It is true that the weather can affect your mood, something you might be able to relate to from personal experience. This may hit home if you have ever had a hard time pulling yourself out of bed on a rainy day. But is this just a normal case of the rainy day blues or is there something larger at play? In terms of feeling down or struggling to find motivation on a rainy day, yes, many people have experienced that at least once or twice before. However, if you are affected by a change in weather for the duration of a season, you may actually have Seasonal Affective Disorder (SAD). SAD is a clinical condition that affects about half a million Americans and is classified as a subtype of Major Depressive Disorder in the Diagnostic and Statistical Manual of Mental Disorders. The disorder is comprised of two subtypes— fall and winter SAD in addition to spring and summer SAD. SAD is often described as “an extreme lethargy and sadness” that persists for the duration of a season (Psych Central). Therefore, it is a fact that the weather can actually cause clinical depression and not just a minor case of the blues that should be ignored.
Because SAD is a subtype of depression, a lot of symptoms of major depressive disorder are present in people who have SAD (Mayo Clinic). Some of these symptoms include low energy, feelings of worthlessness or hopelessness, changes in appetite or weight, sleep disturbances, feeling depressed most of the day almost every day of the week, loss of interest in activities once enjoyed, difficulty concentrating, feeling agitated or sluggish, and frequent thoughts of suicide or death. The specific type of SAD, either fall and winter or spring and summer, is accompanied by additional distinct symptoms that serve to differentiate the two subtypes from one another.
People with fall and winter SAD also experience low energy and irritability, however they are typically hypersensitive to rejection; they have difficulty getting along with others; they oversleep; have heavy “leaden” feelings in their arms or legs creating a sensation similar to trying to move your limbs while trudging through molasses; they experience changes in appetite, especially carbohydrate cravings; and weight gain. Spring and summer SAD is less common than fall and winter SAD, but people who experience spring and summer SAD may have difficulty sleeping, also known as insomnia; poor appetite; weight loss; and agitation or anxiety.
Important to note are the changes in mood that people with bipolar disorder may experience. During the fall and winter, it is more likely for someone with bipolar disorder to experience depression. However, spring and summer can be a time of mania or hypomania.
How do people develop SAD? The specific causes remain unknown, but evidence strongly suggests that it is triggered by changes in the availability of sunlight through several avenues (Mayo Clinic). These include your personal biological clock, or circadian rhythm; vitamin D; and the hormones serotonin and melatonin. A lack of sunlight during the fall and winter months may disturb your body’s biological clock and trigger depression. Decreased sunlight also results in a dearth of vitamin D3 because we are not being exposed to ultraviolet B rays, contributing to symptoms of depression (Yahoo News). Reduced sunlight can also decrease the levels of serotonin, a chemical in the brain that affects mood, therefore causing depression (Mayo Clinic). Additionally, seasonal changes can thwart the amount of melatonin in your body, and as a result can affect your mood and patterns of sleep. People living in cloudier regions or at a higher altitude have also been noted to be at greater risk for developing SAD (Yahoo News).
Want to learn how to cure yourself of SAD? Check out 10 Ways to Kick Your Winter Blues to find out how!