Sun Simiao, a doctor in the Tang Dynasty, said: "On the seventy-second day of spring, acid is preserved and sweetened to nourish the temper." It is also recorded in Gao Lian's "Eight Notes on Respect for Life" in the Ming Dynasty: "In spring, the taste of food should be reduced and the sweetness should be increased to nourish the temper." This means that when the liver fire is strong in spring, you should eat less acidic food, otherwise it will make the liver fire stronger and hurt the spleen and stomach. You can eat more sweets at this time. Throughout the spring, the principle of feeding and nourishing is to reduce acidity and improve sweetness and nourish temper. Because the liver is prosperous in spring, it is easy to cut spleen and stomach diseases, and the sour taste is the original taste of the liver, so at this time, it is necessary to reduce the sour taste, do not encourage the liver qi, and avoid being too prosperous, so as to protect the temper from being cut. Sweetness is the original flavor of spleen. In order to resist the possible invasion of liver qi, increasing sweetness and strengthening temper can strengthen the body's defense. Liu Xinming, a wise man in the East, has studied TCM health preservation for more than 30 years and has different views on TCM health preservation.