November 2022

Seasonal Affective Disorder: What is SAD and what can you do?

5 min read

As winter approaches and days get shorter, some people begin to experience Seasonal Affective Disorder (SAD), also referred to as winter blues or winter depression. SAD is a recurrent condition that arises in the fall and winter. For some, symptoms can be mild. For others, they can be terrible. Whether winter affects your mood, knowing about SAD is vital for recognising symptoms and reaching out for help. Find out more about the causes of SAD, alternative treatment choices to medication, and lifestyle practises to feel better in the winter months.

What is Seasonal Affective Disorder (SAD)?

SAD is characterised by seasonal patterns of recurrent depressive symptoms. Currently, the National Institute for Health and Care Excellence (NICE) suggests treating SAD similarly to depression. SAD is also referred to as "winter depression" since the symptoms are more pronounced and more severe during the winter months. The symptoms often begin in autumn with the worst months being December, January, and February. For some people, the symptoms of SAD begin to improve in the spring as days get longer..

It is normal to be affected by changing seasons and weather, or to feel more or less comfortable throughout certain periods of the year. You may find that seasons of the year or temperature drops and rises impact your daily routine, energy levels, sleeping schedule or eating habits. However, if your mental health is affecting your daily life, it could be an indication of depression. And if these changes occur around the same time each year, physicians may diagnose this as seasonal affective disorder (SAD) or seasonal depression.

Even though many have heard about SAD, this does not guarantee that they understand what it is or how it affects you. There are numerous reasons that might cause or exacerbate it, and it can have the same life-altering impact as other forms of depression. It is important to know you are not alone as an estimated 2 million people in the UK are affected by SAD every year.

What can cause Seasonal Affective Disorder?

At present, the causes of SAD are still unknown. It's believed to be a complex disorder which results not only from the interaction of vulnerability factors, but also the underlying genetic mechanisms. It could also be impacted by environmental and lifestyle factors.

Here are six potential causes derived from preliminary evidence:

  • Shorter sunlight hours - Sunlight enters your eyes and sends signals to the brain that help regulate energy levels, sleep, appetite, body temperature and mood. Insufficient sunlight can negatively impact any of these daily body functions.
  • Disrupted circadian clock - Sunlight helps your brain anchor your body clock, or circadian rhythm, to daylight hours. SAD symptoms may be caused by your circadian rhythm being out of sync with daylight, resulting in higher levels of fatigue and sleepiness.
  • Melatonin - Even though humans are not hibernating animals, we tend to feel sleepier in the winter. This is because our brain signals season changes to our body by changing the duration of high levels of melatonin – the hormone of sleepiness – during the year, which is longer in winter than in summer. Researchers observed higher daytime melatonin levels in people suffering from SAD.
  • Climate and location - SAD symptoms which may be caused by shorter daylight hours and a disrupted circadian clock may be worse or more frequent, depending on your geographical location. SAD is believed to be more prevalent in nations where the weather and daylight hours vary significantly between seasons, such as high-latitude countries in the Northern hemisphere.
  • Genetic vulnerability - Regardless of your geographical location, research shows that having close relatives with a history of SAD or depression may increase the likelihood of experiencing SAD symptoms in the winter months.

5 ways to ease Seasonal Affective Disorder symptoms

​​It is important to treat SAD because depressive symptoms can hinder the capacity to live life to the fullest, to take pleasure in daily activities and seasonal celebration with family and friends, and to perform effectively at a job. Common treatment options include professional mental health care such as therapy and counselling or medication. If you feel that you might have SAD symptoms, please refer to your GP. Here are five lifestyle recommendations that could assist in the management of SAD:

  1. View sunlight - Exposure to sunlight can be considered as one of the most efficient SAD treatments, boosting mood, improving sleep quality and feelings of calm and focus. Try opening a window as soon as the sun rises or going for a walk outside. You can make this a mindful practice by forest bathing in the park. Using a sun lamp that mimics natural outdoor light can be an effective alternative.
  1. Enjoy more sleep - Humans used to sleep one hour longer in the winter than in the summer, according to a study of preindustrial societies. We know sleep is sometimes the best medicine. Try adjusting your sleep schedule to each season to support your body in its daily functions.
  1. Getting regular exercise - exercise is a protective behaviour of depressive symptoms. In the UK, the National Institute for Health and Clinical Excellence, which works on behalf of the NHS, recommends treating mild clinical depression with exercise, among other various strategies. To achieve the best results, try practising aerobic exercise regularly at a comfortable level for you.
  1. Support your serotonin levels - Try eating healthy portions of tryptophan-rich foods such as salmon, poultry, eggs, seeds, nuts and soy can support the production of serotonin.
  1. Manage your stress levels - One of the best ways to prevent depression and support treatment for depression is managing long-term stress.

Well-being can be supported by adjusting our routine to each season. Our capacity to re-establish equilibrium and recover from changes and stresses in our environment can have an impact on our mental health, disposition, and energy levels not just during the cold season but throughout the year. At Harper, we understand the value of a practical and flexible well-being routine and we are here to support you — backed by science. Our Plans can provide you with the toolkit to build an actionable well-being routine while our Coaches are here to support, understand and be an accountability buddy for each step of your journey.

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