Letting in the morning sun ensures sound sleep at night

There is one very important thing that people who wish for a sound sleep must observe. You must keep your lifestyle in line with the changes of day and night. Sleep is directly related to rotation of the earth and the consequent sunrise and sunset in a 24-hour cycle. All living creatures on earth have evolved to live in this 24-hour cycle, and our night's sleep is an important part of this rhythm. Adjusting your lifestyle to this cycle is the key to success in getting good quality sleep.

Exposing yourself to sufficient sunshine every morning is at the heart of this. Seeing morning sunshine stimulates supraoptic nucleotoxin in the brain through the optic nerve, and this sets the 24-hour cycle in motion. The body feels sleepy about 15 hours after the eyes see the morning light. This biorhythm is dependent on the existence of light, so seeing lots of sunshine during the day and no light at night is helpful. 

Guide Questions:
1. Based on the article, how can we get good sleep?
2. Discuss the importance of sleep and how is it connected to everything we do.
3. Illustrate how getting enough sun help us to become healthier.
4. Do you think you get enough sunlight? Why or why not?
5. What do you think are the other factors people don't like sunlight.

Vocabulary:
1. sufficient - enough; adequate
2. stimulate - raise levels of physiological or nervous activity in (the body or any biological system)