Checkup on Health: Go outside to cure the winter blues
It’s the middle of winter, and we’re surrounded by cloudy skies and cold weather. It’s no wonder that some people just want to hibernate indoors. Many of us experience the “winter blahs” – a depressed mood that lifts when the sun comes out in spring. A small percentage actually have a recognized psychiatric condition called seasonal affective disorder (SAD), characterized by symptoms of depression during the dark, winter months.
Most of us don’t consider how much brighter it is outside than inside unless we are taking photographs indoors and realize we need a flash, or we are hunting for our sunglasses for a trip to the beach. There are many examples of plants and animals with sensitivities to such variation in light intensity. Think of roosters who crow at dawn or houseplants that won’t flower unless they’re near the proper window. It should come as no surprise that humans also need certain light requirements to thrive.
About the author
Dr. Servis is a professor of clinical psychiatry and vice chair of the UC Davis Department of Psychiatry and Behavioral Sciences.
In addition to mood disturbances, people with SAD tend to feel extremely fatigued in the winter months and need more sleep than usual. They also commonly crave carbohydrates and put on weight, often shedding the extra pounds in spring.
The disorder affects about 2 to 5 percent of people in the U.S, and interestingly, is even more common in northern regions of the globe, where daylight hours are shorter. Some sufferers of other kinds of emotional disorders, such as premenstrual syndrome and bulimia nervosa, a eating disorder, also show seasonal variations. Such patterns may go unrecognized: improvement in the spring is often attributed to treatment success, and worsening symptoms in the fall or winter may be regarded as random recurrences.
Light exposure helps, natural or not
Not surprisingly, the most effective treatment found for SAD is to increase exposure to light. People with mild to moderate symptoms benefit from more time outdoors in the winter, perhaps with a daily walk or eating lunch on a park bench. Another way to increase daily exposure is to adjust sleep schedules. People can take full advantage of available daylight by awakening earlier in the morning.
For those who aren’t helped by these measures or who have more severe symptoms, talk with a doctor. The next step is artificial light therapy, which has been found to be as effective as medications in helping this disorder.
The standard medical treatment for SAD is a TV-sized light box, containing fluorescent bulbs behind a protective filter. These boxes, which cost in the range of $200 to $500 (and are sometimes available to rent), are covered by an increasing number of insurance companies. They emit 2,500 to 10,000 lux (a term used to quantify brightness), which is about equivalent to the outdoor light of dawn or dusk. Illumination in homes and offices is about 500 lux.
Treatment for SAD typically involves daily sessions in front of a light box for a period of 15 minutes to 2 hours. Some studies indicate that light therapy in the morning is more effective than at other times of the day. Most people begin to feel benefits after only a few days. Antidepressant medications, by comparison, often takes a few weeks for improvement to be noted.
Some SAD sufferers are not good candidates for light therapy. Although no evidence of eye damage has been reported, it is of potential concern. Those with certain eye conditions such as macular degeneration or a diabetes-related eye problem should avoid it.
Some people report headache, nausea, dizziness and excitability after light therapy. Usually such side effects are mild and short-lived, and patients can continue treatment. Mood swings may also develop, but can be avoided with careful dosing and timing of therapy with the help of a physician.
When light doesn't help
For those who don’t find relief with either more time outdoors or in front of a light box, counseling and medications can also be effective, sometimes in combination with light therapy. Medications in the class of selective serotonin reuptake inhibitors (SSRIs), such as Prozac, seem to work best.
Several studies are finding other interesting correlations between light and health. Light therapy has also shown promising results for depression without discernable seasonal patterns, premenstrual syndrome and eating disorders. It may also play a role in helping those with altered circadian rhythms due to shift-work, jet lag and disrupted sleep cycles.
For most people, the solution to winter blues is no further than out the front door. A daily walk outdoors can not only make us feel better mentally, but provide a myriad of other health advantages we can benefit from throughout the year.