It's extremely difficult to change a lifetime of eating and exercise habits and stick with them, studies show.  Many people live in areas where it's tough to access healthy foods or exercise safely and affordably. The economics of eating in America make high-calorie foods an easy go-to. USA TODAY spoke with more than 50 nutrition and obesity experts, endocrinologists, pediatricians, social scientists, activists and people who have fought extra pounds. It's time to rethink obesity, they said. The experts pointed to an array of compounding forces. Social stigma. Economics. Stress. Ultra-processed food. The biological challenges of losing weight. In a six-part series, USA TODAY explores emerging science, evolving attitudes toward excess weight and how society itself can move toward a better perception of weight. Tap our link in bio to read the project, and swipe to learn more about what experts recommend for healthy weight.