Cholesterol check. The buildup of plaque in the vessels carrying blood to the tissues begins in the late teens and early adulthood. In fact, getting your cholesterol level measured at age 22 predicts the risk of a heart attack for the next 30-40 years, according to the National Heart, Lung, and Blood Institute. And if your cholesterol is found to be borderline high (200-239 mg/deciliter) or high (240 mg/deciliter or above), you have time to make lifestyle changes, such as eating healthfully and exercising regularly, so you'll have a better chance of preventing heart disease later in life.
Diabetes check. If you're under 45 years old and have at least one risk factor for diabetes, such as being overweight or obese or having a parent or sibling with the condition, ask your doctor for a blood-glucose test. If you're diagnosed with pre-diabetes (a new classification defined by blood-glucose levels above normal but not high enough to be diagnosed as diabetes) or type 2 diabetes, you can improve your health and control blood glucose with a healthy diet and regular exercise (both cardio and weight training), which improve your insulin sensitivity; in some cases, though, medication is required.