Light effects on circadian rhythm

Circadian rhythms are like natural body clocks - they tell us when it’s time to eat, sleep, and even wake up. Light has a big effect on our circadian rhythms, because it helps send signals to our bodies about when it’s day and night. When it’s bright outside, our bodies know it’s daytime and we should be alert. But when it’s dark, our bodies know it’s time to go to sleep. The light we get during the day helps keep our circadian rhythms in check and on schedule.