In most cases, SAD symptoms start in the late fall or early winter and go away during the spring and summer; this is known as winter-pattern SAD or winter depression. Some people may experience depressive episodes during the spring and summer months; this is called summer-pattern SAD or summer depression and is less common.
What are the signs and symptoms of SAD?
SAD is not considered a separate disorder but is a type of depression characterized by its recurrent seasonal pattern, with symptoms lasting about 4 to 5 months per year. Therefore, the signs and symptoms of SAD include those associated with major depression, and some specific symptoms that differ for winter-pattern and summer-pattern SAD. Not every person with SAD will experience all of the symptoms listed below.
Symptoms of major depression may include:
Feeling depressed most of the day, nearly every day
Losing interest in activities you once enjoyed
Experiencing changes in appetite or weight
Having problems with sleep
Feeling sluggish or agitated
Having low energy
Feeling hopeless or worthless
Having difficulty concentrating
Having frequent thoughts of death or suicide
For winter-pattern SAD, additional specific symptoms may include:
Overeating, particularly with a craving for carbohydrates
Social withdrawal (feeling like “hibernating”)
If you think you may be suffering from SAD, talk to your health care provider or a mental health specialist about your concerns. They may have you fill out specific questionnaires to determine if your symptoms meet the criteria for SAD.
How is SAD treated?
Treatments are available that can help many people with SAD. They fall into four main categories that may be used alone or in combination:
Talk to your health care provider about which treatment, or combination of treatments, is best for you. For tips for talking with your health care provider, refer to the NIMH fact sheet, Taking Control of Your Mental Health: Tips for Talking With Your Health Care Provider.
Since the 1980s, light therapy has been a mainstay for the treatment of SAD. It aims to expose people with SAD to a bright light every day to make up for the diminished natural sunshine in the darker months.
For this treatment, the person sits in front of a very bright light box (10,000 lux) every day for about 30 to 45 minutes, usually first thing in the morning, from fall to spring. The light boxes, which are about 20 times brighter than ordinary indoor light, filter out the potentially damaging UV light, making this a safe treatment for most. However, people with certain eye diseases or people taking certain medications that increase sensitivity to sunlight may need to use alternative treatments or use light therapy under medical supervision.
With regard to light therapy, I bought full spectrum lights for my aunt’s living room which we used year ’round. She passed away some years ago from the disease, but never displayed any aggression. So, I believe that the lights did not cause any problems and may have helped her through her SAD periods.
Because many people with SAD often have vitamin D deficiency, nutritional supplements of vitamin D may help improve their symptoms. However, studies testing whether vitamin D is effective in SAD treatment have produced mixed findings, with some results indicating that it is as effective as light therapy but others detecting no effect.