Bigu, also known as "Quegu", "Broken Valley", "No Valley", "No Valley" and "No Valley", does not eat grains, eats gas and absorbs natural energy. In the past, Taoism was considered as a method of cultivating immortals, but now it is a health care teacher who uses energy to cultivate body and mind. People eat whole grains, and feces accumulate in the intestines to produce foul smell; At the same time, Taoism believes that it is necessary to remove the dirty gas in the intestine and remove the three corpse worms. Therefore, Taoism imitates the immortal behavior described in "Zhuangzi Xiaoyao Tour", hoping to achieve the goal of becoming immortal. Modern people are rich in food, and it is good to eat too much. The purpose of crossing the valley is to preserve health, detoxify, beautify, maintain beauty and recuperate.