Our skin can behave differently with each season, but if you have psoriasis the weather may REALLY affect your itching and redness. Psoriasis is a skin condition that affects the body's natural process of shedding dead skin cells, causing patches of rough, red, itchy skin. Winter flare-ups are common with psoriasis. The cold, dry air and decreased sun exposure of winter can worsen psoriasis symptoms, leaving you with itchier, redder skin. Also, anything that affects your immune system can in turn, affect your psoriasis. Which means a winter cold or flu can trigger a psoriasis flare. On the other hand, the hotter, more humid air of summer can mean psoriasis relief. A certain amount of ultraviolet light from the sun can reduce the itching and inflammation of psoriasis, and increase your body's production of vitamin D, which is known to improve psoriasis symptoms. In the winter, try to avoid getting sick by washing your hands and staying rested. Keeping a humidifier on in your home can reduce dry skin and ease psoriasis symptoms. And a topical vitamin D ointment from your doctor can replace winter's lacking UV rays and also improve irritated skin. In the summer, remember that even though SOME sun can improve your psoriasis, too MUCH can worsen symptoms and damage skin, so it's important to keep sun exposure to a minimum - meaning don't get burned! -- and wear sunscreen. For more information on psoriasis, watch other videos in this series.