Seasonal Affective Disorder (SAD) is recognised as a genuine condition and there’s compelling research to suggest that SAD exists. Studies suggest around a third of people suffer from SAD, which was first identified by US scientists in the early 1980s.
Symptoms go from lower energy levels to severe depression. Most people find themselves somewhere in the middle – not paralysed with despair, but as the days shorten, they struggle to get out of bed, and have to force themselves to go outside and absorb any available light. Sufferers can feel profoundly miserable, without anything specific reason. Gloom is often alleviated by a walk in the sunshine, or a sun-filled holiday abroad. Most people resign themselves to SAD symptoms being part of winter life.
Symptoms listed by the UK National Health Service include: persistent low mood; loss of interest in normal activities; irritability; despair, lethargy, struggling to get up and craving carbohydrates.
However, a new study of more than 5,200 people conducted by the Netherlands University in Groningen discovered that lack of sunlight does not influence mood – on the contrary, people who are of a natural sunny disposition are unaffected by the nights drawing in.
Some people may feel worse in winter simply because they associate their negative mood to factors outside their control… but winter could simply be stressful because of an increase in other depression-related symptoms. In other words, people think they’ve got SAD because they just expect to have symptoms. The Groningen study’s key finding was that overall, only those already high in neuroticism – those more likely to suffer negative emotions such as anxiety, fear and worry – felt worse at the end of the summer.
People who are already vulnerable to emotional instability are more likely to be impacted by the change in the seasons. Lack of light and the change in seasons increase vulnerability factors that can make people more prone to experiencing depression and low mood – those who suffer from anxiety especially so. In other words, it’s all in the mind, so no surprise that being anxious increases the likelihood of SAD.
However, none of the above makes SAD less real – it simply means that people suffering from anxiety or depression are likely to feel worse. A reduction in sunlight availability can affect the hypothalamus in the brain and cause us to produce too much melatonin, which makes us more sleepy and lethargic. Lack of sunlight can inhibit production of the brain chemical serotonin, without which, we may experience bouts of low mood and depression.
SAD is a genuine condition closely linked to depression, so sleeping patterns can also affect the severity of SAD. In winter, we don’t get enough light to set the biological clock that synchronises our rhythms over 24 hours, so they drift later and later. If you have a ‘late’ clock when it comes to sleeping and waking, you may be more likely to be more vulnerable to depression.
Getting up early provides the key to feeling better. Recent research discovered a photo receptor in the eye sensitive to light. As light hits a certain cell in the retina, it transmits information that it’s dawn or dusk, light or dark, direct to your brain’s biological clock.
By absorbing light first thing in the morning, you regulate the rhythms in your body. But without that trigger, the brain fails to receive the right signals, and you’ll struggle to wake up. Worse, you’ll crave carbs and feel gloomy.
However the condition is not necessarily connected to direct sunlight, but to the length of the day, whether sunny or not, which is presumably why some studies have found no appreciable effect of Vitamin D on SAD. One solution is to get up as soon as it gets light.
And then there’s good sleep hygiene – make sure there are not too many distractions in your bedroom, no stimulants before bed and keep the room cool. Some people find a light-box useful. It produces a bright, white light that mimics sunlight to encourage the brain to produce serotonin and reduce sleep-inducing melatonin. One study found A light-box also decreased cravings for carbs.
And then there’s exercise. When you exercise, your brain releases feel-good hormones, endorphins and serotonin, which give you a natural boost and trigger positive feelings. In addition, your body also becomes better at managing the stress hormone cortisol.
Copyright Andrew Newton 2020. All rights reserved.