While summer usually means trips to the beach and weekend BBQ’s in the sunshine, it is important to keep in mind how sun exposure and autoimmune disease relate.
Even modest amounts of ultraviolet (UV) exposure (i.e. sun exposure) and excessive heat can aggravate symptoms of autoimmune diseases and, in some cases, even trigger a full-blown flare.
Sun exposure and lupus
This is especially true in lupus patients. Studies have shown that when people with lupus are exposed to UV light, the production and release of a protein called type I interferon increases.
This protein is a potent driver of inflammation, activating immune cells called neutrophils. These activated neutrophils migrate not only to the skin, where UV light has done direct damage, but they also travel systemically and can cause widespread inflammation, particularly in the kidneys. These observations help to explain why sun exposure is such a dangerous trigger for lupus rashes, as well as kidney and other organ flares
Another study revealed that as temperatures and the humidity rise, there is an association with more severe lupus-specific organ activity. Skin rashes, kidney disease and inflammation of the lining around organs like the heart and lungs (called serositis) were all observed..
Sun exposure and autoimmune disease: Dermatomyositis
A study conducted by National Institute of Environmental Health Sciences (NIEHS) found unique links between women and UV exposure in a subset of autoimmune disease. "This study found that women who lived in areas with higher levels of UV exposure when they developed an autoimmune muscle disease called myositis were more likely to develop the form known as dermatomyositis, which weakens the muscles and causes distinctive rashes, instead of the form called polymyositis that does not have a rash," said Frederick W. Miller, M.D., Ph.D., chief of the Environmental Autoimmunity Group, Program of Clinical Research, at NIEHS.
5 Tips to protecting yourself from the sun
Regardless of your autoimmune disease diagnosis you don’t need to miss out on all of your favorite summertime activities, simply apply caution and protection. Below are some tips to protect yourself from the harmful effects of the summer sun and heat, while still enjoying the fresh air and sunny days of the season.
- Bring additional layers in cooling fabrics like linen and cotton to provide an extra barrier between your skin and the sun
- Whether you’re headed to the park or the beach, keep an umbrella with you to make sure that you have some shade.
- Hydrate! When the weather is warm we need even more water to replace what we lose through sweat. Make sure to aim for at least 70 ounces a day.
- Try to stay inside during the hottest part of the day, around 11am-2pm and if you are outside, consider bringing a handheld, portable fan or even some ice packs for the back of your neck so you can easily cool down.
- Apply (and reapply!) sunscreen. Using a clean, high-SPF sunscreen daily also helps to reduce the risk of a flare from UV rays and protects your skin. Since many sunscreen products contain chemicals that can also be triggering, make sure to read labels and go for a tested, safe brand. The Environmental Working Group’s website offers helpful information about the range of sunscreens with fewest chemicals. And remember to reapply every 60-80 minutes, especially if you are swimming or sweating.
Staying safe - all year round
It’s important to consider: people with autoimmune disease should take precautions to avoid excess UV light exposure all year round, even when the sky is overcast. A surprising amount of UV light is transmitted through cloudy skies. And the sun can be just as strong (if not stronger secondary to reflection off of snow) in winter months.
Keep these five tips in mind for all seasons to keep your autoimmune flares to a minimum.