diabetes—is a condition in which the body does not produce enough, or properly respond to, insulin, a hormone produced in the pancreas. Insulin enables cells to absorb glucose in order to turn it into energy. In diabetes, the body can't use its own insulin as well as it should, doesn't make enough insulin, and sometimes both. This causes glucose to accumulate in the blood, often leading to various complications. The American Diabetes Association reported in 2009 that there are 23.6 million children and adults in the United States—7.8% of the population, who have diabetes. While an estimated 17.9 million in the US alone have been diagnosed with diabetes, nearly one in four (5.7 million) diabetics are unaware that they have the disease.