High insulin does not necessarily mean diabetes. Insulin is a blood sugar-lowering hormone secreted by the beta cells of the pancreas, and insulin is the only blood sugar-lowering hormone in the body. Diabetic patients can have high insulin levels, and non-diabetic patients can also have high insulin levels when they develop insulin resistance. Because when a patient develops insulin resistance due to obesity and other reasons, the body must promote insulin secretion in order to maintain normal blood glucose, so there may be a situation where insulin is high and blood glucose is normal. When even increased insulin cannot maintain blood glucose in the normal range, diabetes will occur. Therefore, insulin is an indicator that responds to the function of pancreatic beta cells and is not the basis for the diagnosis of diabetes. The diagnosis of diabetes needs to rely on fasting blood glucose, two-hour oral glucose tolerance test or two-hour postprandial blood glucose, and glycated hemoglobin, not insulin levels.