Try This
Winter blues? Try blue light therapy to lighten up your winters, boost mood, energy and shine out seasonal affective disorder.
Seasonal Affective Disorder
By Cleveland Clinic Wellness Editors 
Published 1/18/2010 
Decrease text size Increase text size

Winter Blues? You May Have Seasonal Affective Disorder

Shorter days, frigid temperatures, bulky clothing, dry skin — it’s easy to feel like the winter season is working against us! But if you find yourself sleeping and eating more than usual, gaining weight, craving carbohydrates and withdrawing from social events and friends, you might be more than unhappy about the season — you might have SAD, or seasonal affective disorder. SAD is a type of depression triggered by the change in season that recurs annually, usually toward the end of the fall through the beginning of spring. A less common type of SAD can occur in the spring or summer.

Who gets SAD?
According to the American Academy of Family Physicians (AAFP), about 4 to 6 percent of Americans may have winter depression. Another 10 to 20 percent may have mild SAD.

SAD is four times more common in women than in men. The main age of onset is between 18 and 30, although some children and teenagers can get SAD. Your chance of getting SAD diminishes as you age.

SAD is also more common the farther north you go. It’s estimated that as many as 20 to 30 percent of the population living in the middle to northern latitudes of the United States may experience at least some SAD symptoms, according to the University of Washington Counseling Center.

Other studies show that it’s more prevalent in North America than in Europe and your chances of developing SAD increase if you have a family member with it.

How to know if you have SAD
Core symptoms of SAD, says Scott M. Bea, PsyD, a clinical psychologist at the Cleveland Clinic, include increased sleep and appetite, weight gain and carbohydrate cravings. Other symptoms may include fatigue, irritability, avoidance of friends and social events, an inability to concentrate or be productive and, in some cases, thoughts of suicide. SAD symptoms appear only during a specific season, most commonly the winter, and don’t manifest for the rest of the year. It’s usually diagnosed after occurring at least two years in a row.

The truth is, it’s not uncommon to feel a little sluggish and down in the winter. It’s chilly and dark, and the holidays can make some people irritable. Cold weather also generally makes us hungrier, with a craving for richer, heavier foods than we typically eat in the summer. So how do you know if you just have the winter blahs or a more serious disorder like SAD?

“You’re going to see a real change in your functions. You might have a sense of hopelessness, a loss of energy — you find yourself withdrawing from social situations, oversleeping, hibernating,” Dr. Bea says. “Also, a lot of people complain about winter blues, but SAD is a real depression that’s occurring the same time every year.”

When diagnosing SAD, other factors — like dreading the holidays, marking a depressing winter anniversary or experiencing seasonal job loss — need to be carefully considered, because your symptoms could be caused by something other than the change of season.

According to Kelly Rohan, PhD, an associate professor of psychology at the University of Vermont, the first signs of the disorder will vary from person to person, but they generally come on gradually and progress into a full-blown depression over a matter of several weeks.

What causes SAD?
Although there are no conclusive answers to what causes SAD, there are several prevailing theories that have to do with the decrease in sunlight.

  • The most common theory says that as the seasons change, there is a shift in our internal biological clock, or circadian rhythm, due partly to changes in sunlight pattern. The later sunrise and earlier dawn cause our biological clocks to be out of step with our daily schedules, resulting in a host of SAD-related symptoms.
  • Another theory is related to melatonin levels. According to Mental Health America, melatonin, a hormone that induces sleep, is produced at increased levels in the dark. Therefore, when the days are shorter and darker, the production of this hormone increases, causing an increase in sleep time and possibly depression.
  • The last theory says that levels of serotonin, a neurotransmitter that enhances mood, decrease with the decrease in sunlight.

How to prevent and treat SAD
Aside from flying south for the winter (wouldn’t that be nice!), you can prevent and/or treat SAD symptoms with a variety of proven methods. Dr. Rohan says that at the very first sign of the onset of symptoms you should seek professional help. “Prevention of a couple of symptoms is much easier than treating a full-blown SAD episode,” she says. The three most common treatments include:

Light therapy — which usually consists of exposure to 10,000 lux of cool-white or full-spectrum fluorescent light with ultraviolet rays filtered out — for about 30 minutes a day first thing in the morning is recommended as the first line of treatment. Studies show that it’s about 75 to 80 percent effective in treating SAD symptoms.

But some people may need a slight adjustment to length and time of day of exposure. “It’s not a one-size-fits-all prescription,” warns Dr. Rohan, who strongly recommends trying light therapy, or any of the therapies outlined below, in conjunction with a trained professional, to figure out the right combination. She advises that there are possible side effects for light therapy that can include headaches, eye strain, insomnia, mania and hypomania.

Antidepressants can be prescribed in place of light therapy or in conjunction with it. A 2006 study reported in the American Psychiatric Journal found that light therapy and the antidepressant drug fluoxetine (Prozac) are equally effective treatment options for patients with SAD, although light therapy was found to work faster and have fewer side effects. 

Cognitive behavioral therapy (CBT) has also been found to be as effective as light therapy. Dr. Rohan, who conducted studies on the efficacy of CBT, found that 12 sessions spread over six weeks can help SAD patients learn and develop coping skills, such as identifying negative thoughts and reframing them or identifying winter activities to take part in instead of hibernating. She found that CBT treatment, alone or in conjunction with light therapy, was associated with a lower depression occurrence and less severe symptoms in subsequent winters, compared to light treatment therapy alone.

Some other less studied or unproven treatments include:

  • Dawn simulation therapy utilizes a device that simulates a natural summer dawn in the winter by gradually increasing ambient light while the user sleeps.
  • Negative air ions, which many believe to have mood-lifting properties, are produced by a generator that fills the air and subsequently can improve SAD symptoms.
  • Vitamin D is reduced when our exposure to the sun is reduced, and vitamin D deficiency has been linked to depression. Therefore, proponents say, increased vitamin D supplements may help treat SAD.

As with many conditions, a generally healthy lifestyle can help reduce symptoms. If you think you may be experiencing SAD, you could benefit from regular exercise, a healthy diet rich in fruits and vegetables and stress management through yoga or meditation.

Get Your Daily Tip
Start living healthier with our FREE daily wellness tips!