Is seasonal affective disorder (SAD) considered depression? If so, should I be treated for it year-round even though it comes and goes?
Seasonal affective disorder, or SAD, is a form of depression that primarily affects people during the fall and winter months when there is less daylight, particularly in locations farther from the equator. This lack of light can disturb the internal clock and may lead to feelings of depression. The change in seasons can also influence the body’s melatonin and serotonin — natural substances that play a role in sleep timing and mood. When combined, these factors may lead to SAD.
More than just feeling blue or lacking energy on cold winter days, SAD involves persistent, pervasive symptoms of depression. Those symptoms may include feeling sad, angry or easily irritable most of the day nearly every day; lack of interest in activities once enjoyed; difficulty concentrating; persistent tiredness; lack of energy; and, in some cases, feeling that life isn’t worth living or having suicidal thoughts.
People with SAD often feel tired and sleep more than usual. They also tend to crave carbohydrates and eat more, which often causes weight gain. Symptoms may get worse as winter progresses.
The good news is that there are several effective treatments for SAD. Light box therapy is particularly useful. Starting light box therapy in early autumn may help prevent SAD from developing during the winter months. Light boxes or light therapy lamps mimic outdoor light by emitting a broad-spectrum ultraviolet light. Sitting in front of a lamp for a mere 30 minutes a day can have great benefits. Many people use light boxes while drinking their morning coffee, reading the news or having breakfast.
Light therapy lamps are widely available and range in price. It’s recommended you use the lamp at the beginning of day, with the unit 12 to 24 inches away. The intensity of the light box is recorded in lux, which is a measure of the amount of light you receive at a specific distance from a light source. The recommended intensity of the light is typically 10,000 lux.
Medication may also be part of treatment. The antidepressant medication bupropion has been approved by the U.S. Food and Drug Administration for the prevention of SAD. Other antidepressant medications may be effective, as well. These medications can be helpful for people who have a pattern of SAD and know that they are predisposed to developing it. If you’ve had SAD in the past, starting to take medication in early fall before the days get significantly shorter may prevent or reduce symptoms.
Psychotherapy has also been found to be effective. The treatment that has shown the most success for prevention and treatment is cognitive behavioral therapy for SAD, or CBT-SAD.
There are also many self-care steps you can take all year long that may help reduce your risk. These include getting regular exercise, maintaining healthy sleep habits including a predictable sleep/wake cycle, eating a healthy diet and limiting the amount of sugary foods you consume.
Going outside on sunny days can also make a difference. When the sun reflects off the snowy ground, clear days can be brilliantly bright. Exposure to that natural sunlight can help ease symptoms.
If you’ve been diagnosed with SAD in the past or you suspect you have it, talk to your doctor about prevention and treatment options. Even if it can’t always be prevented, there are treatments available that can help you successfully manage your symptoms. And because this condition is seasonal, symptoms will begin to fade as daylight lengthens in the spring.
William B. Leasure, M.D.
Dr. William Leasure is a psychiatrist at Mayo Clinic, Minnesota.