Seasonal affective disorder (SAD), more recently known as major depressive disorder with a seasonal pattern, mostly affects people in the winter months. However, some people can experience it in the summer.

As days grow shorter and the weather turns colder in winter, many people find themselves feeling a little down. But for some people, this sadness is more than just a passing feeling and is actually a symptom of SAD.

SAD is a type of depression that usually occurs during the winter months when there is less daylight. It affects around 5% of people in the United States annually.

In rare instances, some individuals experience SAD in the summer. If individuals feel unusually down, tired, or anxious during the summer, they should check with their doctor to see if they have summer SAD. Medical treatment, counseling, and lifestyle changes can make living with summer SAD easier.

This article looks at summer SAD, its differences from winter SAD, causes, and treatment.

Sandals and an ice cream on the floor, summer SADShare on Pinterest
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SAD is a recurrent major depressive disorder with a seasonal pattern. It usually begins in the fall and continues into the winter months. Individuals tend to then experience a stable mood during spring and summer. However, SAD can sometimes involve depression in the spring or early summer instead.

SAD typically affects people living in higher, more northern latitudes, with younger people and females more at risk. Although there has been far less research on summer SAD, according to one early study from 1984, living close to the equator in hotter areas may increase the risk of developing the condition in summer.

Learn more about SAD here.

Experts remain unsure why some individuals experience SAD. However, theories propose that in winter SAD, the decreased hours of sunlight affect a person’s circadian rhythm. This cycle is the natural 24-hour body clock that controls physical, mental, and behavioral patterns in response to light and dark.

In winter, shorter days and longer hours spent inside reduce a person’s exposure to sunlight. Therefore, people with winter SAD may feel lethargic, gloomy, and listless. They may experience symptoms such as oversleeping, overeating, and weight gain.

In summer onset SAD, the opposite is true. It is the long hours of sunlight that can trigger problems.

The reasons behind summer SAD remain a puzzle, but theories include biological explanations. For example, people with SAD may overproduce melatonin, a hormone that responds to darkness and controls the sleep-wake cycle. Sunlight turns off melatonin production. This means that long summer days result in lower levels of melatonin. People with summer SAD may experience insomnia or sleep problems because they do not have enough melatonin.

The causes of summer SAD are not always clear, and evidence is scarce, although it seems logical that melatonin levels play a role. People with SAD may also have reduced levels of serotonin, a chemical that helps regulate mood. The changes in melatonin and serotonin could affect a person’s daily circadian rhythms, and they may have trouble adjusting to seasonal changes.

Other potential causes include allergies, as some research indicates that airborne pollen levels can affect mood.

Additionally, summer can bring challenges that could affect an individual’s mood and mental health. For example, individuals with body image concerns may find that summer’s hotter months and lighter clothing trigger anxiety and worry.

The longer daylight hours, shorter nights, and increased temperatures can also cause sleep disruptions. As a result, people may not sleep as well as they need to for optimal mood and health.

Together, these factors could contribute to summer SAD.

In contrast to winter SAD, the symptoms of summer SAD include:

Treatment for winter SAD typically includes a combination of antidepressant medication, light therapy, Vitamin D supplements, and counseling such as cognitive behavioral therapy.

Doctors have not yet established optimal treatment for summer SAD, but several things may help, including:

  • Improving sleep quality: As summer SAD connects to sunlight, people may find that spending time in darkened rooms before bedtime helps them sleep better. Trying other techniques that help them relax, such as yoga or meditation, may also improve sleep. People should also avoid caffeinated products and alcohol, which can affect sleep.
  • Using air-conditioning: If people find the heat and humidity of summer stressful, using air-conditioning may improve their mood and sleep quality.
  • Reducing stress: Chronic stress increases an individual’s risk of experiencing depression. Therefore, finding ways to lower stress can positively impact an individual’s mood.
  • Eating a healthy diet: If an individual experiences a loss of appetite, they may not eat enough essential nutrients to keep them well. Therefore, individuals should try to eat small, manageable, but nutrient-dense meals.

If a person has not felt like their usual self and feels low and anxious, they should speak with their doctor.

A doctor can rule out other medical conditions that can cause symptoms similar to summer SAD. Additionally, they can refer the individual to a mental health professional or recommend medications to lift their mood.

People should seek help to prevent the symptoms of summer SAD from impacting their lives. A doctor can help individuals find ways to manage stress and identify healthy coping strategies.

Seasonal affective disorder (SAD) is a type of depression that typically affects people during the winter months when there is less daylight. However, some individuals experience SAD in the summer.

The two types of SAD vary by symptoms. For example, winter SAD involves oversleeping, overeating, and a low mood. Conversely, individuals with summer SAD may experience insomnia, lack of appetite, irritability, and anxiety.

Experts remain unsure as to the causes of both winter and summer SAD. Still, it appears that upsets to the circadian rhythm and changes to the hormone melatonin and neurotransmitter serotonin may play a role.

Additionally, the increased heat, humidity, and daylight hours of summer can cause disruptions to sleep that affect a person’s mood.

If a person feels that their mood is low and they may have symptoms of depression, they should seek their doctor’s advice. A doctor may recommend antidepressants, therapy, and a range of lifestyle changes that can help reduce stress and improve sleep quality.