Winter solstice and seasonal fatigue linked to light exposure

The upcoming winter solstice on December 21 marks a significant astronomical event where the Northern Hemisphere reaches its maximum tilt away from solar rays. Contrary to common belief, this phenomenon is not caused by the Earth being further from the Sun, but by the 23.5-degree axial tilt. This results in the shortest day of the year and the lowest solar altitude at noon.

This seasonal shift is linked to increased fatigue and biological changes. Scientific research suggests that the reduction in daylight hours affects the production of melatonin and cortisol, leading to seasonal exhaustion. To combat this, medical experts recommend morning exposure to natural sunlight for approximately 15 minutes to regulate the brain's suprachiasmatic nucleus, which helps suppress melatonin and boost serotonin levels without relying on caffeine or supplements.