In trial, people lost twice as much weight by ditching ultraprocessed food
In a small randomized controlled trial, people lost twice as much weight when their diet was limited to minimally processed food compared to when they switched to a diet that included ultraprocessed versions of foods but was otherwise nutritionally matched.
The trial, published in Nature Medicine by researchers at University College London, adds to a growing body of evidence that food processing, in addition to simple nutrition content, influences our weight and health. Ultraprocessed foods have already been vilified for their link to obesity-largely through weaker observational studies-but researchers have struggled to shore up the connection with high-quality studies and understand their impact on health.
The ultraprocessed foods researchers provided in the new trial were relatively healthy ones-as ultraprocessed foods go. They included things like multigrain breakfast cereal, packaged granola bars, flavored yogurt cups, fruit snacks, commercially premade chicken sandwiches, instant noodles, and ready-made lasagna. But, in the minimally processed trial diet, participants received meals from a caterer rather than ones from a grocery store aisle. The diet included overnight oats with fresh fruit, plain yogurt with toasted oats and fruit, handmade fruit and nut bars, freshly made chicken salad, and from-scratch stir fry and spaghetti Bolognese.