Seasonal Affective Disorder (SAD) is a depression that occurs in people at the same time each year–usually in winter, hence the nickname “winter blues.” It became an official diagnosis in 1984 when Dr. Norman Rosenthal of the National Institute for Mental Health published a study that started with a man named Herb Kern. Herb was a research engineer who got severely depressed every winter. Herb was sure it was due to the lack of sunlight and was willing to be studied to prove it.
Sure enough, Dr. Rosenthal’s lightbox treatment helped. Herb felt much better in a few days. Dr. Rosenthal ran a study and showed that the lightbox really worked.
SAD primarily affects women. When it occurs in winter, there are often behavioral and psychological changes, such as alterations of sleep and appetite or even feelings of hopelessness and worthlessness. In Alaska and Finland, where the sun is nearly gone for months at a time, SAD affects almost 10% of people. In sunny Florida, that rate is 1.5%.
In addition to light exposure, there may be other factors that affect SAD including inherited genes, fish consumption, melatonin, serotonin, and personality traits.
There is not much we can do to change winter, but there are things that can help reduce SAD.
A trusted treatment is increased exposure to light. The most economical way to do that is to spend more time outdoors during daylight. There are also artificial lights. There are lightbox treatments (30-60 minutes each) and many types of SAD electric lights for home use. You can buy a lightbox without a prescription. Most health insurance plans do not cover the cost. Increased physical exercise also helps. The light and physical exercise can be combined in a daily walk.
Dawn simulation has also been shown to be effective. Dawn simulation is the scheduling of light to come on gradually starting about one hour before your awakening. These are available as wake-up lights, sunrise alarm clocks, natural light alarm clocks and various other names. The idea is to imitate a natural sunrise.
Medications including anti-depressants may also be used. Speak with your health care provider about what’s best for you.