Causes of PsoriasisNo one knows exactly what causes psoriasis, but doctors and researchers believe genetics play a role. Most researchers agree that the immune system is somehow triggered by mistake, and as a result, the growth cycle of skin cells increases. Normally, the skin cell cycle lasts 28 to 30 days. But a psoriatic skin cell takes only three to four days to mature and move to the surface. Instead of falling off, the cells collect and form lesions. Certain factors appear to "trigger" or cause psoriasis. These triggers can include emotional stress, injury to the skin, certain types of infection and reactions to some drugs. Other triggers may include weather, diet and allergies. Triggers will vary from person to person and what may cause one person's psoriasis to flare may produce no reaction in another individual. | 
