Health impacts of the transition to winter time

The transition to winter time can affect sleep, digestion, and biological rhythms, even though the clocks are only set back by one hour. According to physician Beatrice Mahler, the body's circadian rhythm is guided by the central biological clock in the brain, which regulates signals for sleep, hunger, and alertness based on sunlight and daily routines.

Disruptions to this rhythm can persist for up to four days, potentially impacting mood, stress levels, and concentration. These changes may lead to a temporary increase in workplace errors and road accidents.

Metabolic processes are also affected; the speed of stomach emptying may decrease, particularly after the first meal of the day. This can result in higher blood glucose and triglyceride levels after meals, as well as reduced calorie burning. Additionally, the sudden shift in rhythm may lead to a slight increase in the incidence of cardiovascular events in the immediate days following the change. These metabolic disturbances are considered completely reversible as the central clock resynchronizes with ambient light, typically within one to three days.