What is seasonal affective disorder (SAD)? 

Seasonal affective disorder (SAD) is a type of depression that you experience during particular seasons or times of year. Depression is a low mood that lasts for a long time, and affects your everyday life. 

If you have SAD, you’ll experience depression during some seasons in particular, or because of certain types of weather. 

“It’s like having your own portable black cloud.” 

It’s common to be affected by changing seasons and weather, or to have times of year when you feel more or less comfortable. For example, you might find that your mood or energy levels drop when it gets colder or warmer, or notice changes in your sleeping or eating patterns. 

But if your feelings are interfering with your day to day life, it could be a sign that you have depression – and if they keep coming back at the same time of year, doctors might call this seasonal affective disorder or ‘seasonal depression’. 

“In the colder, winter months I start to feel sluggish and down, it’s harder to keep to my morning routine of going out for a walk before breakfast because it’s wet, cold and dark.” 

What are the symptoms of SAD? 

If you have SAD, you might experience some of the signs and symptoms below. But it’s different for different people, and can vary season to season, so you might also have other kinds of feelings which aren’t listed here: 

  • lack of energy 
  • finding it hard to concentrate 
  • not wanting to see people 
  • sleep problems, such as sleeping more or less than usual, difficulty waking up, or difficulty falling or staying asleep 
  • feeling sad, low, tearful, guilty or hopeless 
  • changes in your appetite, for example feeling more hungry or wanting more snacks 
  • being more prone to physical health problems, such as colds, infections or other illnesses 
  • losing interest in sex or physical contact 
  • suicidal feelings 
  • other symptoms of depression

If you also have other mental health problems, you might find that things get worse at times when you’re affected by SAD. 

“I just can’t stay awake and the thought of having to go out, stay awake, make conversation. I just can’t do it.” 

When might I have SAD? 

SAD can affect you during any season or time of year. Some people experience it in summer, although less research has been conducted on this so you might find people are more aware of winter SAD. 

You don’t need to wait to see a pattern before seeking support – it’s ok to ask for help at any time. 

Our pages on treatment for SAD, treatment for depression and seeking help for a mental health problem have more information. 

“I close the curtains and wish it was dark so I could go to bed early but it’s broad daylight. I need to sleep and withdraw again from the world.” 

Experiences of facing stigma 

Lots of people have heard of SAD and depression in general, but this doesn’t mean that they understand what it’s like or how you’re affected. It doesn’t mean you ‘just feel a bit sad’, and there are many factors that can cause depression – for some people it develops without there being a specific reason. 

It can be frustrating and upsetting if people don’t understand this, but it’s important to remember that you are not alone. 

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