, non-steroid anti-inflammatory drugs, and stress.
Psoriasis can have an emotional, as well as a physical, impact on people. Psoriatic arthritis, a form of joint inflammation that occurs in some people who have arthritis, can be painful and disabling.
No, psoriasis is not contagious. No one can "catch" it from another person.
The best diet is the one that makes the individual feel the best, because people with psoriasis benefit from a healthy lifestyle and eating habits, just like everybody else. Many people report that certain foods either aggravate or improve their skin condition. There is no specific diet that people with psoriasis should follow. However, several dietary regimens have been suggested under naturopathy.