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Seasonal Affective Disorder

Season affective disorder (SAD) is a type of depression that occurs when an individual experiences significant mood changes as the seasons change.

Cloudy Day

What is seasonal affective disorder (SAD) (NIH, n.d.)?

  • SAD is a type of depression that occurs when an individual experiences significant mood changes as the seasons change

  • Majority of individuals with SAD experience SAD symptoms starting in late fall or early winter and start to feel improvement as spring and summer approach

    • This is known as “winter-pattern SAD” or “winter blues”

  • A less common form of SAD is when individuals experience the depressive episodes during spring and summer and start to feel improvement as winter approaches

    • This is known as “summer-pattern SAD” or “summer depression”

  • An estimated 10 million Americans experience SAD per year

    • Women are four times more likely to experience SAD than men (Targum & Rosenthal, 2008)



What are the symptoms of SAD (American Psychiatric Association, 2022)?

  • SAD symptoms are the same for both forms of SAD, summer and winter

  • Symptoms of SAD can vary from mild to severe and often mimic symptoms of depression

  • Common SAD symptoms include:

    • Fatigue, even with good sleep

    • Weight gain due to overeating

    • Feelings of sadness or having a depressed mood

    • Change in appetite

      • Typically, cravings of carbohydrates

    • Change in sleep

      • Winter SAD – sleeping too much

      • Summer SAD – sleeping too little

    • Decreased energy

    • Increased fidgeting (e.g., inability to sit still, pacing, foot tapping, etc.)

    • Feelings of worthlessness or guilt

    • Difficulty concentrating or making decisions

    • Thoughts of death or suicide

  • SAD symptoms can start at any age but typically begin to occur between 18 and 30 years of age



Why does SAD occur (Barclay Friends, 2022)?

  • Though scientists are unsure of the exact cause of SAD, scientists do know that certain factors play a role

  •  Factors that contribute to the onset of SAD are:

    • Circadian rhythms – the lack of sunshine in winter months disrupts our body’s natural internal clock (circadian rhythms), which triggers depression

    • Decreased serotonin – serotonin, known as the “feel good chemical” in our brain, is responsible for our mood

      • When natural light decreases, our serotonin levels do as well

    • Increased melatonin – melatonin is a hormone made by the body in response to darkness; as darkness increases, so does our bodies production of melatonin, causing drowsiness, lethargy, and sleep pattern disruption

    • Decreased vitamin D – vitamin D is a nutrient that is essential to our overall mental and physical health; as our main source of vitamin D comes from the sun, when sunlight decreases, our intake of vitamin D does as well

      • Seniors are particularly vulnerable to vitamin D deficiencies putting them at higher risk to develop SAD during the winter months



How can I cope with SAD (Cohut, 2017)?

  • There are a variety of coping mechanisms that can be utilized during your season of SAD

  • Dr. Norman Ronsenthal, who originally pushed for SAD to be recognized as a valid disorder, recommends the following:

    • Obtain a SAD light box

      • Make sure the light box generates a minimum of 10,000 lux

      • Ensure the light box was made to treat SAD, depression, or other mood disorders

        • Do NOT use light boxes for skin treatments

      • Tips for using the lightbox:

        • Sit in front of the lightbox for 20-90 minutes per day

        • You will get the most benefit when using the lightbox in the morning

        • Make sure the light falls on your eyes – it helps to have the light at eye level or higher

        • Make sure the light is at least 2 feet away from you

    • Other ways to get through the season of SAD are:

      • Eat healthy

        • Individuals with SAD tend to eat more carbohydrates, sweets, and starchy foods

        • Overeating is a common symptom in the “season of lows”

        • Eat food high in Vitamin D and omega-3 fatty acids

        • Some recommended foods are eggs, mushrooms, fruits, vegetables, salmon, chia seeds, flaxseed, and soybeans

      • Stay active

        • Research shows that even as little as 1 hour of exercise per week counteracts depression, though it is recommended you get at least 30 minutes of exercise per day

        • Staying active also regulates your circadian rhythm, which is the main culprit of SAD

      • Do not isolate yourself inside

        • Especially in the cold months, it can be tempting to barricade yourself indoors – this will only make your symptoms worse

