Whole Health
January/February 2008

The SAD Truth

Feeling down and can’t shake it? The light of day could be just what you need to chase away those winter blahs.

By Kara Douglass Thom

Ever notice when clouds stick around longer than normal—say, from a stalled weather system—that the extended period without the sun leaves you craving its rays? You find yourself slightly anxious, eager to curl up in a ball and nap, perhaps a titch crabby with your loved ones. This may sound like PMS, but this mood disorder has another acronym: SAD, for seasonal affective disorder.

According to the American Psychiatric Association, symptoms of SAD include fatigue, social withdrawal, decreased motivation to pursue normal activities, cravings for carbohydrates, and—no surprise—weight gain. More women than men typically develop symptoms; and if you have a family history of SAD or depression, you’re at higher risk.

Although SAD can manifest year-round, the majority of cases occur in the winter (January and February are the SADest months) and especially to those living farther north. But SAD can just as easily affect people who work long hours in buildings without windows.
Most of us experience minor episodes of SAD. You might chalk it up to “winter blues,” but it doesn’t affect your routine as you know it. Sometimes, though, it alters your disposition enough to warrant intervention.

Shawn Strathe, 34, of Minneapolis was first diagnosed with SAD in 1993 after moving to Minnesota from Oklahoma to start college. “I didn’t see the sun as I was either in class or working all the time,” says Shawn. “I was really down. I figured it was a combination of things, but I felt worse as winter set in and realized I needed professional help.”

Douglas Jacobs, MD, associate clinical professor of psychiatry at Harvard Medical School and president and CEO of Screening for Mental Health, the largest nationwide screening program for mental disorders, likens the difference between mild and more-intense episodes of SAD to the difference between a virus and bacterial infection. “With a virus you may have all the symptoms of an underlying infection, but it tends to go away within a week or two without an antibiotic,” he says. If the symptoms of SAD don’t diminish within a few weeks, it’s more like a bacterial infection that won’t disappear without a prescription. SAD requires some adjustments and interventions, Dr. Jacobs says, but ultimately the best treatment is the change of the season.

Shawn gave antidepressants a try, but she hated the side effects. Daily doses of prescribed artificial light proved more beneficial, but the time commitment was an inconvenience. It wasn’t until 2000 when she starting running outside during the winter that she felt the most relief. “Exercising outside in the air with some light totally worked for me,” she says, adding that her brain lets her know if she’s missed so much as two days without an outside run. “My body tells me too, but the brain is much louder about it.”

So what’s up with this intense connection to the sun? It helps to understand our circadian rhythms, which tick to our own biological clock. Our clock works off of cues (a rooster crowing, the smell of coffee brewing, and, yes, the sun rising) that guide our physiology, such as sleep patterns, hunger, cell regeneration, and hormone production. This system helps keep our internal clock in sync with the external environment, so if one of these cues gets disrupted, our biological clock can go haywire.

In the case of SAD, the lack of light causes biochemical imbalances in the brain, which trigger symptoms. One such imbalance occurs because the hormone melatonin (sometimes recommended as a sleep aid) increases in our body the more we’re exposed to darkness.

Unlike bears, however, we humans can’t hibernate all winter long. A better way to cope is through light therapy. A 1993 study found that using a specific type of fluorescent light at the first onset of symptoms prevented the mood disorder from escalating. Today smaller, more-convenient light-emitting diode (LED) lamps can offset symptoms of SAD. The LED wavelength is identical to that of sunshine (without harmful ultraviolet rays). You simply position the light slightly above your face—keeping your eyes open—similar to the angle sunlight would fall. The exposure should last between 15 minutes and an hour in the morning. Current research is studying whether blue light (versus white light) can better relieve symptoms.

You might have thought your days of worshipping the sun were over, but if you’re prone to seasonal affective disorder, be sure to pay your respects. “It’s a real disorder—not an imaginary one,” says Dr. Jacobs. “There are corrective actions.” And for some of us, that action is as simple as “seeing the light.”