Now that the Christmas tree is composting and radio stations have shelved that cheery holiday music until next winter, let's get real with some rewriting: 'Tis the season to be melancholy.
You know the feeling: You're more tired these days, maybe anxious or moody. Cocooning with some leftover Christmas cookies or other sweet and high-carb fare sounds better than hanging with the crowd. Your sexual appetite may be on a diet, or even fasting. It's harder to get out of bed, and when you do, your mood resembles the landscape you see -- cold, dark, and nasty.
That's the problem: The gloom caused by Mother Nature each winter in much of the country is biologically felt to some degree by an estimated one in four of us -- usually starting around October and then magically ending by April with spring's thaw. For most people, it manifests as winter doldrums, the "I-can't-wait-for-winter-to-end" feeling that produce mild but manageable sluggishness and food cravings. But about 11 million Americans have a more severe form of winter depression -- seasonal affective disorder, the aptly acronymed SAD that is typically diagnosed after at least two consecutive years of more intense symptoms.
"While a person with winter doldrums may have difficulty waking up or getting out of bed at times, someone with seasonal affective disorder can't get to work on time," says Michael Terman, PhD, director of the Winter Depression Program at New York Psychiatric Institute and Columbia University Medical Center. "With the doldrums, it's in the norm to gain up to 5 or 6 pounds over the winter, but with full-blown SAD, weight gain can be far more than that."
Either way, it stems from the same cause: Sensitivity to the lack of sunlight that results from winter's "shorter" days and disrupts our circadian rhythm, or internal body clock. The degree of this sensitivity, and resulting winter depression severity, largely stems from some combination of other factors -- your geography, genetics, and individual brain chemistry.
With SAD, the lack of sunlight causes the brain to work overtime producing melatonin, the hormone that regulates your body clock and sleep patterns and a hormone that has been linked to depression. That's why all things considered, the farther north from the equator you live, the greater the risk you'll have some degree of winter depression. Only about 1% of Florida residents have some winter-specific discomfort or depression, compared to about half of those living in uppermost parts of the U.S. or in southern Canada.
"The body clock takes its cue from sunlight, especially that in the morning. But as you get up into the northern-tier states, there's a 4½ hour delay in sunrise in mid-winter versus the summer"; in the middle portion of the U.S., there's a two-hour difference," Terman tells WebMD. "This difference is enough to affect circadian rhythm timing and throw the body clock out of sync."
The solution is to get as much sunlight as possible. Light enters the eye, which activates a body clock system that is similar to what controls seasonal breeding and hibernation in animals, says psychiatrist Daniel F. Kripke, MD, who conducted the world's first controlled study of bright light therapy for depression in 1981. This system is connected to the brain's appetite hardwiring, which might explain why you may have more food cravings in winter.
"But getting enough natural sunlight can be difficult now in many parts of the country," says Kripke, professor of psychiatry at the University of California, San Diego. "When people travel to and come home from work or school, it's dark outside because of the shorter days."
And because it's also cold, they're less likely to venture outdoors and get direct sunlight exposure, which keeps the body clock in sync. "Standing by a window doesn't do it," Kripke tells WebMD. "It's like why you use different camera settings when taking photographs outdoors and indoors. And with the angle and darkened glass of many car windshields, your retina doesn't get enough sunlight while you're driving, even when it's sunny."
Regular indoor lighting also has no effect, no matter how bright it is. To compensate, artificial "sunbox" lights with special fluorescent tubes that mimic the sun's beneficial rays are available and are considered the go-to treatment for those with any level of winter depression. "You might think those with winter doldrums might need less exposure to bright light therapy than people with SAD, but both groups benefit from the same amount," says Terman.
That's about 30 minutes of exposure done first thing in the morning. "Timing is very important, and by administering it first thing in the morning, you keep your body clock on its springtime cycle during the winter, and that's how the depressive symptoms are lifted." These sunboxes can be placed on a desk or table while you eat breakfast or work.
Terman has also done research suggesting that ions in the air -- those invisible particles that can help improve mood -- also affect winter depression. When SAD patients were exposed to high levels of negative ions for 30 minutes, their depression eased after just a few weeks. "Natural concentrations of negative ions are highest at the seashore, by the pounding surf, or right after a spring thunderstorm," he says. "That's why many people report a spontaneous elevation in mood from being at the beach." While commercially sold negative ionizers produce lower levels than what he used in his experiments, they may help some people.
Antidepressants are also beneficial, especially when used in conjunction with light therapy. "But my reading is that antidepressants by themselves are not as effective as light therapy by itself," says Kripke. He notes in a 1998 study that light therapy brought relief to many patients within one week, while antidepressants took about eight weeks.
In addition to sunlight -- or more specifically, the lack of it -- the cold temperatures of this mean season may also play a role. "There is some evidence that people with a higher tolerance to cold tend to be less depressed than those who are more susceptible to cold," says Charles Raison, MD, of Emory University's Mind-Body Program and an assistant professor of psychiatry and behavioral sciences at its medical school.
"We also know there's a greater tendency toward depressive symptoms immediately following a viral illness," he tells WebMD. "When you get a cold, your immune system is stirred up in a way that it's a risk factor for depression." And you'll note, it is the cold and flu season.
So if you've got the winter blues -- especially in a deep shade -- here's your excuse to cash in those frequent flyer miles: "Sometimes, something as simple as taking a week or two vacation to Florida or somewhere sunny during January or February can make a really big difference," says Raison.