Monosaccharides are sugars that can no longer be hydrolyzed, and common monosaccharides are glucose and fructose. Among them, glucose into the human body, do not need to be further hydrolyzed, can be directly absorbed into the blood, causing a rapid rise in blood glucose within a short period of time, the glycemic index is very high, glucose is also the basic unit of disaccharide and polysaccharide molecules. The most common polysaccharide is starch, and the main component of all kinds of food is starch. Starch is a high molecular weight polymer compound, after entering the body, under the action of amylase and maltase, it is gradually converted into glucose, and the glycemic index is significantly lower than that of monosaccharides. Fructose is also a monosaccharide, high in fruit, many sweet drinks also added a lot of fructose, fructose metabolism does not require the participation of insulin, the short-term impact on blood glucose is small, but the long-term intake of large amounts of fructose will cause insulin resistance, elevated blood uric acid, but also lead to obesity, which is also harmful to the body. Therefore, diabetic patients try not to eat food containing too much simple sugar.