When I moved to Scotland, I realised I had a serious case of SAD

‘Tis the season, for at least 10 per cent of us, for annual Seasonal Affective Disorder (SAD). Triggered by lack of light, the condition is typified by a regular depression that drifts in around October, and only lifts in spring. This winter, with the continuing cost-of-living crisis and political turmoil may trigger more SAD than ever – and I should know.

Ever since I moved to the West Highlands of Scotland almost seven years ago, I have experienced SAD – or so I believe. Here, the shortest day – December 21 – runs from 8.45am to just 3.30pm. In deepest winter, the lack of light can be so spirit-lowering, it’s tempting to stay in bed all day, working from my boudoir like Barbara Cartland.

I’m normally an energetic person, filled with schemes – but not in winter, when a TV marathon under a furry blanket is all I can manage. Socialising takes a back seat, too; and I find myself craving vast bowls of white pasta. I can sleep for 10 hours if the alarm doesn’t go off, and waking up is like being pulled from a pitch black pothole.

Apparently, SAD can run in families, but I don’t know if anyone in mine suffers, as none of them has ever lived this far north. Last year, however, I’d had enough, and though I didn’t get a diagnosis (because getting a GP appointment seemed more trouble than flying to Barbados for the winter) I did take it upon myself to try and fix the problem – or at least alleviate some of the worst symptoms. 

“SAD is a type of depression that affects people mainly during winter,” says Dr Qian Xu, A&E doctor and medical director at REDjuvenate Medical. “Around one in 20 people has been diagnosed, but it’s more likely about 10 per cent of people suffer from SAD.”

The trigger is the effect of less light on circadian rhythms. “Your circadian rhythm is a 24-hour body cycle – your internal clock,” says Dr Xu. “During these cycles, your body carries out essential functions; the most important is the sleep-wake cycle. A decrease in light can disrupt this internal clock and lead to feelings of depression.”

Brain chemicals also come into play, she explains. “Serotonin is a chemical messenger that works with your nerve cells. It is sometimes known as the ‘happy chemical’, but it also affects sleep health, bone health, digestion and wound healing. And reduced sunlight can cause a drop in serotonin.”

Melatonin, a hormone produced by the brain’s response to darkness, is also affected by changing light levels. “This, in turn, can negatively affect sleep and mood.”

A survey of 5,000 Europeans from Coffee and Health found that when days shorten, 21 per cent of us become more anxious, 24 per cent find it harder to concentrate and 25 per cent lose motivation to exercise.

If you haven’t been diagnosed with SAD you may not be aware of the symptoms, including appetite changes – “We all love carbs but an increase in cravings can be a sign,” says Xu. Then there’s loss of interest in activities, disrupted sleep and low energy – a classic sign of SAD. “You may also notice concentration problems.” And, of course, my own worst difficulty: oversleeping, yet still feeling tired.

The further north you go, the lower the light levels at this time of year, and SAD is more prevalent among people who live far north or south of the equator. It may also be affected by a lack of vitamin D, which helps to produce serotonin.