Guava leaves do not work to lower blood sugar. Some studies have shown that certain active ingredients extracted from guava leaves can lower blood glucose concentration in diabetic mice, but there are no clear studies proving that they can lower blood glucose concentration in humans, so guava leaves do not work to lower blood glucose. Foods and certain proprietary herbs are sometimes an aid to blood sugar management, but they cannot replace hypoglycemic medications for the purpose of blood sugar control. Ways to lower blood glucose include appropriate physical exercise such as running, jumping rope, swimming, etc., good dietary management and control, and treatment with insulin injections or oral hypoglycemic drugs such as acarbose as prescribed by the doctor. Patients diagnosed with diabetes should be standardized to cooperate with the doctor’s treatment, food alone can not serve the purpose of lowering blood sugar, please follow a scientific treatment plan.