seasonal affective disorder

Everything you need to know about seasonal affective disorder

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  • As we head into colder months it's time to talk all things SAD

    Struggling with the reduced daylight hours? Sometimes it’s more than just a bit of the winter blues. The colder, darker weather can have a serious impact on your emotional well-being, a condition also known as ‘seasonal affective disorder’.

    You may have heard the term thrown around but not be totally sure what the condition entails. Below we break down what you need to know, from symptoms to treatments.

    What is seasonal affective disorder?

    Seasonal affective disorder is a particular type of depression that comes and goes with seasonal change. Symptoms usually appear in autumn and stay throughout winter, when daylight hours are at their shortest, and improves in spring and summer.

    Usually, the symptoms reoccur with the change of the season later in the year and can worsen when the clocks go back.

    seasonal affective disorder

    What causes seasonal affective disorder?

    The exact cause is unknown, but it is believed to be as a result of the reduced exposure to natural light over the winter months. According to the NHS, the primary theory is that a lack of sunlight can impact upon several of the body’s functions.

    For example, the production of melatonin, the body’s sleep hormone, may increase; The production of serotonin, which affects appetite, mood and sleep, may be lower, and; Your body clock may be disrupted as it relies on sunlight to time various functions.

    Around one in three people in the UK have SAD and women are 40% more likely to suffer with it, according to YouGov. Some people may also be more prone to the condition for genetic reasons, as it seems to run in families in some instances.

    seasonal affective disorder

    What are symptoms of seasonal affective disorder?

    According to the NHS, the most common symptoms of seasonal affective disorder can include feeling irritable, guilty, worthless, lethargic and or uninterested in normal every day activities. A person may also have a persistent low mood, sleep too much and find it difficult to get up in the mornings, and/or crave carbohydrates and gain weight.

    The symptoms of seasonal affective disorder, or SAD, mirror those of depression, but the person also experiences confusion because of the lack of obvious problems at home or at work,’ explains consultant psychologist Ingrid Collins of the London Medical Centre.

    ‘They may loose their appetite and their powers of concentration, their sleep may be disrupted, their anxious thoughts turn to doom and gloom for no logical reason, and even the simplest tasks become a struggle, with motivation at rock bottom. The immune system is less effective and therefore the person is more prone to illnesses.’

    seasonal affective disorder

    Seasonal affective disorder treatment options

    Ingrid says that recognising that you might be suffering from S.A.D. is the first major step towards recovery. The good news is that there is a wide range of options you can try out to see which has the most positive impact on your symptoms.

    See your doctor

    Your first port of call should always be your GP, who will advise you on the best course of action if you think you may be suffering from seasonal affective disorder. They may recommend a course of antidepressants or talking therapies if they think they would be beneficial to you.

    St John’s Wort

    St John’s Wort is a herbal supplement associated with alleviating low mood. If you are on any prescribed medication, you must speak to your GP before taking St John’s Wort, as it may interact with other medication including hormonal contraceptives, and can cause skin to become much more sensitive to sunlight.

    seasonal affective disorder

    Vitamin D

    ‘The lack of sunlight is the major cause of SAD, and as the action of sunlight on our skin causes us to manufacture vitamin D, a very important biochemical’, says Ingrid.

    Vitamin D has been linked to alleviating the symptoms of depression, including seasonal affective disorder. Reduced sunlight in winter means the body’s overall levels are lower, therefore it’s important to make more of an effort to incorporate more vitamin D-rich foods into your diet, or taking supplements.


    Lightboxes are one of the most popular treatment options for people who suffer with seasonal affective disorder. These lamps mimick natural daylight, and simply sitting in their glow for the recommended time per day (usually between 45-90 minutes) can really help to alleviate SAD symptoms.

    Lumie are the original creators of the Bodyclock wake-up light, an alarm clock which gently wakes you with daylight (rather than a harsh ringtone), giving your body a nudge to adjust its hormone levels accordingly. They have loads of different light box and clock options available so it’s worth exploring to find one that’s right for you.

    seasonal affective disorder


    ‘Exercise always helps because not only does it mean that your body as a result produces lots of extra endorphins – the happiness neuropeptide – but also you become far healthier and in consequence much more appreciative of your body as it becomes more and more like the body you want it to be’ says Ingrid.

    If you’re not the sporty type, don’t panic, as going for a walk is still a great way to encourage endorphin production and get some fresh air. Plus, a recent King’s College London study found that simply being outside can boost your mood for up to four hours afterwards, so it’s well worth forcing yourself to spend a few minutes outside surrounded by more green.

    Note that the purpose of this feature is to inform, not replace one-to-one medical consultations. For advice tailored specifically to you, always discuss your health with a doctor.

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