Colder temperatures and shorter days got you down? For many of us, the lack of sunlight at specific points of the year can trigger the "winter blues." It's normal to feel a little sluggish or less upbeat. But if these feelings are more intense, linger for longer than two weeks or persist year after year, they might be seasonal affective disorder (SAD) symptoms. How can you distinguish between temporary weather woes and symptoms of SAD? Experts explain everything you need to know.
What is seasonal affective disorder?
"Seasonal Affective Disorder is a type of depression that occurs at certain times of the year, typically during the winter months when daylight hours are shorter," says Sanam Hafeez, PsyD, a clinical neuropsychologist and founder and director of Comprehend the Mind.
SAD isn't recognized as a standalone diagnosis in the current edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR), explains Abrah Sprung, PhD, licensed clinical psychologist and founder of Parkview Counseling. "Instead, it is categorized as a specifier under Major Depressive Disorder (MDD) and Bipolar Disorder, 'with seasonal pattern' added to describe mood disorders that follow a seasonal course," she says.
Common symptoms of seasonal affective disorder
There are two types of SAD: winter SAD and summer SAD. "Winter-pattern SAD, also known as winter depression, is the most common form," says Hafeez. "On the other hand, summer-pattern SAD occurs during the spring or summer months and is less common."
Symptoms of winter-pattern seasonal affective disorder:
Symptoms of summer-pattern seasonal affective disorder:
What causes seasonal affective disorder?
While the exact cause of SAD isn't fully understood, experts suspect it occurs due to changes in light exposure (such as during daylight savings time or a change in seasons). "These changes in light exposure affect your circadian rhythms, melatonin levels and serotonin production, which all impact sleep and mood regulation, potentially resulting in SAD," says Tamar Z. Kahane PsyD, clinical psychologist, founder and clinical director of The Kahane Center, LLC.
Less sunlight decreases the production of serotonin, a brain chemical linked to mood regulation, and increases the production of melatonin, which can make you feel groggy.
Seasonal affective disorder is more common in women
According to Sprung, SAD affects about five percent of adults in the United States, and women are diagnosed four times more often than men. "While anyone can develop SAD, it is more common in younger adults and people who live in regions with long winters or limited sunlight, such as northern latitudes," she says.
When to seek help for SAD
While Kahane says it's normal and very common to experience mild mood changes due to seasonal changes, it's important to talk to your doctor when symptoms persist for weeks and interfere with your daily functioning.
You'll also want to talk to someone who specializes in mental health disorders. "A psychologist or psychiatrist can help differentiate between SAD and other mental health conditions, such as major depressive disorder, which may require different treatment approaches," says Hafeez.
The most common treatments for people with SAD include light therapy (sitting in front of a lightbox or near bright light), supplementing with vitamin D (the "sunshine vitamin"), talk therapy and/or medication, according to the National Institute of Mental Health. (Learn more about how to treat SAD here.)