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What Is SAD and How Common Is It?
During the darker days of winter, 10 to 20% of Americans suffer from mild depression or fatigue. For many, this condition, known as the “winter blues,” is a normal response to less sunlight. But approximately 5% of Americans experience a stronger reaction, a clinical form of depression called seasonal affective disorder (SAD).SAD is a type of depression that is related to changes in seasons. The formal diagnostic classification of SAD from The Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR) is recurrent Major Depressive Disorder with a Seasonal Pattern. Although recurrent summer depressive episodes can happen, these are much less common than the pattern of winter depression.
Since SAD is typically linked so close to wintertime, it is not surprising that SAD is much more common in the northern states, where the seasonal change is most pronounced compared to the southern states. In the U.S., for example, winter depression is relatively rare in Floria but affects nearly 1 in 10 people in New England. By spring and summer, when we see more daylight and the temperatures start to warm, most people recover completely from winter SAD.
What Causes SAD?
There is still ongoing debates among scientists on the precise causes of SAD, but certain factors seem to play a role:- Circadian Rhythms. Our body’s internal clocks, or circadian rhythms, rely on two important things to run smoothly: routine and sunlight – both are disrupted during the winter months, causing feelings of depression.
- Vitamin D Deficiency. Natural sunlight is a primary source of vitamin D, a vital nutrient essential to overall mental and physical health. People with vitamin D deficiency are more vulnerable to developing SAD during winter.
- Increased Melatonin. A hormone the body makes in response to darkness, melatonin can increase with longer nights, causing lethargy, drowsiness, and altered sleep patterns that affect mood.
- Decreased Seratonin. A lack of sunlight can cause a decrease in serotonin – the body’s “feel good” chemical in the brain responsible for mood.
Typical Symptoms
According to the National Institute of Mental Health, the symptoms of SAD vary but can include many symptoms similar to major depression, such as:- Feeling of persistent sadness
- Loss of interest or pleasure in activities you used to enjoy
- Changes in weight and appetite, usually eating more, craving carbohydrates
- Difficulty sleeping or oversleeping
- Irritability or restlessness
- Fatigue and decreased energy
- Difficulty concentrating, remembering details, and making decisions
- Feeling hopeless, worthless, guilty
- Withdrawal from social connections
- Thoughts of death or suicide
Getting Help If You or a Loved One is Facing Emotional Distress
Symptoms of depression may start out mild and become more severe as the season progresses. If you experience any of the symptoms mentioned above and are having difficulty functioning at school or work, or if your symptoms interfere with your ability to interact with your family or others, or you feel hopeless and have thoughts of suicide, consult your healthcare provider immediately, who can help with a diagnosis and treatment plan, or seek help at the closest emergency room. You can also dial 988 to reach the 988 Suicide and Crisis Lifeline or visit https://988lifeline.org/.
How Can You Beat the Winter Blues?
- Exercise. In general, exercising regularly and finding ways to manage your stress is a good idea. Even though it may be cold or dark outside, it’s important to stay active socially, so make an effort to meet friends for dinner or attend a class or group activity. When you are feeling down, sometimes the most difficult thing to do is simply to get up and move. Yet, exercise has been consistently shown as one of the most effective ways to address depression in general.
- Diet. When it comes to health, including mental health, eating healthfully matters. People struggling with SAD can find themselves more drawn to sugary food. Although eating sugar can promote some immediate relief from sadness, this can compound the problems as a diet excess in sugar can make depression worse. Nutritionists recommend eating more foods with B vitamins, such as fruits, leafy green vegetables, whole-grain bread, fish, and chicken, to fight off depression.
- Get More Sunlight. For some people, increased exposure to sunlight can help improve symptoms of SAD. For example, spend time outside or arrange your home or office so you can be exposed to a window during the day. There are, however, risks associated with too much UV light exposure. Please consult with a healthcare professional about the risks and benefits.
Treatment Options
- Light Therapy. Another option to help you cope with living with less light is light therapy. Light therapy involves sitting in front of a lightbox for about thirty minutes every morning. The box’s light mimics natural outdoor light and is much brighter than ordinary indoor lighting. Studies have shown that light therapy relieves SAD symptoms for about 70% of patients after a few weeks of treatment, with some seeing improvement even sooner. Lightboxes are not regulated, so do your research and look for a lightbox that provides white light -- as opposed to blue or "full-spectrum" -- with 10,000 lux of illumination and a broad diffuser screen that filters out UV rays. It’s best to check with your doctor before starting light therapy to get their recommendation.
- Antidepressant Medications. If light therapy alone doesn’t work and your symptoms turn toward depression, talk to your doctor to see if you might benefit from an antidepressant. It can take a few weeks to feel the positive effects, and you may have to try a few different medications to find the one that works best for you, but if your symptoms are interfering with your quality of life, this may be an effective solution.
- Talk Therapy. Growing evidence suggests that cognitive-behavioral therapy (CBT), or talk therapy, can help patients who have SAD. CBT focuses on developing skills to improve coping with the seasons. A CBT therapist will work with you to foster both behavioral (doing) skills and cognitive (thinking) skills. The behavioral skills involve identifying, scheduling, and doing pleasurable, engaging activities every day in the winter. Over time, these behaviors are meant to counteract the down, lethargic mood and the tendency to give in to the “hibernation” urges that are so common in SAD.
