Random blood sugar test. A blood sample will be taken at a random time. Regardless of when you last ate, a blood sugar level of 200 milligrams per deciliter (mg/dL) — 11.1 millimoles per liter (mmol/L) — or higher suggests diabetes.
Symptoms of type 1 diabetes often appear suddenly and are often the reason for checking blood sugar levels.
Anyone with a body mass index higher than 25 regardless of age, who has additional risk factors, such as high blood pressure, abnormal cholesterol levels, a sedentary lifestyle, a history of polycystic ovary syndrome or heart disease, and who has a close relative with diabetes.
Anyone older than age 45 is advised to receive an initial blood sugar screening, and then, if the results are normal, to be screened every three years thereafter.
Women who have had gestational diabetes are advised to be screened for diabetes every three years. Anyone who has been diagnosed with prediabetes is advised to be tested every year.