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.
What Is Seasonal Affective Disorder?
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.
What causes SAD?
SAD is linked to reduced sunlight exposure, which disrupts several natural processes in the body:
- Overproduction of melatonin
Melatonin is the sleep hormone. In winter, some people produce too much of it, leading to increased tiredness and low energy.
- Lower serotonin levels
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.
- Changes in internal body clock
We rely on daylight to regulate our body clock. Shorter days can throw this rhythm off balance, contributing to SAD symptoms.
Signs and Symptoms of SAD
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:
- Persistent low mood - They may appear irritable, anxious or withdrawn. Conversations feel strained, and they might seem quieter or snappier than usual.
- Avoiding social situations -Someone who normally enjoys going out may decline invitations or prefer staying indoors.
- Heightened emotions -They may cry more easily, show frustration or use negative language expressing feelings such as hopelessness or guilt.
- Loss of interest - Hobbies and activities they once enjoyed may no longer appeal. Their libido may also decline.
- Low energy and fatigue - They may struggle to get up in the morning and feel sleepy or drained throughout the day.
- Increased appetite and cravings - Comfort foods, especially carbohydrates and sweets, may become more tempting. This can lead to winter weight gain.
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.
How to Support Someone You Know With Seasonal Affective Disorder
There are many small, meaningful steps you can take to help someone you know who is experiencing SAD.
- Encourage balanced, mood-boosting meals
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.
- Remind them to stay hydrated
Drinking enough water helps prevent fatigue and headaches, which can worsen low mood.
- Help them get more daylight
Daylight helps reset the body clock and boosts mood. Try suggesting:
- A lunchtime walk
- Outdoor weekend plans
- Sitting near windows during the day
If you're nearby, join them — even a 20-minute walk helps.
- Suggest regular, gentle exercise
Movement increases endorphins and improves energy levels. This might include:
- Walking or cycling to work
- Home workouts
- A weekend hike
- Even housework
Any activity that raises the heart rate can make a difference.
- Plan things for them to look forward to
Having enjoyable activities ahead can boost positivity. You might suggest:
- A concert or comedy night
- A day trip
- A short break somewhere sunnier
- A cosy meal out
Choose options that feel manageable and uplifting.
- Talk openly and look for triggers
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.
- Encourage a healthy sleep routine
A structured bedtime routine is essential when sunlight is limited.
Help them by suggesting:
- A calm, dark and tidy sleep environment
- Reduced screen time before bed
- Avoiding caffeine later in the day
- A relaxing wind-down routine such as reading or a warm bath
- Make their environment brighter
Help them maximise exposure to natural light:
- Keep curtains and blinds open
- Encourage sitting near windows
- Keep rooms bright and uncluttered
Light therapy boxes (10,000 lux) can reduce symptoms for up to 80% of people, often within 3–4 days.
- Explore talking therapies and professional support
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.
- Encourage them to speak to a GP or Mental Health Practitioner if symptoms worsen
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.
FAQs
- What is Seasonal Affective Disorder (SAD)?
Seasonal Affective Disorder is a type of depression that follows a seasonal pattern, usually worsening during winter when daylight hours decrease.
- How do I know if someone I know has SAD?
Common signs include low mood, tiredness, increased sleep, cravings for carbohydrates, irritability, lack of motivation and reduced interest in activities.
- What causes someone to develop Seasonal Affective Disorder?
SAD is usually caused by reduced sunlight in autumn and winter, which can disrupt the body clock, lower serotonin levels and increase melatonin production.
- How can I support someone I know who has SAD?
You can help by encouraging daylight exposure, healthy routines, exercise, balanced meals, rest, talking therapies and by offering understanding and patience.
- Is light therapy useful for people with SAD?
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.
- When should someone with SAD speak to a GP?
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.
