How Can Weather Affect Psoriasis?

Psoriasis is a chronic autoimmune condition that causes symptoms to appear on the skin. People with psoriasis have an overactive immune response that maintains a level of inflammation that is not needed, which triggers the production of too many new skin cells more quickly than the old skin cells can be shed. The new skin cells push the old skin cells to the surface layer of the skin, where they build up and cause plaques to form.

Psoriasis is a chronic, lifelong condition, but most people cycle through periods of flare-ups when symptoms get much worse, and periods of remission when their symptoms are greatly improved or their skin is clear. Psoriasis triggers are things that can cause flare-ups, and each person psoriasis triggers are a little bit different. For many people, certain types of weather conditions can trigger psoriasis flare-ups. For other people, certain types of weather conditions may improve psoriasis symptoms.

A common psoriasis trigger is cold, dry, winter weather. During the winter, people also tend to get less exposure to sunlight1. Many people have psoriasis symptoms that are improved by regular periods of short-term exposure to sunlight, so they do not get this benefit during the winter. Another factor is that illnesses such as colds and flu are more common during the winter. Being sick can affect your immune system in ways that make psoriasis symptoms worse.

In the summer, there are more opportunities for exposure to natural sunlight and people tend to wear fewer layers of clothing that cover up smaller amounts of skin. People with psoriasis that responds well to sunlight may tend to have fewer flare-ups during the summer2. This may not be the case for people who have psoriasis that gets worse when affected skin is exposed to sunlight.

What does current research suggest about the link between weather and psoriasis?

A recent study examined the effect of weather conditions of people with psoriasis. It reported that most people with psoriasis who participated in the study had symptoms that improved in the summer and got worse during the winter, when humidity levels tend to be lower in the air is more dry3. The study did not find that muggy or rainy weather conditions had an effect on psoriasis symptoms, nor did it find any effect due to the indoor environment (for example, whether an air conditioner, radiator or fireplace was used). However, they did find that for some people with psoriasis, heat can worsen symptoms such as itching and redness.
The researchers conclude that some exposure tends to have a positive effect on symptoms for most patients. They also suggest that the reason dry winter air tends to make symptoms worse is that the low humidity causes the top layer of the skin to become thicker, which triggers the production of substances in the immune system that cause inflammation.

Tips for dealing with weather-related psoriasis symptoms

Try to identify your personal weather-related psoriasis triggers so that you can try to avoid them. During the winter, try to expose your affected skin to sunlight regularly for short periods of time (check with your healthcare provider about how long is safe for you)1. Take any steps you can to avoid getting sick, especially during the winter, by hand washing, getting enough sleep, and reducing stress.

During the cold, dry winter weather some people find it helpful to use a humidifier to hydrate the air in their homes. It may be helpful to avoid long, hot showers. Moisturizing your skin more often with emollients or oils during the winter can also help to control symptoms4.

Written by: Anna Nicholson | Last reviewed: July 2016.
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