After stepping on her bathroom scale in the summer of 2010, Diana Worden Karmin finally decided that - at 52 years old and weighing 263 pounds - it was time to escape from the crushing chest pains, the nearly crippling joint pain, and the deepening depression with a goal of getting under 200 pounds. By January 2011, after months of dieting and exercise, she slipped into a pair of Size 16 jeans and felt absolutely triumphant. Eighteen months later,...