People who have metabolic syndrome typically have apple-shaped bodies, meaning they have larger waists and carry a lot of weight around their abdomens. It's thought that having a pear-shaped body — that is, carrying more of your weight around your hips and having a narrower waist — doesn't increase your risk of diabetes, heart disease and other complications of metabolic syndrome.
Abundant data suggest that patients meeting these diagnostic criteria have a greater risk of significant clinical consequences, the 2 most prominent of which are the development of diabetes mellitus  and of coronary heart disease. Pooled data from 37 studies involving more than 170,000 patients have shown that metabolic syndrome doubles the risk of coronary artery disease.  It also increases risk of stroke, fatty liver disease, and cancer.  (See Prognosis.)
^ Jump up to: a b Burt VL, Cutler JA, Higgins M, et al. (July 1995). "Trends in the prevalence, awareness, treatment, and control of hypertension in the adult US population. Data from the health examination surveys, 1960 to 1991". Hypertension. 26 (1): 60–69. doi:10.1161/01.HYP.26.1.60. PMID 7607734. Archived from the original on 2012-12-20. Retrieved 5 June 2009.
Hypertension is rarely accompanied by symptoms, and its identification is usually through screening, or when seeking healthcare for an unrelated problem. Some people with high blood pressure report headaches (particularly at the back of the head and in the morning), as well as lightheadedness, vertigo, tinnitus (buzzing or hissing in the ears), altered vision or fainting episodes. These symptoms, however, might be related to associated anxiety rather than the high blood pressure itself.
Most people who have metabolic syndrome have insulin resistance. The body makes insulin to move glucose (sugar) into cells for use as energy. Obesity, commonly found in people with metabolic syndrome, makes it more difficult for cells in the body to respond to insulin. If the body can’t make enough insulin to override the resistance, the blood sugar level increases, causing type 2 diabetes. Metabolic syndrome may be a start of the development of type 2 diabetes.
According to the Mayo Clinic, doctors may use other tests to diagnose diabetes. For example, they may conduct a fasting blood glucose test, which is a blood glucose test done after a night of fasting. While a fasting blood sugar level of less than 100 milligrams per deciliter (mg/dL) is normal, one that is between 100 to 125 mg/dL signals prediabetes, and a reading that reaches 126 mg/dL on two separate occasions means you have diabetes.