Every year, as the days grow shorter, millions of Americans (an estimated 6 percent of the U.S. population) find that their mood is darkening and their energy is disappearing along with the light. Until the days are significantly longer again in the spring, they have many of the symptoms of depression, along with excessive eating and sleeping and a craving for sugar and carbohydrates.
This condition is known as seasonal affective disorder (SAD) or seasonal clinical depression. It’s thought that SAD might be caused by an increase in melatonin, a sleep-related hormone. Melatonin production increases in the dark.
The key factor in diagnosing SAD is its seasonality. If you only suffer depressive symptoms in late fall to early spring, for at least two years, chances are that you have SAD.
Seek medical advice for SAD if your functioning is impaired significantly (difficulty getting to work on time, concentrating or completing tasks); you have significant feelings of depression (feeling sad, crying spells, negative thoughts, feeling guilty or hopeless); or your physical functioning changes drastically (greater need for sleep, a drastic decrease in energy).
I know of one man who moved from a northern climate to Hawaii to treat his SAD. You’ll probably want to treat yours in a more traditional manner, with bright light therapy or antidepressants (SSRIs, typically). Bright light therapy has been shown to suppress the brain’s production of melatonin. Exercise and a healthy diet are often another part of a SAD treatment program.
Apparently, animals can also suffer from SAD. A recent study found that hamsters housed in winter-like light conditions were more likely to exhibit symptoms of depression and anxiety. (I do wonder how you can tell when a hamster’s depressed. Maybe they stop using their little exercise wheel …) Future studies will look at whether hamster SAD improves with antidepressants.
Perhaps nature meant for us all to hibernate in the winter.
For more information about SAD, check out these resources:
The Seasonal Affective Disorder Association
Winter Blues: Everything You Need to Know to Beat Seasonal Affective Disorder (revised edition) by Norman E. Rosenthal, M.D.
Published On: November 21, 2005