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What Is Seasonal Affective Disorder?

mental healthwinterdepressionSADSeasonal Affective DisorderNewsletterHealth & Wellness • 3 min read • Jan 18, 2017 12:00:00 AM • Written by: Kat Smith

If you tend to feel down in the winter, there may be more to what you’re experiencing than simple holiday blues. Seasonal Affective Disorder, cleverly known as SAD, may be behind your winter doldrums, and it is a condition to take just as seriously as any other type of depression. SAD occurs because exposure to sunlight can directly affect hormone production, which can in turn throw your brain chemistry off balance and cause telltale symptoms of depression in the late fall through the early spring. This article will offer a closer look at what happens to your body and brain when faced with a lack of daylight hours, and will provide some helpful solutions to keeping SAD at bay throughout the course of the winter season.

How sunlight affects your body

Though Seasonal Affective Disorder is still being researched and some causes of this phenomenon are unclear, it is known that sunlight can have a strong impact on certain bodily functions. Perhaps most importantly, levels of serotonin (a chemical responsible for maintaining mood balance) are prone to dip down in the winter. Some individuals have about 5% more serotonin transporter proteins in the wintertime, leaving less serotonin available at key receptor sites, and making one more prone to depression. Additionally, reduced sun exposure can limit vitamin D production in the body and boost melatonin production, causing you to feel zapped of energy and frequently tired. Because the length of the day will be significantly shortened in areas further from the equator, those who live further north (or south, in the Southern Hemisphere) will be more greatly affected by SAD.

What symptoms SAD will cause

SAD can manifest with typical depression symptoms, such as feelings of helplessness or worthlessness, suicidal thoughts, mood swings or agitation, sluggishness, loss of interest in regular activities, and changes in appetite. More specific to Seasonal Affective Disorder are symptoms including carbohydrate cravings, low energy, hypersomnia, overeating, and social withdrawal. With SAD, symptoms will generally worsen throughout the winter and subside in the spring and summer. Typically, individuals with SAD will experience symptoms every winter for a period of at least two years. Those who are already prone to depression or individuals with a family history of mood disorders will be at the highest risk for Seasonal Affective Disorder.

How to control SAD


Treatment for SAD is not unlike general depression treatment. Ideally, individuals experiencing SAD will reach out for help from a family doctor or general practitioner, who may refer patients to a therapist for talk therapy. Medication—SSRIs in particular—can be successful as part of SAD treatment, but it is important to carefully monitor symptoms with these medications and avoid suddenly stopping medication when the winter season ends. Even if depression symptoms have subsided, halting medication rather than gradually dosing down under a physician’s care can have harmful side effects. Another type of therapy to consider is light therapy, which uses a specially designed light that mimics natural sunlight without heavy UV exposure. SAD light boxes are available to purchase without a prescription, and can help you to regulate vitamin D, serotonin, and melatonin levels to achieve a more ideal balance in brain chemistry. When using a light box, be sure to follow the manufacturer’s instructions carefully while also discussing light therapy with your doctor to ensure the proper timing and effectiveness of your therapy.

SAD does not have to bring you down this winter. Even when you cannot muster the energy to leave the house, MeMD is here for you with 24/7 on-demand medical exams and talk therapy visits in as few as 24 hours. You can have a complete consultation via web cam so that you can get the treatment, medication and guidance you need to overcome SAD for a more productive winter season.

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Kat Smith