Yam contains amylase, polyphenol oxidase and other substances, which is conducive to the digestion and absorption of the spleen and stomach. It is a food and medicine product that flattens the spleen and stomach. Regardless of spleen yang deficiency or stomach yin deficiency, it can be eaten. Clinically, it is commonly used to treat diseases such as weakness of the spleen and stomach, lack of food, fatigue, diarrhea;