When kids become obese, their blood pressure tends to climb along with their weight. As America's obesity epidemic worsens, an estimated 1.5 million children are now unknowingly hypertensive, according to a study in JAMA. Before they can be helped, their hypertension has to be diagnosed and it's never too soon. Hypertension puts kids at risk of long-term organ damage and other health problems in adulthood. Experts suggest that doctors assess a child's risk of hypertension starting as young as age 3 and consider sex, height and weight in determining the child's proper blood-pressure range.