What is seasonal affective disorder?

Winter is well and truly here. While we all enjoy a bit of a whine about the cold, for some people the winter blues can become more than regular seasonal gloom. Seasonal affective disorder (SAD) is real and can hit you hard. If you suspect you struggle with SAD each year we’re here to help. We’ll explain what SAD is, what causes seasonal affective disorder, how SAD can make you feel and how to deal with seasonal affective disorder.

What is SAD?

Seasonal affective disorder (SAD) is a mood disorder. It causes people to feel depressive symptoms at a specific time of the year, most often during the winter (although SAD does affect some people during other seasons). People with SAD often have no mental health issues throughout the rest of the year.

In the past, bouts of winter sadness were usually written off as just a case of the winter blues, but today SAD is a clinically recognised mood disorder, like depression or anxiety. Some mental health practitioners see it as its own mood disorder, while others classify it as a seasonal form of depression.

Whatever the classification, SAD is real and shouldn’t be casually dismissed or downplayed. SAD can cause mood problems, affect your relationships and impact your social and work life. It can even harm your health. 

What causes SAD?

SAD is complicated and has multiple causes that vary by person. The main cause of SAD is thought to be a decline in sunlight during winter months, as less sunlight can disrupt your serotonin and melatonin levels.

Serotonin is a natural chemical called a neurotransmitter that’s produced by your nerve cells. It has lots of functions which include helping to regulate your mood, thinking, memory and reward systems. Sunlight stimulates serotonin production. Your serotonin levels can fall during the winter months and this drop is associated with depression.

Melatonin is a hormone produced by your pineal gland that helps you fall asleep. Your body makes melatonin as light levels fall in the evening. During winter months there is a lack of strong sunlight to wake you up and kick-start your circadian rhythms. This means that your pineal gland can make melatonin later in the day which can make it harder for you to fall or stay asleep. Not getting enough sleep can also cause depressive symptoms and lower your energy levels and motivation.

Around 10-20% of people get SAD to some degree. It’s thought that these people are more susceptible to changing levels of sunlight.

What are the symptoms of SAD?

Again, the symptoms of SAD can vary by person, but the most common seasonal affective disorder symptoms include:

  • Feelings of depression such as sadness, emptiness and hopelessness
  • Feelings of guilt and low self-worth
  • An increase in other negative thoughts including suicidal thoughts
  • Low energy levels
  • A fall in motivation
  • A loss of interest in the things you usually enjoy
  • Less care spent on your personal hygiene and taking care of your health
  • Problems with sleep
  • An increase in appetite, particularly for high-carb and sugary foods
  • Weight gain

We all have bad days. It’s perfectly normal to feel some of these symptoms, particularly on grim winter days when you’re stuck inside or commuting in the dark. However, if these feelings persist and affect your daily life, you may well have SAD.

Can you be diagnosed with SAD?

SAD is a clinically recognised mood disorder in the UK. So yes, you can be diagnosed with seasonal affective disorder. If you think you have SAD the first step is to see your GP. They can either diagnose you themselves or refer you to a mental health specialist who can.

Who is at risk of SAD?

Anyone can get SAD, but you’re more likely to develop it the further north or south you live from the equator (this includes the north of England and Scotland) as these locations get less sun in the winter. Women, young people and people with vitamin D deficiencies also have a higher risk of SAD.

How long does SAD last?

SAD can have different durations for different people. However, it can last as long as sunlight levels are low, even from autumn into spring. The further north or south you live from the equator, the longer the winters last and the longer your SAD can affect you.

Is Vitamin D good for SAD syndrome?

People who have low levels of vitamin D are more likely to have SAD and depression in general. Taking a vitamin D supplement can help to treat SAD. However, it may not be sufficient on its own and you’ll likely need a range of treatments to keep SAD at bay.

How to treat SAD?

If you suffer from SAD, you’ve got a range of options to help you treat it. You may find you respond better to some treatments than others. It’s worth experimenting to find out which ones are most effective for you. Seasonal affective disorder treatments include:

Trying to get as much sunlight as possible: A simple treatment is to make a conscious effort to maximise the amount of time you spend in the sun. If you work indoors or have other commitments this might not be too easy, but try and take regular breaks outdoors when the sun is shining.

Light therapy: You can buy light boxes, light lamps and other light products that emit light at the same wavelengths as sunlight. They essentially work as sources of natural light at home – doses of this light can help some people overcome SAD.

Antidepressants: Antidepressant medications have proven to be effective treatments for SAD, particularly selective serotonin reuptake inhibitor (SSRI) medicines that increase your serotonin levels.

Vitamin D: Sunlight stimulates your body to produce vitamin D and low levels of vitamin D is associated with depression. Taking a vitamin D supplement can help to counter SAD.

Counselling: Talking therapy such as cognitive behavioural therapy (CBT) or psychodynamic therapy can be an effective treatment for SAD, particularly when used alongside other treatments such as light therapy or antidepressants.

Make positive lifestyle changes: A whole range of behaviours are associated with reducing depression, including all the usual ones you’d expect. Eating the best diet you can, getting regular exercise, losing excess fat, getting enough sleep each night and cutting back on alcohol and recreational drugs can all help to keep depression at bay.

If you have SAD don’t ignore it. The disorder can take a real toll on you during the winter months. Try the tips we recommended above. We also recommend you make an appointment to see your doctor to discuss SAD with them.