For patients with high blood sugar, fruits like lychee and cinnamon must not be eaten. It must be clear that food for diabetic patients is divided into three levels, and this distinction is mainly based on the glycemic index of food, which is divided into low glycemic index, medium glycemic index and high glycemic index. High glycemic index refers to the glycemic index > 75 food, such foods have a great impact on blood sugar fluctuations, will quickly raise blood sugar in a short period of time, so patients with high blood sugar is not recommended to eat high glycemic index food. The cinnamon and lychee are the most typical fruits in the high glycemic index food, so for patients with high blood sugar, this kind of fruit must not be eaten, must keep in mind. And low glycemic index and medium glycemic index foods and fruits can be chosen to eat, because these foods have less impact on the fluctuation of blood sugar and are more conducive to the control of the disease.