Researchers found that sunlight exposure before 10 a.m. has a significant impact on a person's biological clock. Every additional half hour spent in the sun shifts the midpoint of sleep approximately 23 minutes earlier, and those who receive more morning light report better sleep quality.
Although evening sunlight also has an effect, it is generally less pronounced. The duration of sleep and the time required to fall asleep are not directly related to the amount of light received.
The authors of the study note that even without increasing sleep duration, morning sunlight helps to "tune" the body's internal clock. The habit of spending time outdoors in the morning can be a simple and accessible way to maintain healthy sleep in the modern pace of life.
