What effect does light have on people's physiology?

Light through the human body affects the nervous system, nerve fiber optical signal transmission to other parts of the visual cortex and brain, control the body's biological clock and hormones, all have effect on the pituitary, pineal gland, adrenal gland, thyroid gland. Through the interaction between them, they can produce, reset and regulate the physiological and behavioral rhythms of the human body. Bright light causes an increase in body temperature and improves our cognitive efficiency. People generally in the morning when the temperature began to increase at 7, while the lowest temperature at 4 p.m.. A certain amount of sunlight, can increase the red blood cells and hemoglobin, increase saliva and gastric acid, promote appetite, improve immunity and resistance to disease, over the body.

Now there are a number of office buildings and schools, day and night to artificial lighting. Although these artificial lighting can meet the lighting needs, but because of the lack of certain radiation full spectrum natural light in the indoor light, long-term contact people natural light little chance related health problems will gradually appear, it is difficult to meet the physiological needs of the people.