December is Seasonal Affective Disorder Awareness Month. Seasonal depression, or SAD, is a type of depression triggered by the change of seasons and most commonly begins in late fall and goes through the winter. Symptoms often include feelings of sadness, lack of energy, loss of interest in usual activities, oversleeping and sometimes leads to weight gain. About 5% of adults in the U.S. experience SAD. It tends to start in young adulthood (usually between the ages of 18 and 30) and SAD affects females more than men, though researchers aren’t sure why. About 10% to 20% of people in America may get a milder form of the winter blues.
Researchers are unsure exactly what causes seasonal depression. Some theories include:
Biological clock change: Your internal, biological clock regulates your mood, sleep and hormones. This clock shifts with less sunlight in the winter months and causes you to feel you’re out of line with the daily schedule you’ve been accustomed to. This in turn can lead to difficulty adjusting to changes in daylight length.
Brain chemical imbalance: Brain chemicals called neurotransmitters send communications between nerves. These chemicals include serotonin, which contributes to feelings of happiness. Since sunlight helps regulate serotonin, a lack of sunlight in the winter can make the situation worse. Individuals at risk of SAD may already have less serotonin activity.
Vitamin D deficiency: Studies have found that serotonin levels get a boost from vitamin D. Since sunlight helps produce vitamin D, less sun in the winter can lead to a vitamin D deficiency and that change can affect your serotonin level and your mood.
Negative thoughts: People with SAD often have stress, anxiety and negative thoughts about the winter. Researchers aren’t sure if these negative thoughts are a cause or effect of seasonal depression but this theory is being researched.
While there is no blood test or scan to diagnose seasonal depression, your provider may recommend testing to rule out other conditions that cause similar symptoms, including testing your thyroid to make sure it’s functioning properly or other hormonal imbalances.
There is a lot of research being done on the treatment of SAD. Recent studies have found that ensuring adequate amounts of the B vitamins, such as vitamin B6, thiamin, and folic acid, may enhance mood. Medications used to treat depression (antidepressants) can be effective for SAD when used alone or in combination with talk therapy. Antidepressants work by changing how the brain produces or uses certain chemicals involved in mood or stress.
If you or someone you know is showing symptoms of SAD, talk to a health care provider or a mental health specialist about your concerns. They may have you fill out a questionnaire to determine if your symptoms meet the criteria for SAD. To be diagnosed with SAD, a person must meet the specific criteria.
WebMd offers suggestions for treatments and prevention from experiencing SAD including: light therapy, time outdoors, and exercise and provides suggestions for when to call your doctor: https://www.webmd.com/depression/seasonal-affective-disorder