The number of adults worldwide with Type 2 diabetes–formerly called adult-onset diabetes–has doubled over the past three decades, to 350 million people, according to a new study by the British medical journal The Lancet. Nearly 25 million Americans have the disease, and the study also shows that a healthy diet–over excercise–is the best method for treating it. Dr. Rob Andrews speaks with us. Andrews is a consultant and senior lecturer in diabetes and endocrinology at the University of Bristol, in England.