As the days get shorter and the temperatures go down, the feeling of just wanting to crawl on the bed and eating some comfort carbohydrates is very real for many people.
The idea of "winter blues" is not just something to be liquidated, experts say. It can be a sign of a true medical condition known as seasonal affective disorder, or SAD.
"This is a real thing, it's legitimate," said Dr. Jennifer Ashton, a correspondent OB-GYN medical expert and ABC News. "It has many mood characteristics that overlap with those of major depression".
SAD is defined as a type of depression that comes and goes with the seasons, generally from late autumn and early winter and leaving during spring and summer , according to the National Institutes of Health (NIH).
SAD can also occur with the change of season in the summer, but it is much less common than the winter episodes, notes NIH.
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Depression is diagnosed four times more often in women than in men and occurs more frequently in younger adults, says the NIH.
Symptoms of SAD include less energy, a need for more sleep and a change in appetite, particularly an increase in the desire for carbohydrate-rich foods, Ashton says.
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While there are many theories, the exact cause of SAD has not been identified. Researchers believe this may be caused by factors such as changes in the biological clock or circadian rhythm and changes in serotonin or serotonin levels in the brain and genetics, adds Ashton.
The good news is that there are ways to reduce the effects of SAD.
4 ways to help treat SAD
1. Light therapy: The daily exposure to artificial light and intense can replace the fewer hours of sunshine in the winter and autumn months. Be sure to consult a mental health professional before buying a lamp, Ashton advises.
The NIH recommends 20 to 60 minutes per day of exposure to 10,000 lux of cold white fluorescent light.
Ashton noted that the use of a tanning bed is not a safe option for light therapy.
2. Drugs: There are selective serotonin reuptake inhibitors (SSRIs) that are used to treat SAD, according to the NIH.
Individuals with SAD may need to try different antidepressant medications before finding what improves symptoms without causing side effects, NIH notes.
3. Diet: Ashton recommends following a diet rich in green leafy vegetables and even dark chocolate.
When choosing carbohydrates, be sure to skip those that contain white sugar, he adds.
4. Professional Aid: Cognitive behavioral therapy (CBT) and behavioral activation are two types of therapy identified by NIH as effective for SAD.