Sunlight, mountains, rivers, atmosphere, animals and plants are the natural environments on which human beings live, and all of them have direct or indirect effects on human physical and mental health. There are biological factors and physical and chemical carcinogens such as viruses and bacteria that are harmful to human health in nature. Especially in the last century, man-made industrial and agricultural pollution has spread to water sources, atmosphere and green vegetation, affecting food, clothing, housing and transportation, posing a great threat to human health and life.
It can be confirmed from the five longevity areas that have been discovered in the world. The living environment conducive to human health and longevity is some inaccessible mountainous areas and coastal areas without industrial pollution. The reason is that there are fewer factors that are harmful to health, and there are a lot of negative ions that are beneficial to human survival.