For four weeks, 20 healthy volunteers checked into a research center hospital and were served a variety of tempting meals: cinnamon french toast, stir-fry beef with broccoli and onions, turkey quesadillas and shrimp scampi. Researchers scrutinized everything that was eaten and came away with the first hard evidence to support a long-held suspicion: Heavily processed foods could be a leading factor in America?s obesity epidemic.
The unusual clinical trial compared the volunteers? calorie consumption and weight gain when they ate a diet based on unprocessed ingredients and when they ate meals dominated by ultra-processed foods. Both daily menus had matching amounts of calories, fat, sugar, carbohydrates and salts, and diners said they were equally tasty and satisfying.
Yet the volunteers chose to consume an average of 508 additional calories per day on the ultra-processed diet. After two weeks, they weighed an average of 2 pounds more than their counterparts who had dined on unprocessed foods.