Symptoms of diabetes and diagnosis explained include glucose excess urine, excessive thirst, and weight loss. These symptoms are generally associated with diabetes and can be confirmed through a blood test. The blood test measures the amount of glucose in the blood, which is typically higher in diabetics. If the test results show elevated glucose levels, it can be used to diagnose diabetes. Other tests such as an A1C test, which measures the average blood sugar level over the past three months, and a urine test, which measures glucose levels in the urine, may also be used to confirm the diagnosis.