This article was first published in the Jan/Feb 2024 issue of IQ, the exclusive magazine for Mensa members. Find out more about becoming a Mensa member here.

As the days grow shorter and temperatures begin to plummet in the autumn, many of us find our mood dipping too. We explore a seasonal condition that remains something of a mystery.

The winter blues, medically known as seasonal affective disorder (SAD), affects around two million people in the UK and is characterised by a propensity for depression, anxiety and lethargy. SAD wasn’t clinically diagnosable until the 1980s when physician Norman Rosenthal identified the disorder based on his own experience.

Moving from South Africa to the US, Rosenthal noticed that he felt down, tired and unproductive during the winter months, but the feeling faded when spring arrived. In 1984, Rosenthal published the first paper to scientifically name the condition SAD – a type of depression brought on by the dark days of winter.

Despite extensive scientific research, there is much about SAD that remains a mystery. It’s not clear why it’s significantly more common in the northern hemisphere, and we don’t understand why some people experience symptoms of SAD in the summer months.

We do have some clues about the disorder’s origins, however. Decreased exposure to daylight during winter, particularly in the morning, is thought to disrupt the body’s circadian rhythm cycles. This has a knock-on effect on our levels of key body-regulating hormones in the brain.

One leading theory about why we might feel particularly sluggish on winter mornings is that the lack of daylight disrupts our bodies’ release of melatonin, the hormone the brain releases every night to promote sleep. The early dawn light that seeps through our windows sets off a chain reaction that tells our internal body clock it’s time to wake up.

As daylight dwindles, melatonin may be released later and wear off later. This disruption to our internal clock is also thought to affect our levels of serotonin, which can cause changes to our mood, cognition and appetite. 

Tips for easing the winter blues

The usual advice for managing a low mood holds up when combatting symptoms of SAD: talk to loved ones, eat well, get enough sleep and avoid stress. While it’s important to seek medical advice for severe symptoms, there are also other things you can try:

• Step into the light: Since SAD is closely linked with decreased daylight, the NHS recommends those experiencing symptoms get as much exposure to sunlight as possible.
• Get moving: Physical activity triggers the release of dopamine and serotonin – hormones which regulate our mood. Regular exercise can help ease the symptoms of seasonal depression, particularly when taken outside and in the daylight.
• Build a bedtime routine: Create a consistent and calming night-time routine and try to wake up at the same time every day. Some SAD sufferers find sunrise alarm clocks helpful.

Reasons to be cheerful

Our daily diet of national and world news can be depressing, but good things are happening out there too. Check out this positive news site.