What is Seasonal Affective Disorder (SAD)?

It’s not unusual to notice your mood changing with the seasons. Different times of the year bring their own stressors, and not everyone enjoys cold temperatures or the hot sun.  

Mood changes aren’t always a reason for alarm, but if you’re experiencing major depressive episodes during a specific time of the year, you may be living with seasonal affective disorder (SAD).

What is seasonal affective disorder?

Seasonal affective disorder (SAD) is a clinical term for a pattern of major depressive or manic episodes during a specific season. For many people, SAD is linked to the fall and winter months, but some people experience SAD during spring and summer.

According to the Diagnostic and Statistical Manual of Mental Disorders, 5^th edition, text revision (DSM-5-TR), SAD is actually a specifier of major depressive disorder (MDD) or bipolar disorder. The DSM-5-TR is a guidebook published by the American Psychiatric Association to help diagnose mental health conditions.

Winter-pattern vs. summer-pattern SAD

SAD is most common during the winter months, but it can happen during summer months, too.  

Winter-pattern SAD usually begins in the fall when there’s less daylight. Symptoms sometimes worsen as daylight hours shorten, then improve during spring and summer. With winter-pattern SAD, you may feel a little better on bright, sunny days or as temperatures warm.

Summer-pattern SAD worsens when daylight hours increase and temperatures rise. Unlike winter-pattern SAD, summer-pattern SAD improves during fall and winter.  

SAD vs. the “winter blues”

The “winter blues” are not the same as SAD.  

SAD is a depressive disorder. It’s a condition that can negatively impact your quality of life and your ability to function at home, work, or school.  

The “winter blues” aren’t a formal medical condition, but they do describe a shared experience of low mood among many people when the days grow shorter and the weather gets colder.  

The big differences between the winter blues and SAD are the severity and duration of your symptoms.  

If you’re experiencing the winter blues, you may have days when you feel unexplained sadness or a loss of motivation, but these feelings are often temporary. They don’t usually interrupt your daily routine or stop you from doing important tasks.  

In SAD, a low mood or lack of motivation is there almost all day, every day for a persistent period of time (e.g., 2 weeks or more). Symptoms can be severe enough to keep you from regular activities.

Symptoms of seasonal depression

Seasonal depression can affect your emotions, thoughts, and how your body feels.  

In SAD, depression meets the DSM-5-TR criteria of a major depressive episode, which lasts at least 2 weeks. Major depressive episodes feature daily depressed mood or a loss of interest or pleasure toward almost all activities.

You may feel sad all the time, hopeless, or empty during seasonal depression. You might burst into tears if someone asks you what’s wrong. Many people feel no motivation and can’t bring themselves to take on basic tasks like showering or brushing their teeth.

Other symptoms seen in major depressive episodes include:

• Significant weight loss or gain
• Sleeping too much or too little
• Chronic fatigue or low energy
• Brain fog or trouble making decisions
• Inappropriate feelings of worthlessness or guilt
• Irritability
• Restlessness or agitation
• Physical aches and pains, like headaches, crapms, or digestive upset
• Social withdrawal
• Thoughts of death or suicide

Symptoms associated with winter-pattern SAD include:

• Social withdrawal
• Overearing
• Oversleeping

Symptoms associated with summer-pattern SAD include:

• anxiety
• restlessness and agitation
• trouble sleeping
• weight loss
• aggression

Not everyone living with SAD experiences the same symptoms or the same symptom severity.  

If any of these sound familiar, take a free depression assessment or explore online depression treatment with a Talkiatry psychiatrist.

{{BLOG_AD}}

What causes SAD, and who is most at risk?

The exact causes of SAD aren’t clear. Researchers believe seasonal changes in daylight exposure can affect your body’s internal clock, brain chemicals, and mood. For some people, these changes may be enough to trigger a major depressive episode or a potential manic episode in bipolar disorder.

Daylight changes are just one factor that might contribute to SAD. Genetics can also play a role. SAD can run in families, and certain genetic factors may make you more sensitive to seasonal changes.  

Due to individual genetics and biology, some people may also be more likely than others to develop depressive disorders overall.

People at the highest risk for SAD include:

• women
• people living in higher northern lattitudes
• people living with other mental health disorders
• people who have a family history of SAD or other mood disorders

How is SAD diagnosed?

A psychiatrist can diagnose a mood disorder and help determine if there’s a seasonal pattern related to the mood episodes.

“SAD” is a general term that describes a seasonal depression cycle in MDD or bipolar disorder.  

Doctors use the DSM-5-TR to help match your symptoms with an underlying condition first. Then they look at when depressive episodes happen most often. If depressive episodes happen predictably during a specific season over multiple years, your doctor may assign a seasonal pattern “specifier” to your diagnosis.

Specifiers in the DSM-5-TR are descriptive terms that help add clarity and details to a diagnosis.

If you’re living with bipolar disorder, the official DSM-5-TR diagnosis for SAD would be “bipolar disorder with a seasonal pattern.” If you’ve been diagnosed with major depressive disorder, the diagnosis would be “major depressive disorder with a seasonal pattern.”

