In the past, type 2 diabetes typically did not show up until well into adulthood, but now cases in American teens are rising rapidly. However, new research from Harvard, reported to the American Heart Association suggests teens who replaced just thirty minutes of daily sedentary time with moderate to vigorous physical activity could lower their insulin resistance by fifteen percent, thus reducing their risk of type 2 diabetes. Even replacing thirty minutes of sedentary behavior with sleep reduced insulin resistance slightly. Curiously, replacing sedentary behavior with low intensity exercise had little benefit. Another take away from the preliminary study at Harvard is that being active early in life can make a difference for long-term health.