The lazy, hazy days of June, July and August torture people with summer seasonal affective disorder (SAD), a condition leaving them depressed and lethargic while others frolic at the beaches and celebrate with picnics.

About 5 percent of American adults experience extreme versions of SAD, which is typically associated with the dark, cold winter months but also strikes in the heat of the summer. After coining the term SAD in 1984 to describe people struggling in the winter, psychiatrist Dr. Norman Rosenthal was approached by people having the same reaction each summer. He pursued the concept and found that while causes and reactions differed slightly, the result was a similar emotional state.

“The differences are in how people experience their symptoms,” said Dr. Valeria Martinez-Kaigi, a health psychologist at Hartford HealthCare. “With a summer seasonal pattern, people report their mood as more agitated vs. sad. They also report more insomnia and decreased appetite as opposed to winter when people report more hypersomnia, or sleeping too much, and increased appetite.”

Though less common in the summer, SAD can be debilitating and even confusing for people who feel depressed, she said, while others are thrilled to enjoy warmer weather and its associated outdoor activities.

Commonly reported triggers for summer SAD are heat and humidity. That, research revealed, might be because the same body chemicals regulating mood are linked to body temperature as well. Inhalation of pollen in the summer can also trigger a release of biological compounds connected with depression.

There is also more peer pressure to be happy and outdoors in the summer. And people seem more accommodating and accepting of people who feel depressed in the winter.

To be properly diagnosed, you must experience either version of SAD for two or more consecutive years, with no symptoms outside of the season, Dr. Martinez-Kaigi said.

“It is clinically significant depression with a seasonal pattern,” she said.

Anyone feeling summer SAD can turn to any evidence-based treatments recommended for major depressive disorder, she continued. The first step is to reach out to a mental health provider to explore some of these treatments, such as cognitive behavioral therapy, or medication.

These simple tips can combat the impact of the heat on your mood:

  • Escaping the heat in air conditioned spaces.
  • Taking cool showers or baths.
  • Decreasing exposure to the summer’s intense sunlight with dark sunglasses or room-darkening curtains.

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