At the age of sixty-six, Bryanna Heartley had what most would consider an ideal life. She was the matriarch of a growing family, each of her children successful in his or her own way. She had a happy marriage. She had close friends, financial security, overseas holidays, and a psychology career that she truly loved. However, there was a problem: Bryanna was obese. She suffered from bouts of asthma, problems with reflux, high cholesterol,...