How Suicide Rates Are Impacted by SAD (Seasonal Affective Disorder)

As the days grow shorter and sunlight becomes scarce, many people find their mood taking a downturn. 

While it’s normal to feel a little low during the darker months, some individuals experience a more severe condition known as Seasonal Affective Disorder (SAD), sometimes called the winter blues. 

For those living with depression or other mental health conditions, SAD can be a dangerous trigger, and research suggests it may contribute to fluctuations in suicide rates during the colder months.

Understanding SAD

SAD is a type of depression that typically occurs during autumn and winter, when natural daylight hours are reduced. Symptoms can include:

Persistent low mood and lack of energy

Sleep problems (either too much or too little)

Loss of interest in everyday activities

Feelings of hopelessness or guilt

Changes in appetite and weight

The exact cause isn’t fully understood, but it’s believed to be linked to reduced sunlight exposure, which affects serotonin (a mood-regulating neurotransmitter) and melatonin (a hormone that controls sleep patterns). Low levels of both can contribute to feelings of depression, lethargy, and disrupted sleep.

SAD and Suicide Risk

While SAD itself doesn’t cause suicide, it can intensify underlying mental health problems. Studies in the UK and other northern countries show that suicide rates often fluctuate seasonally, with some evidence suggesting increased risk during the late winter and early spring months.

This may seem surprising — why spring? Mental health experts suggest that people who have struggled through the dark winter months may suddenly have more energy as daylight increases, which can tragically increase the risk of acting on suicidal thoughts before full recovery takes hold.

Who Is Most at Risk?

Anyone can develop SAD, but certain groups are more vulnerable:

Those with a history of depression or bipolar disorder

People living far north where winter daylight is limited

Individuals who spend little time outdoors

Those with vitamin D deficiency

People experiencing loneliness or social isolation

The COVID-19 pandemic and the ongoing cost of living crisis have both contributed to increased isolation and financial anxiety, heightening vulnerability for many.

Recognising the Signs

If you or someone you know is withdrawing socially, losing interest in favourite activities, expressing hopelessness, or speaking about death or suicide — these may be warning signs that should never be ignored. Early intervention saves lives.

Ways to Cope and Find Help

There are several effective treatments and strategies for managing SAD:

Light therapy – using a special SAD lamp to mimic natural daylight

Vitamin D supplements – particularly during the winter months

Exercise – even gentle outdoor activity can improve mood and serotonin levels

Talking therapies – such as CBT or counselling

Medication – antidepressants may be prescribed if symptoms are severe

Small lifestyle changes can make a big difference, too — spending time outdoors during daylight hours, opening blinds early, and maintaining social contact can all help.

Getting Support

If you’re struggling, you are not alone — and help is always available. In the UK, you can contact:

Samaritans – 116 123 (24/7, free)

Mind – 0300 123 3393

Shout – text 85258 for 24/7 crisis support

CALM (Campaign Against Living Miserably) – 0800 58 58 58 (for men)

NHS 111 – for urgent mental health help

Reaching out is the bravest step you can take. Whether it’s winter or summer, your life has immense value — and there are people ready to listen and help you through.