Seasonal Affective Disorder (SAD) is a form of seasonal depression that typically appears during the autumn and winter months, when daylight hours are shorter. For this reason, it’s often called winter depression.
Around 1 in 15 people in the UK experience symptoms of SAD between September and April, so someone you know may be affected. The good news is that recognising the signs and knowing how to support them can make everyday life feel brighter throughout the year — even on the cloudiest days.
Seasonal Affective Disorder is a type of depression that follows a predictable seasonal pattern. Symptoms usually worsen in the darker months and improve when spring and summer bring more natural daylight.
SAD is linked to reduced sunlight exposure, which disrupts several natural processes in the body:
Melatonin is the sleep hormone. In winter, some people produce too much of it, leading to increased tiredness and low energy.
This brain chemical affects mood, appetite and sleep, with links to feelings of depression. A drop in serotonin can therefore throw these out of kilter.
We rely on daylight to regulate our body clock. Shorter days can throw this rhythm off balance, contributing to SAD symptoms.
It’s normal to feel a little sluggish during winter, but if someone you know is acting out of character, they may be experiencing SAD. For around 3% of people, symptoms can significantly impact daily life.
Look out for:
Key difference:
People with SAD often sleep more and eat more, while those with non-seasonal depression may do the opposite.
It’s important to remember that the severity of SAD varies from person to person.
There are many small, meaningful steps you can take to help someone you know who is experiencing SAD.
Prepare or recommend meals rich in vitamins, lean proteins and complex carbohydrates that support serotonin, such as oatmeal, omelettes, lean chicken, nuts and popcorn.
Limit caffeine where possible — it can heighten anxiety and disrupt sleep.
Drinking enough water helps prevent fatigue and headaches, which can worsen low mood.
Daylight helps reset the body clock and boosts mood. Try suggesting:
If you're nearby, join them — even a 20-minute walk helps.
Movement increases endorphins and improves energy levels. This might include:
Any activity that raises the heart rate can make a difference.
Having enjoyable activities ahead can boost positivity. You might suggest:
Choose options that feel manageable and uplifting.
Ask how they’re feeling in a gentle, non-judgmental way. If they seem irritable, stay patient. Over time, you might spot patterns that help you both manage tough moments more effectively.
A structured bedtime routine is essential when sunlight is limited.
Help them by suggesting:
Help them maximise exposure to natural light:
Light therapy boxes (10,000 lux) can reduce symptoms for up to 80% of people, often within 3–4 days.
Talking therapies, such as counselling or Cognitive Behavioural Therapy (CBT), can help someone understand their thoughts, manage difficult emotions and build healthier coping strategies. Encourage them to book an appointment with a Doctor Care Anywhere GP or Mental Health Practitioner, who can offer personalised support and guidance. If appropriate, they can also signpost the person to HelloSelf, where they can be matched with a leading therapist and use therapist-designed tools to help them remember, practise and apply what they learn between sessions.
If their symptoms become severe, persistent or begin to interfere with everyday life, encourage them to speak to a Doctor Care Anywhere GP or Mental Health Practitioner. They can assess symptoms, provide tailored advice and arrange further support if needed. In some cases, medication or structured therapy may be recommended — particularly if SAD returns each year. Starting treatment before winter can often be the most effective approach.
It’s completely natural to worry about someone you know if they’re not acting like themselves. Your support, understanding and patience can make a meaningful difference. With the right steps and early action, it’s possible to reduce the impact of SAD and help them feel brighter during the darker months.
Seasonal Affective Disorder is a type of depression that follows a seasonal pattern, usually worsening during winter when daylight hours decrease.
Common signs include low mood, tiredness, increased sleep, cravings for carbohydrates, irritability, lack of motivation and reduced interest in activities.
SAD is usually caused by reduced sunlight in autumn and winter, which can disrupt the body clock, lower serotonin levels and increase melatonin production.
You can help by encouraging daylight exposure, healthy routines, exercise, balanced meals, rest, talking therapies and by offering understanding and patience.
Yes. Light therapy using a 10,000-lux lamp is effective for many people and can improve symptoms within a few days of consistent use.
They should seek medical advice if their symptoms are severe, persistent, or return each winter. A GP can discuss treatment options such as therapy or medication.
Are you struggling with anxiety and looking for effective ways to manage it? Join Dr. Emma Eade from Doctor Care Anywhere as she explores common anxiety symptoms and practical strategies to regain control of your mental wellbeing.