For people with eczema, summer isn’t always so sweet. The soaring temps and warm-weather activities, like swimming and spending hours in the sun, can be eczema triggers.
You may find that surprising, since eczema commonly worsens in the winter months, when the air is cold and dry, according to Johns Hopkins Medicine. “Although wintertime is actually the most common time for flares to occur, eczema can flare year-round,” says Shari Marchbein, MD, a board-certified dermatologist with Downtown Dermatology in New York City. In fact, a study published in January 2021 in The Journal of Dermatology found that one‐third of children with difficult‐to‐treat atopic eczema reported flares in spring and summer.
So why is summer such a tricky time for eczema? For one, increased heat and humidity can lead to more sweating, says Susan Bard, MD, a board-certified dermatologist with Vive Dermatology Surgery and Aesthetics in Brooklyn, New York. Sweating is enemy No. 1 for eczema-prone skin in the summer, because it can lead to increased aggravation, according to a study published online in January 2017 in BioMed Research International.
“Sweat contains various salts that can be irritating to broken skin, such as eczema skin,” Dr. Bard says. More specifically, sweat can contain zinc, copper, iron, nickel, cadmium, lead, manganese, sodium, and chloride, and when these build up, irritation could result, according to the National Eczema Association. You may notice eczema worsens mainly in areas where moisture gets trapped, such as the elbows, the back of the neck, or the backs of the knees.
Daniel P. Friedmann, MD, a board-certified dermatologist with Westlake Dermatology in Austin, Texas, adds that other seasonal environmental factors could also be to blame. “An increase in allergens in the environment — pollen, for example — can incite histamine release, which causes itching,” he says.
Jumping into the water and slathering on sunscreen — two common summertime habits — can also cause the eczema you thought you had under control to go into turmoil.