To meet the DSM-5-TR criteria for SAD, symptoms must follow a predictable seasonal pattern for at least two consecutive years. Seasonal depressive episodes must significantly outnumber nonseasonal episodes over the course of a person’s lifetime.

Treatment options for SAD

SAD is treatable. Your doctor will recommend treatment based on your diagnosis, symptom severity, and personal preferences. Many treatment plans for SAD involve more than one type of therapy. Treatment plans may also include medication.  

Therapy (CBT-SAD)

Traditional therapies for depression, like talk therapy, can also be used to treat SAD. Cognitive behavioral therapy (CBT) is a type of talk therapy that takes place under the guidance of a qualified mental health professional.

Your therapist works with you to identify unhelpful thought and behavior patterns that contribute to seasonal depression. You then learn how to replace those unhelpful patterns with more beneficial ones.

Medication

Seasonal depression medications are some of the same medications used for other types of major depressive episodes. Doctors may prescribe antidepressants, for example, to help regulate chemical signaling in your brain and improve your mood.  

Bupropion XL is an antidepressant approved specifically for SAD in adults with a history of the condition. Psychiatrists often recommend starting it in the fall before your symptoms begin and then continuing it through the winter.  

Timing depends on your individual symptom history, but clinical trials have shown that starting early may help prevent seasonal depression episodes.  

Depending on your diagnosis, your treatment plan may also include additional medications for bipolar disorder or MDD.

Light therapy

Light therapy is primarily used to treat winter-pattern SAD, and can be used alongside talk therapy or medication. It involves sitting in front of a very bright light box daily for around 30-45 minutes. The exact amount of time you spend doing light therapy will depend on the light device and your treatment plan.

Light therapy can help regulate a person’s internal clock, or circadian rhythm, during months when natural daylight is short.

When to talk to a psychiatrist about seasonal depression

You don’t have to go through multiple years of seasonal depression before talking to a doctor. While establishing a seasonal pattern is important, depression can be treated right away.

Talk to a psychiatrist any time you’ve been experiencing persistent symptoms of low mood, lack of motivation, or negative thoughts.  

Getting started with Talkiatry

Talkiatry is a national psychiatry practice that makes it easier to get care from doctors who listen. Start by answering a few questions online, then get matched with a psychiatrist based on your needs. From there, you can schedule a visit, often within days, and meet with your provider from home.  

First visits are 60 minutes, so there's time to talk through what's going on and build a treatment plan together. Talkiatry is in-network with most major insurers, and you can check your coverage during the free online assessment.  

Take our free online assessment

Frequently asked questions

Is seasonal depression a real diagnosis or just the winter blues?

Yes. Seasonal depression is a official diagnosis in the DSM-5. It’s not the same as the winter blues.

When should I start treatment if my depression comes back every winter?

When you start seasonal depression treatment will depend on your history of symptoms. Starting treatment early may help prevent seasonal depression. Your doctor can help identify the right treatment plan and timeline for you.  

Do SAD lamps actually work, and what kind should I use?

Light therapy is an effective treatment for SAD. Research suggests bright light devices are the most effective, but individual use depends on your diagnosis and treatment plan.

Can you have seasonal depression in the summer?

Yes. Seasonal depression can happen during any season. In many cases, treatment will look similar regardless of the season.  

Does insurance cover treatment for seasonal affective disorder?

Treatment coverage for SAD will depend on your individual insurance carrier and plan.  

Medical disclaimer and sources

The information in this article is for informational and educational purposes only and should never be substituted for medical advice, diagnosis, or treatment. If you or someone you know may be in danger, call 911 or the National Suicide and Crisis Lifeline at 988 right away.

Sources:

1. Alshaya DS. (2022). Genetic and epigenetic factors associated with depression: An updated overview. https://pmc.ncbi.nlm.nih.gov/articles/PMC9232544
2. Chen Z-W, et al. (2024). Treatment measures for seasonal affective disorder: A network meta-analysis. https://www.sciencedirect.com/science/article/abs/pii/S0165032724000399
3. Huecker MR, et al. (2024). Bupropion. https://www.ncbi.nlm.nih.gov/books/NBK470212
4. Modell JG, et al. (2005). Seasonal affective disorder and its prevention by anticipatory treatment with bupropion XL. https://www.biologicalpsychiatryjournal.com/article/S0006-3223(05)00910-8/abstract
5. Munir S, et al. (2024). Seasonal affective disorder. https://www.ncbi.nlm.nih.gov/books/NBK568745
6. easonal affective disorder. (2023). https://www.nimh.nih.gov/health/publications/seasonal-affective-disorder
7. Seasonal affective disorder and complementary health approaches: What the science says. (2019). https://www.nccih.nih.gov/health/providers/digest/seasonal-affective-disorder-and-complementary-health-approaches-science
8. Seasonal affective disorder: More than the winter blues. (2023). https://www.apa.org/topics/depression/seasonal-affective-disorder

‍

‍