Low testosterone (T) levels increase the risk of heart disease, type 2 diabetes, muscle and bone loss, prostate cancer, and depression.  It also impairs metabolic health, promotes obesity, and decreases sexual performance.  It is a serious public health issue that robs men of energy levels and quality of life.  A study from the New England Research Institute and Massachusetts General Hospital in Boston on men 30-79 years of age found that low testosterone levels increased the risk of Metabolic Syndrome in a wide variety of racial and ethnic groups.  The Metabolic Syndrome is a group of symptoms that include high blood pressure, abnormal blood fats, inflammation, poor blood sugar regulation, abdominal fat deposition and blood clotting abnormalities.  Low blood testosterone is an important marker of poor metabolic health and should be a standard measurement in aging men.  (Journal Clinical Endocrinology Metabolism, 93:3403-3410, 2008)