Sunlight plays a crucial role in regulating melatonin production, which is essential for sleepiness. When exposed to sunlight, melatonin levels drop significantly, signaling the body to become awake. In contrast, indoor lighting, particularly from electronic devices like tablets and smartphones, can also suppress melatonin but to a much lesser extent. This difference is vital for understanding sleep patterns, especially for night shift workers who face challenges when returning home in daylight.

For these workers, immediate exposure to sunlight can hinder their ability to sleep effectively, leading to the suggestion of using amber-lensed glasses. These glasses are designed to block blue light from the sun, providing relief by minimizing its impact on melatonin production. This insight highlights the importance of light in sleep regulation, particularly for individuals affected by irregular work hours.