Seasonal Affective Disorder (SAD) impacts an estimated 5 percent of individuals in the U.S. population. Most people associate SAD with wintertime, when short, dark days and frigid temperatures take their toll on mood and mental health. Outside of a clinical diagnosis, it’s common or even culturally expected to experience at least some degree of mood or energy shift in the winter months.
However, an estimated 10 percent of individuals with SAD experience their symptoms only during the spring and summer months. Summer SAD is unique in that it runs counter to the cultural expectation of increased happiness, energy, and social activity during the warmer, brighter months.
It can be disorienting and isolating to experience symptoms of depression during a time when you anticipate feeling lighter and more joyful. Individuals with summer SAD are often left questioning what’s wrong with them for struggling so much during a time when everyone else seems to be thriving.
What Is Summer SAD?
Despite its prevalence, summer SAD is understudied. Some people who experience summer SAD may go undiagnosed for many years.
SAD is not a standalone diagnosis. Rather, it is recognized as a subtype of major depressive disorder, characterized by changes in mood, sleep, appetite, energy, concentration, and outlook that significantly get in the way of everyday life.
What distinguishes all types of SAD is the seasonal pattern, when symptoms emerge predictably at the same time each year and resolve fully as the season changes. In summer SAD, symptoms arise during the spring or summer and remit in the fall or winter.
Some research indicates that some symptoms of summer SAD look uniquely distinct compared to winter SAD (Wehr et al., 1991). Whereas winter SAD involves excessive fatigue, sleeping too much, and overeating, summer SAD is the inverse: restlessness, general feelings of agitation, trouble sleeping, and poor appetite.
Why Do People Experience Summer SAD?
There is no exact cause of summer SAD, but instead a mix of biological, environmental, psychological, and social factors.
As in winter SAD, summer SAD appears to involve disruptions to the body’s natural circadian rhythm alongside significant changes in daylight hours. In those with summer SAD, the longer, warmer days and increased sun exposure make it difficult to fall and stay asleep. This can be thought of as a mirror image of winter SAD, when the short, dark days can lead to low energy and sleeping too much.
High temperatures can also play a role. Heat exposure can lead to symptoms that mimic depression, including fatigue, irritability, and loss of appetite. For those who are heat-sensitive or typically enjoy outdoor activities, the summer months can mean long stretches of feeling cooped up indoors.
There are also psychological and social aspects that contribute to summer SAD. Mainstream culture tells you that summer is supposed to be the most enjoyable time of the year: vacations, beach days, outdoor concerts, and barbecues. For those struggling with summer SAD, the stark contrast between expectations and reality can lead to guilt, self-criticism, avoiding hobbies, and isolation. This vicious cycle of feeling worse and doing less can perpetuate depression.
What Helps Alleviate Summer SAD?
Fortunately, there are many approaches that can help reduce summer depression.
Maintain consistent routines. Routines can easily be thrown off alongside significant changes in daylight hours and busy schedules, but the mind and body thrive on consistency. Anchor your day by maintaining consistent bed and wake-up times, having meals at predictable hours, and scheduling regular exercise.
Seek out cool, dark environments. Whereas the treatment for winter SAD involves intentionally increasing access to light exposure, the intervention for summer SAD is the opposite: regular exposure to dark, cool environments can help reduce symptoms. If this is not possible at home, seek out exposure in movie theaters, air-conditioned public spaces, or shady waterfront areas.
Optimize your bedroom environment. Because sleep disturbance is a hallmark feature of summer SAD, making efforts to improve sleep hygiene can help. The bedroom should be dark, quiet, and cool. Tools such as blackout curtains, an eye mask, or a box fan can create a space more conducive to restful sleep.
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Switch up hobbies. If you tend to enjoy outdoor hobbies during cooler times of year, consider alternative or modified activities during the hotter months. We tend to feel better when we have things on the calendar to which we look forward, and regular engagement in hobbies can boost mood. Plan at least two or three activities for yourself each week—they do not need to be anything time-consuming, expensive, or complicated. For example, try a new coffee shop, start a puzzle, or go for a walk first thing in the morning.
Consider therapy and/or medication. If your symptoms continue to interfere with work, relationships, or daily life or cause significant distress, consider seeking out support from a mental health professional. Treatments such as cognitive behavioral therapy (CBT) and acceptance and commitment therapy (ACT) can help you deepen your understanding of your thoughts, emotions, and behaviors, and give you tools for coping with stress. Antidepressant medication can also be helpful, especially when symptoms are severe.
Moving Forward
Summer SAD can be a disabling and isolating experience, made more difficult by the fact that it arrives at a time when the world around you seems to be thriving. For some, simply giving the struggle a name feels like a relief in itself.
If you felt seen in this article, consider reaching out to a mental health professional who can help you understand your seasonal patterns and build a plan for the months ahead.
To find a therapist near you, visit the Psychology Today Therapy Directory.