More and more people in the U.S. are becoming obese, physically inactive, or both. Obesity and physical inactivity aggravate insulin resistance. Also, people who are insulin resistant typically have an imbalance in their blood lipids (blood fat). They have an increased level of triglycerides (blood fat) and a decreased level of HDL (good) cholesterol. Imbalances in triglycerides and HDL cholesterol increase the risk for heart disease. These findings have heightened awareness of insulin resistance and its impact on health.