When the damp and dreary winter months descend darkly upon you, do you find yourself a little down or depressed? Or perhaps you feel less productive, energetic and creative? Or maybe you are sleeping and eating more?
According to senior researcher Dr Norman E Rosenthal at the US-based National Institute of Mental Health (NIMH), and author of Winter Blues, answering yes to any of these telling signs may suggest you suffer from seasonal affective disorder (SAD). This biochemical imbalance, triggered largely by lack of sunlight, makes the jovial Dr Jekyll morph into the hideous Dr Hyde during weary winter months.
It is common to feel a little lazy or lacklustre in winter, but according to clinical psychologist Dr James Courtney from the Australian Psychological Society (APS), SAD is beyond feeling a little blue.
“SAD is a form of depression that interferes with a person’s ability to perform daily activities, as well as social and cognitive functioning,” he says.
While the condition is rarer in our nation compared to others further from the equator, research shows that approximately one in 300 Australians are affected by SAD. Relationships psychologist Michelle Thomson from Life Resolutions believes many sufferers reside in southern states where there is far less winter sun than summer rays.
“SAD is four times more common in women than men, and the average age of people when they first develop this illness is 23,” she says.
While this may be the case, Dr Courtney says men apparently report increased symptoms – ever heard of ‘man flu’?
Science and symptoms
Dr Rosenthal and his team at NIMH gave SAD its official title in 1984, following extensive research into the relationship between decreased hours of sunlight and the onset of depression during winter months.
The research reveals a lack of light decreases mood-regulating or ‘happy’ hormone serotonin, and stimulates sleep-inducing or ‘hibernation’ hormone melatonin, which can lead to depression when high concentrations are consistently present in the body.
“SAD symptoms usually start in autumn, get worse in winter, ease during spring and disappear by summer. Without treatment, there is a risk of the symptoms becoming more severe, and in extreme cases there is a risk of suicide,” Thomson says.
SAD symptoms include: depression and anxiety; lethargy; overeating, especially carbohydrates and sweets; poor sleep, insomnia or hypersomnia; decreased libido; poor concentration; social withdrawal; and body aches and pains. Symptoms usually reappear each winter, and an official diagnosis is generally made after two consecutive winters.
Get rhythm when you’ve got the blues
The circadian rhythm is not a rock band, but a vital tool in helping researchers decipher the exact cause of SAD, which has been a grey area for some time.
One particular study performed on a morning glory flower revealed an eye-opening relationship between sunlight and the sleep-wake cycle.
“The flower opened when the sun rose and closed when the sun went down,” says Jeff Collings, clinical director of sleep and snoring solutions company MCS Australia. “[The scientist] then put that flower into a dark room and observed it with candlelight. There were no cues of light and darkness, yet the flower still opened when the sun rose and closed when it went down.”
The scientist knew that the flower housed a gene that made it move in synchronicity with daylight, and according to Collings we all have this gene in our bodies that puts us in a 24-hour rhythm – this is our circadian rhythm or biological clock gene.
“A recent discovery is that light is absorbed through the melanopsin ganglion cells in the eye, which goes through the retina hypothalamic tract (RHT) and into the brain, stimulating the pineal gland,” Collings says. “The light runs through the hypothalamus through a set of neurons called the suprachiasmatic neurons (SCN); they are the clock that regulates your circadian rhythm.”
It all sounds very complicated, but it is really quite simple. The eyes are the windows to the brain; the more we draw back the curtains and welcome light in, the more we stimulate serotonin and supress the misery and melancholy of melatonin.
How to do this on a depressingly dark day? Simple: employ scientifically-proven blue light therapy, which was first trialled in the 1980s by Dr Rosenthal.
Become a bright spark
Ever noticed how light creates mood? A dimly lit restaurant, candlelight, firelight, starlight, sunrise or sunset create an ambience that subconsciously transcends to our sense of wellbeing.
In this type of therapy, light that mimics outdoor light is emitted from a ‘light box’. This is thought to cause a chemical change in the brain that lifts your mood and eases other symptoms of SAD, reports the Mayo Clinic in the US. Research has found over 80 per cent of sufferers generally recover within two weeks of commencing blue light therapy.
Intensity of the treatment depends on the power of the light source – expressed as ‘lux’ – and the distance from it. The light used in light therapy is up to 10,000 lux, which is about ten times brighter than a normally lit room.
“Fifteen minutes in front of this blue light represents being out in the sun for two hours,” Collings says.
He recommends busy office workers getting little to no natural light keep a blue light box on their desk.
“A ten minute burst when you are feeling a little low can really perk you up. The light works instantly and is completely natural.”
Potential side effects are minor and rare, and are generally alleviated by altering the light’s intensity and timing of treatment. Research suggests the pros greatly outweigh any cons.
Leading psychologist Anna Wirz-Justice recently predicted that 50 per cent of depressed patients will be treated by light rather than pills by 2015. Until then, anti-depressants and mood stabilisers remain a common – albeit controversial – form of treatment for many sufferers.
A combination of exercise and light is one of the most effective treatments for SAD, according to US research. A study by Duke University found depressed people who walked for 30 minutes three times a week felt less depressed. So next time you’re feeling a little blue, look to the light and get moving!