Seasonal affective disorder (SAD)
If you need to talk to someone about your mental health, call Beyond Blue on 1300 22 4636.
Key facts
- Seasonal affective disorder is a type of depression that comes at certain times of the year, usually in winter.
- Seasonal affective disorder is very rare in Australia.
- Symptoms can include lack of energy, overeating and sleeping too much.
- It is thought to be caused by the changes in light exposure in different seasons.
- Treatment includes antidepressant medicines, light therapy, vitamin D and counselling.
What is seasonal affective disorder?
Seasonal affective disorder is a type of depression that comes and goes according to the season. People with seasonal affective disorder experience symptoms of depression or mania at roughly the same time each year.
Seasonal affective disorder usually develops in autumn and winter and then disappears in spring and summer. In some people, the symptoms develop in spring and early summer.
What are the symptoms of seasonal affective disorder?
Symptoms of seasonal affective disorder in winter include:
- low mood
- sleeping too much
- lack of energy and fatigue
- craving carbohydrates and sugary foods
- gaining weight
- losing interest in normal activities
Symptoms of seasonal affective disorder in summer include:
- low mood
- trouble sleeping
- lack of energy
- not feeling hungry
- losing weight
- feeling agitated and anxious
- losing interest in normal activities
Symptoms usually start out mild and get worse as the season progresses. When the season changes, people normally become well again.
People with a mental health disorder might find that their symptoms change at different times of the year. For example, some people with depression or bipolar disorder find that their symptoms of depression get worse in different seasons.
CHECK YOUR SYMPTOMS — Use the Symptom Checker and find out if you need to seek medical help.
What causes seasonal affective disorder?
The cause of seasonal affective disorder is not clear. It is thought to be caused by changes in light exposure, which lead to changes to the body’s circadian rhythms (its 'body clock'). At different times of the year, the body produces different amounts of melatonin and serotonin, which affect mood.
You are at higher risk of having seasonal affective disorder if you:
- are female
- are young
- live further from the equator
- have a family history of seasonal affective disorder or depression
When should I see my doctor?
Seasonal affective disorder is very rare in Australia. If you have symptoms that don’t go away and are affecting your everyday life, it’s important to see a doctor. They can help you build a mental health care plan and refer you to a mental health professional if needed.
ASK YOUR DOCTOR — Preparing for an appointment? Use the Question Builder for general tips on what to ask your GP or specialist.
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How is seasonal affective disorder diagnosed?
Seasonal affective disorder can be difficult to diagnose, as it can be confused with other mental health conditions. You may not be diagnosed until you have experienced the same symptoms during winter for at least 2 years.
Your doctor ask questions about how you feel and how long you have been feeling that way. Your doctor may refer you for tests to rule out medical conditions that could be causing your symptoms.
How is seasonal affective disorder treated?
The first step of treating seasonal affective disorder is to talk to a doctor or a mental health professional.
Once you are diagnosed, treatment options can include:
- light therapy, also known as phototherapy. This involves exposure to a bright light after waking in the morning. It can affect your brain chemistry and relieve your symptoms relatively quickly.
- medicines — such as antidepressants (in severe cases)
- psychotherapy — such as cognitive behaviour therapy (CBT)
- vitamin D supplements
It’s a good idea to make your house as light as possible during autumn and winter, and to sit close to windows as often as you can.
Getting outside as much as possible and exercising regularly can also help lift your mood and reduce symptoms of seasonal affective disorder.
Resources and support
There are Australian organisations that offer help and resources for people with depression.
- Wayahead has further information on seasonal affective disorder.
- Beyond Blue has a guide to what works for depression in young people and other resources.
- For advice and to get connected to local mental health services, call Head to Healthon 1800 595 212. Check the operating times.
If you need to speak with someone, you can call theses helplines for general mental health support.
- healthdirect helpline - 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.
- Sane — talk to a mental health professional on 1800 187 263
- Beyond Blue — 1300 22 4636 for phone counselling or chat online
- Suicide Call Back Service (for anyone thinking about suicide) — 1300 659 467
- Lifeline (for anyone having a personal crisis) — call 13 11 14 or chat online
Do you prefer to read in languages other than English?
- SANE offers a range of support services including a free translating and interpreting service available on 131 450.
- Transcultural Mental Health Centre has many resources about wellbeing and mental health in different languages.
- Beyond blue has translated mental health resources.
Looking for information for Aboriginal and/or Torres Strait Islander people?
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Last reviewed: February 2024
