For many, the changing of the seasons means cozy dark evenings of winter and enjoying holiday light displays. But perhaps for you, the shortening of the days signals a time when you feel down, sad or withdrawn. You may notice that you sleep more and eat more, and even gain weight. You may feel a lack of energy, or have problems with your memory. You may cry at unexpected times. You may feel hopeless and even lose the will to live or think of suicide. If these symptoms interfere with everyday life, you may have Seasonal Affective Disorder (SAD).
SAD is a type of depression that is related to, or worsened by, the change of the seasons. Most people with a seasonal pattern of depression feel worse in the fall and winter, but some experience it in the spring and summer.
SAD can be a part of Major Depressive Disorder or Bipolar Disorder. Depression is a complex neurobiological illness involving many of the chemicals that transmit signals in the brain and nervous system. These signals allow parts of the brain to communicate with each other, but in depression, the emotional and cognitive circuits in the brain are impaired.
Another system that is impaired in depression is the circadian rhythm system, which regulates the daily variations of hormone secretion in the body. This system, which receives input through the eyes and is sensitive to light, is responsible for telling the body to feel tired, hungry and energetic at certain times each day. Genetic and biological abnormalities of the circadian rhythm system are present in depression and may be responsible for the disturbances in sleep, appetite and energy that people with SAD experience.
Many treatments are helpful for SAD. If depression is severe and you are feeling hopeless, you should see your primary care doctor or a psychiatrist. If you are having thoughts of suicide, seek medical attention immediately. In addition to professional assistance, family and friends can be a good source of support during this difficult time.
If you experience these emotional downturns in winter, whether mild or severe, a healthy lifestyle can improve how you feel. Eating a diet with plenty of lean sources of protein, complex carbohydrates such as whole wheat bread, whole wheat pasta, and other grains, fresh fruit and vegetables and few sweets and high-fat foods will improve energy. Exercising at least several times a week can improve energy and reduce weight gain. Sleeping at the same time each night, getting up the same time each morning and limiting any naps to 20-30 minutes in the mid-afternoon can improve the quality of sleep. Eliminating recreational drug use and limiting alcohol use to one to two drinks, no more than twice a week can improve sleep, appetite and energy.
A very effective treatment for SAD that may be recommended by your physician is light therapy. The use of light much brighter than usual indoor lighting can mimic sunlight and re-set the circadian clock. Use of a light box may improve mood, energy, sleep habits, and appetite within seven to 10 days. Be aware that bright light may worsen certain eye or skin conditions, so its a good idea to check with your physician before using a light box. Side effects can be irritability, too much energy, and insomnia.
Medications, too, can be used to treat SAD. Antidepressants such as serotonin re-uptake inhibitors, serotonin-norepinephrine re-uptake inhibitors, or norepinephrine-dopamine re-uptake inhibitors may be used. Use of any medication will depend on your symptoms and your medical history.
Psychotherapy is another effective treatment for SAD. Structured therapies that focus on the regulation of sleep cycle and interactions with others throughout the day have been particularly helpful for SAD. In addition to helping with symptoms of SAD, therapy can improve motivation to make healthy lifestyle changes.
Explore further: Depression, suicide and the workplace - Q&A