Turning Back the Clocks: How It Impacts Your Health
On the last Sunday in October each year, the UK sets the clocks back by one hour at 2am, marking the start of shorter days and longer nights. This yearly event, while granting us an extra hour of sleep on that particular morning, has raised concerns regarding its effects on health and behaviour due to disruptions in sleeping patterns and adjustment to darker evenings.
Studies have suggested that altering the clocks twice a year can disturb the body’s natural sleep cycles, potentially impacting both physical and mental health. The human brain operates on a 24-hour biological clock, or circadian rhythm, which can be thrown off balance by changes in the sleep schedule. This disruption in the sleep cycle may not only lead to difficulties in readjusting but could also increase the risk of cardiovascular diseases.
A recent study by researchers at Harvard Medical School and the Massachusetts General Hospital found that sleep deficiency in mice led to the development of larger arterial plaques over time, compared to mice with regular sleep patterns. These sleep-deprived mice also exhibited higher levels of certain white blood cells in their system and decreased amounts of hypocretin, a hormone crucial for regulating sleep.
Moreover, losing an hour of sleep during the time change in spring has been associated with a surge in heart attacks and strokes. Hospitals in the US report a significant increase in heart attack visits on the Monday following the spring clock adjustment. Similarly, data from Zurich Insurance reveals a rise in car accidents during the period when clocks are turned back in November, particularly between 4pm and 7pm, as darker evenings impact drivers.
The mental health implications of turning back the clocks are also noteworthy. While the autumn change grants an extra hour of daylight in the morning initially, this advantage is short-lived as the days progressively shorten. The decrease in sunlight hours can contribute to low mood, depression, fatigue, and muscle pain, with some individuals experiencing seasonal affective disorder (SAD) due to the lack of daylight.
Symptoms of SAD include persistent low mood, loss of interest in regular activities, irritability, feelings of despair or guilt, and excessive sleeping. The NHS highlights that reduced sunlight exposure may disrupt the production of melatonin and serotonin, affecting mood and sleep regulation. It is essential to be mindful of these potential health impacts associated with the biannual clock changes.