As the holidays wind down and the weather changes from wet and nasty to cold and icy, many people discover that they are spending more time inside. During short days, they get relatively little sun exposure.
This is the time of year many people feel sad, even if they don’t normally suffer from depression. In fact, the winter blues are technically known as seasonal affective disorder, or SAD for short.
Symptoms of SAD include depression, lethargy, low energy, irritability, oversleeping and craving carbohydrates. The typical pattern is for these symptoms to start showing up in late fall or early winter. They normally disappear in late spring or early summer.
The leading hypothesis is that seasonal affective disorder is a reaction to a shortened period of daylight. It seems to be more common in northern areas where days get really short in the winter, with estimates ranging from 9.7 percent prevalence in New Hampshire to 1.4 percent in Florida (Psychiatry, January 2005).
Short of taking a winterlong vacation in Hawaii or some other sunny, warm island, there is no way to supply missing daylight. Psychiatrists have been debating the value of light therapy for years. Some think that it is impossible to replicate the benefits of sun exposure. Others have prescribed light boxes to provide artificial sunshine.
One analysis of randomized controlled trials published in the American Journal of Psychiatry (April 2005) found that bright-light therapy could help reduce symptoms of depression about as well as antidepressant medications.
A double-blind controlled study conducted in Canada during the winter compared the antidepressant fluoxetine (Prozac) with light therapy. The authors found that the light treatment worked faster, was as effective as the antidepressant and produced fewer side effects than fluoxetine (American Journal of Psychiatry, May 2006).
If you can’t start your day with an hourlong walk outside, you might consider a light box to provide up to 10,000 lux of light. Usually a half-hour of treatment is adequate for about 50 percent of those who suffer from SAD. Some light-box brands available include NatureBright, Carex Day-Light and Northern Light.
Another potential contributor to SAD is a lack of vitamin D. During the winter, blood levels of this nutrient drop, especially in northern latitudes. Although high-quality research is scarce, one meta-analysis concluded that vitamin D supplementation at 800 IUs per day or more is comparable to antidepressant medications (Nutrients, April 11, 2014).
There is more information about depression, including SAD, in our Guide to Dealing With Depression. It includes a discussion of nondrug treatments as well as a comparison of many antidepressant medications. Anyone who would like a copy, please send $3 in check or money order with a long (No. 10), stamped (71 cents), self-addressed envelope to: Graedons’ People’s Pharmacy, No. E-7, P.O. Box 52027, Durham, NC 27717-2027. It also can be downloaded for $2 from our website: peoplespharmacy.com.
Other strategies include regular exercise and fish oil. A long time ago, grandmothers in northern countries used to dose children with cod liver oil. No one subjected to this treatment enjoyed it, but the combination of vitamin D and omega-3 fatty acids in the fish oil seems to have had beneficial effects (Expert Opinion on Investigational Drugs, December 2013).
Joe Graedon is a pharmacologist. Teresa Graedon holds a doctorate in medical anthropology and is a nutrition expert. Their syndicated radio show can be heard on public radio. In their column, Joe and Teresa Graedon answer letters from readers. Write to them via their website: PeoplesPharmacy.com.