Seasonal Affective Disorder/Seasonal-Pattern Depression

During winter, many people notice the days getting shorter and decreased exposure to sunlight. Some may feel more withdrawn and experience seasonal-pattern changes to their sleep, energy, and mood. Winter seasonal depression (sometimes referred to as seasonal affective disorder or SAD) consists of symptoms which recur during the winter and get better with the approach of spring and summer.

In order to be diagnosed as winter seasonal-pattern depression, symptoms must recur for at least two consecutive winters. In the US, reported rates of winter SAD are higher in northern states, although it can occur in sunnier, southern locations as well.

Many people who experience winter SAD have "atypical" symptoms of depression such as increased sleep duration, increased appetite, and carbohydrate craving, according to the American Psychiatric Association. Symptoms of SAD are also reviewed by the Mayo Clinic.

Decreased daylight in winter can affect your biological clock (circadian rhythm). With shorter winter days and longer periods of darkness, the body produces the “darkness hormone” melatonin in a different pattern, which can affect sleep and mood. This may in part contribute to SAD.

During the Covid-19 pandemic, SAD symptoms may interact with Covid-19 stresses and isolation. The combination can make the winter months doubly difficult. The Cleveland Clinic offers tips for coping with Covid pandemic stress and seasonal mood symptoms.

People can plan ahead to cope with SAD symptoms. For sighted people, natural sunlight or bright light from light therapy boxes, typically during the morning or at midday, can help suppress the production of melatonin. Getting increased (safe) amounts of light can help with SAD, and the medical reference Up to Date summarizes several research studies on light therapy. Talk to a medical or mental health clinician about optimal, safe ways to increase light exposure based on your health conditions and symptoms. There is information on seasonal changes in mood and the use of light therapy boxes from Johns Hopkins University and the Mayo Clinic. Some may be able to get extra sunlight by taking a mid-winter vacation.

Since SAD symptoms include daytime fatigue, it can be tempting to increase caffeine. However, taking more caffeine to try to combat feelings of low energy during the day can increase feelings of anxiety or disrupt sleep at night. Alcohol can also have a negative impact on sleep quality. Instead, talk with a medical or mental health provider about strategies such as morning or midday light and physical activity to help boost energy.

Cognitive behavioral therapy (CBT) can help seasonal-pattern depression SAD. Behavioral sleep medicine providers can help you develop a care plan for seasonal mood and sleep problems, and many provide CBT for SAD. A 2015 study of people with recurrent SAD found that CBT for SAD had durable effects even two winters after treatment ended.

General guidelines for coping with seasonal affective disorder (SAD) include:

  • Stay connected, even during social distancing (e.g., plan regular phone calls or video chats with loved ones).
  • Be kind to yourself. Create a manageable schedule of things to look forward to. Put mood-boosting activities on the calendar from December until March.
  • Eat a balanced diet and mindfully manage carbohydrate cravings.
  • Use caffeine wisely or eliminate it if it has negative effects.
  • Try to maintain a regular sleep schedule.
  • Practice relaxation techniques.
  • Spend time outside (e.g., plan a walking meeting, lunchtime walk, or outdoor chores) in the morning and at midday.