It's that time of year: The summer sunshine is dwindling, and we're waking to black skies in the morning and driving home in growing darkness after work.
If you start to feel a little blue as the winter approaches and your time in the sunshine fades, you are not alone. But how do you know if you are just lamenting the end of summer fun, or if your "winter blues" may require professional treatment?
Seasonal Affective Disorder (SAD) is a type of Major Depressive Disorder that occurs in a seasonal pattern. SAD occurs in about 3% of people, and more often in women, according to Linda Carpenter, MD, chief of Butler Hospital's Mood Disorders Program and Neuromodulation Clinic.
Carpenter says symptoms vary from one person to the next, but may include:
- An onset of symptoms related to a change in the seasons. While SAD is most commonly experienced in the fall and winter when daylight decreases, some patients will experience the reverse and the onset of a depressive episode in spring or summer.
- Diminished joy in things that were once pleasurable
- Changes in energy and sleep patterns. Instead of experiencing depression with insomnia, people with SAD tend to have hypersomnia, or increased sleeping, with more napping during the day. "It's almost like hibernating," Carpenter says.
- Changes in the ability to function or think clearly
- Changes in eating habits. "We tend to see a pattern of oversleeping and overeating," Carpenter says, adding that people may crave carbohydrates specifically.
- A negative mood or pessimistic and hopeless thoughts
If you think you may be struggling with SAD, contact your doctor or mental health professional. Either may prescribe one of a range of medications shown to be effective in treating SAD. Many boost the level of serotonin in the brain, which is thought to contribute to feelings of well-being and happiness.
Additionally, "There's a medicine that has been shown to prevent SAD before it even starts in individuals who are vulnerable," Carpenter says.
If you prefer alternatives, your physician may suggest phototherapy, or exposure to artificial light, which has been shown to be beneficial in treating SAD. Not any light source will do, though. You need to purchase one that emits the appropriate amount of "lux," or illuminance, recommended by your physician. Newer light sources use LED technology, and may be more portable and more comfortable. Talk therapy with a licensed therapist can also be effective.
Lawrence H. Price, MD, vice president of Medical Affairs and medical director at Butler and professor of psychiatry and human behavior at The Alpert Medical School of Brown University, says there are many theories behind the causes of SAD, but the most widely accepted one is that the amount of sunlight people are exposed to diminishes in fall/winter.
"If you look at prevalence of major depression at different latitudes, research shows it's pretty common in northern latitudes, like Maine, and much less common in southern latitudes, like Florida," he says.
Sunlight affects an area of the brain responsible for such functions as sleep, heart rate and blood pressure, appetite, weight regulation, and sexual function.
"Good evidence exists that light box treatment, which is 20 times brighter than normal indoor light, is very effective. Light boxes are commercially sold and easy to purchase; however, a person should not start light therapy without consulting their physician or psychiatrist since it can worsen certain eye conditions," Price says, stressing that although artificial sunlight from light boxes is effective, nothing works better than natural, outdoor light.
So how long does it take to feel better once spring rolls around and the days get longer? "In general, mood improvement tends to correlate with the lengthening of daylight," says Price. "So, most people are feeling substantially better by the time spring is in full bloom."