        • Notice details about your natural surroundings

          • Find things that make you feel happy or sociable

      • Cognitive behavioral therapy and medications

        • These are often used to help manage SAD symptoms

      • Cut back on alcohol consumption

        • Though some are prone to overeating, many people’s alcohol consumption increases during the season of SAD

          • As alcohol is a depressant, this makes depressive symptoms more severe

          • Cutting back on alcohol may alleviate some of your symptoms



SAD lights and mental health (Campbell et al., 2017)

  • SAD lights are also referred to as bright light therapy (BLT) which can be used to treat mental health disorders other than SAD, such as depression, eating disorders, and adult attention-deficit hyperactivity disorder (ADHD)

  • BLT is an appealing treatment option, or addition to treatment, as it is noninvasive, has very minimal side effects, and is effective, even for children and pregnant women

  • Depression

    • BLT has been shown to be effective in major depressive disorder (MDD), antepartum and postpartum depression, as well as bipolar depression

    • Meta-analysis studies show that individuals experience greater treatment outcomes when BLT is used in conjunction with medication management

      • Bipolar Depression

        • Studies show that lithium and antidepressants in addition to BLT is an extremely effective treatment approach

          • Improvement often begins to occur in as little as a week

        • Research data suggests that incorporating BLT plays a significant role in the treatment of bipolar depression, especially in patients who are treatment-resistant

    • Eating disorders

      • Though BLT in eating disorders still needs to be studied further, the few studies that do exist have shown a benefit in incorporating BLT into eating disorder treatment

        • Researchers believe that the increased carbohydrate cravings that result from changes in our circadian rhythms play a significant role in the increased binge eating episodes during fall and winter seasons in individuals with binge eating disorder or bulimia nervosa

          • Studies show that though body mass index (BMI) neither increases or decreases after incorporating BLT, there are significant reports of a decrease in depression and carbohydrate cravings

        • BLT in anorexia nervosa treatment has yet to be investigated further as well, but researchers do know that BLT improves depressive symptoms, leading to improvements in treatment

    • Adult ADHD

      • Adults with ADHD often experience depressive moods, sleep and wake difficulties, and maintaining arousal, in addition to the typical ADHD symptoms

        • Multiple studies show that utilizing BLT in adult ADHD treatment improves circadian rhythms, leading to improved moods, improved sleep and wake cycles, and an improvement in ADHD symptoms such as focus, impulsivity, and executive functioning

  • The benefits of BLT in the treatment of mental health disorders are still being investigated. What researchers do know at this point is that BLT has potential to be beneficial in the treatment of a wide array of psychiatric disorders


Crisis Resources:

  • NAMI HelpLine

  • NAMI Crisis Text Line

    • Text NAMI to 741-741

  • COPE (Hennepin County)

    • Adult: 612-596-1223

    • Child: 612-348-2233

  • Ramsey County

    • Adult: 651-266-7900

    • Child: 651-266-7878

  • Text Connect (Crisis counseling via text)

    • Text “HOME” to 741741








American Psychiatric Association. (2022). Seasonal affective disorder (SAD).


Barclay Friends. (2022). Shedding light on seasonal affective disorder.,+News,+%26+Events&utm_medium=ppc&hsa_mt=b&hsa_ad=581079630939&hsa_net=adwords&hsa_src=g&hsa_kw=sad%20depression&hsa_tgt=kwd-847130576763&hsa_cam=12828062778&hsa_acc=2158485384&hsa_ver=3&hsa_grp=130456470182&gclid=EAIaIQobChMI29CA-PnY-gIV6SZMCh3QagQ5EAAYASAAEgJq2_D_BwE


Campbell, P. D., Miller, A. M., & Woesner, M. E. (2017). Bright light therapy: Seasonal affective disorder and beyond. The Einstein journal of biology and medicine: EJBM, 32, E13–E25.


Cohut, M. (2017). How can you cope with seasonal affective disorder? Medical News Today.

National Institute of Mental Health (NIH). (n.d.). Seasonal affective disorder.


Targum, S. D., & Rosenthal, N. (May 2008). Seasonal affective disorder. Psychiatry (Edgmont) 5(5):31-3. PMID: 19727250; PMCID: PMC2686645.

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