There are many kinds of disaccharidases in the mucosa of small intestine in normal human, such as lactase which can break down lactose into galactose and glucose; maltase which can break down maltose into glucose and isomaltose; isomaltase which can break down isomaltose into two molecules of glucose; sucrase which can break down sucrose into glucose and fructose; and alglucosidase which can break down algose into two molecules of glucose. For some reason, disaccharidase is lacking, and thus the digestion and absorption of disaccharides is impaired, resulting in diarrhea. This clinical condition is not uncommon, but is often not taken seriously. Hawthorn berries can be eaten raw or as jam and fruit cake, and dried and used as medicine, which has the effect of strengthening the stomach, eliminating stagnation and relieving qi and dispersing blood stasis. Yam contains amylase, polyphenol oxidase and other substances, which are beneficial to the digestion and absorption of the spleen and stomach, and is a dual-use medicine and food product. Japonica rice contains more protein, fat and vitamins, which can lower cholesterol, reduce the chance of heart attack and stroke, and has a variety of nutrients such as fat, calcium, phosphorus, iron and B vitamins.