Don’t let winter make you SAD this year
Summertime, and the living was easy…
Summer is a distant memory, and unless you live in Queensland or the Northern Territory, it is a fair bet to say that your wardrobe has changed from t-shirts to warm sweaters to keep you snug. Winter, however, also has its charm: cozy ﬁres, hearty stews and long walks in a blustering wind can give us a feeling of wellbeing. Just make sure that winter does not make you SAD this year.
You may be one of 10% of people who suffer from S.A.D., Seasonal Affective Disorder, which is regarded as a form of (seasonal) depression. S.A.D. is also referred to as “winter depression” or “winter blues” and seems linked to a lack of sunshine. With S.A.D., symptoms start to develop in autumn and gradually worsen as winter progresses.
Winter’s subtle changes
Craving sweets and starchy foods and weight gain is not uncommon. Sleeping becomes more important; all you want to do is snuggle up under your doona. Science thinks this dates back to how our ancestors hibernated in winter, a season of hardship in ‘Caveman’ times. Conservation of energy was achieved during the long dark periods when foods was scarce; the added weight and increased sleeping time, reduced the need for hunting and gathering.
You may feel unmotivated, lethargic and more tired than usual; you may not understand why, and neither does your doctor. Seasonal Affective Disorder is often under- or misdiagnosed, perhaps even more so in Australia, the country perceived by many as “forever sunny.” In northern areas of Europe, the United States and Canada, S.A.D. affects an estimated 5-23% of the population.
Figures in Australia are unknown, but may well match these numbers, especially in the southern states. The amount of sunlight received during winter in Victoria and Tasmania can be as little as 3.8 hours per day. Not as bad as the United Kingdom where from December to February an average of 2.1 hours of sunlight is common. But still, just over 3 hours isn’t much. And if you’re stuck indoors at work during those few hours, you’ll get no direct sunlight at all, perhaps for days on end.
Old knowledge, backed up by modern-day research
Hippocrates, the forefather of modern medicine, mentioned lack of sunlight as a cause for lethargy in 400 BC. Before him, the ancient Egyptian Pharaohs practiced “sun worship,” as did native South American Incas. Without research, they recognized the importance of sunlight.
In modern medicine, S.A.D. was ﬁrst and formally recognized in 1984 by Norman Rosenthal, a professor at the American National Institute of Mental Health. His motivation for researching this phenomenon was his own ‘winter blues’. Light therapy helped and, inspired by this initial ﬁnd, further research was done in countries where grey skies are dominant for six months of the year.
Science now knows that lack of sunlight contributes to S.A.D. The pineal gland, located behind the forehead, reacts to sunlight. It is responsible for the production and release of hormones such as melatonin. This hormone is produced and released under the inﬂuence of light: made during the day, and released when darkness surrounds us – this hormone facilitates sleep.
Biochemical pathways convert melatonin to serotonin. Serotonin makes us feel good and levels are closely linked to mood changes. This is why Selective Serotonin Reuptake Inhibitors (SSRIs) are sometimes used for S.A.D. patients. These prescription medicines curb depression and S.A.D. by keeping serotonin levels balanced.
Sun, sun, oh glorious sun
Sunlight assists with the formation of vitamin D in the body. Low exposure to sunlight encourages low vitamin D levels. Scientiﬁc investigations point to a link between low levels of vitamin D and forms of depression. Modern-day lifestyles may not enable outdoor activities, especially in winter. Low vitamin D can also occur when dietary intake is inadequate.
Research shows our sleep rhythm changes when sunlight hours are reduced. This alteration may cause cravings for carbohydrates, especially after dark which can lead to weight gain. Carbohydrates are viewed as a source of “happiness,” possibly because they increase tryptophan levels. Tryptophan is one of the brain’s “happy hormone” molecules: It is required for serotonin production. Craving carbohydrates is viewed as a form of self-medication to improve a negative mood.
Don’t be SAD this winter
The medical world often treats S.A.D. with anti-depressants. Light therapy is also used, and is effective. Want to be pro-active to avoid these winter blues? Eat plenty oily ﬁsh or take cod liver oil; both will provide vitamin D. Whenever you can, go out and turn that little pineal gland towards the sun, let the light beam on your face. The more, the better. One bright light at the end of your SAD tunnel: Symptoms of SAD disappear in most people once spring starts. It is best to seek advice from a medical practitioner if symptoms persist.
This article first appeared in The Australia Times Health magazine.