We all get the winter blues. As the days grow shorter and the frost glistens in the morning like a cold blanket, it’s natural to feel a little down. Everyone dreams of mornings when you don’t have to switch on every light in the house. However, some people can struggle with depression when the temperature and light drops, and this can be a serious problem. This form of depression is known as Seasonal Affective Disorder (SAD).
What Is Seasonal Affective Disorder?
Seasonal Affective Disorder (SAD), or ‘seasonal depression’, is a type of depression that you can experience during autumn and winter, when light is limited and the temperature drops. While it’s common for people to feel affected by the weather, or to have times of the year when you feel more uncomfortable than others, SAD is not a general bad mood. Although people can often have low moods or energy levels during the colder months, SAD affects your day-to-day living and can last a long time. If you find that your sleeping pattern is disrupted, and that your low mood is interfering with your everyday life, this could be a sign that you have depression. If you feel like this at the same time every year, you may have SAD.
What Are the Symptoms?
If you have SAD, you might experience some of the symptoms below. However, remember that SAD is different for different people, and can vary from season to season.
- Lack of energy
- Difficulty concentrating
- Not wanting to see people
- Sleep problems (sleeping less or more than usual/ difficulty falling asleep/ difficulty staying asleep/ difficulty getting up)
- Feeling sad, low, tearful, guilty, or hopeless
- Changes in your appetite (feeling hungrier/ eating more snacks/ comfort eating)
- Being more prone to colds, infections, or other illnesses
- Suicidal feelings
Also, if you have any pre-existing mental health problems or sleeping disorders, it’s possible that they’ll get worse when you’re affected by SAD.
What Causes Seasonal Affective Disorder?
While it’s known that seasonal changes can lead to seasonal depression, the exact causes of SAD aren’t clear. It’s generally thought that the things we know that can cause depression can also lead to SAD, and research has suggested that there a few things that could lead to SAD.1
1) The Effects of Light
When light hits the back of your eye, messages are sent to the part of your brain that controls sleep, appetite, temperature, mood, and activity.2 If there isn’t enough light, these functions can slow down and gradually stop. Some people seem to need more light than others in order to feel their best during the day, so these people are more likely to struggle with SAD. Find out about light therapy here.
2) Disrupted Body Clock
We all have an inner body clock, or a ‘circadian rhythm’, that tells us when we need to sleep or be awake. It’s influenced by daylight, which is why you’re up when the sun is up and you’re sleeping when the sun is down. One theory is that, if you experience SAD, your body clock isn’t working as it should. It could have slowed down due to the lack of daylight during colder months, and this leads to tiredness and depression.3 Find out more about your circadian rhythm here. Some researchers also think that a slower body clock is due to your sleep pattern, or ‘sleep phase’, starting at a different time. This is sometimes described as having a delayed sleep phase.4 You can find out more about this in our article, ‘What Is Delayed Sleep Phase Disorder?‘
3) High Melatonin Levels
When it’s dark, your brain produces a hormone called melatonin, which helps your body get ready for sleep. Melatonin is produced when it’s getting dark. Some people with SAD can produce much higher levels of melatonin during winter – this is also what happens to animals when they hibernate.5 The exact relationship between melatonin and SAD isn’t clear. However, researchers have found that, if you have high levels of melatonin, exposing yourself to bright light can help your melatonin levels drop to a more usual amount.6 Getting sufficient daylight to help SAD symptoms in winter is easier said than done, which is why people with SAD consider light therapy. You can read more about this in our article, ‘What Treatments Are There For SAD?’
4) Weather and Temperatures
Everyone has different experiences of particular seasons and types of weather. You might feel uncomfortable in hotter or colder temperatures. This could contribute to you developing depression, or any existing depression worsening, at these times of the year. Autumn and winter lead to lower temperatures and darker days, which can affect our sleep patterns. Read more about this in our articles, ‘Sleeping in Autumn’ and ‘Sleeping in Winter’.
If you have SAD, it’s important that you talk to your doctor as SAD is a form of depression, and you’ll need help to feel better. Your doctor can determine the best care for you, and can find out if there’s any underlying causes, like a pre-existing mental health problem. They can also refer you to a psychologist, or prescribe antidepressants. Don’t feel embarrassed or scared to approach your doctor – it’s important that you get the right care for you. You can find out more about treatments available in our article, ‘What Are the Treatments for Seasonal Affective Disorder?‘