Here’s a new diet tip: Stay away from highly processed foods.
People gained more weight and consumed more calories from ultraprocessed foods than they did from a minimally processed diet. That’s the upshot of a recent National Institutes of Health study that tracked dietary habits and body changes among adults.
It was the first randomized, controlled study assessing the effects of highly processed ingredients such as high fructose corn syrup, flavoring agents and hydrogenated oils. While some prior research had found an association between processed food and health issues, the new study was different because it randomly assigned participants to eat certain foods and tracked the results.
For the study, adult volunteers spent two weeks on each diet. One of the diets included minimally processed food such as oatmeal with nuts, bananas and skim milk. The other was based on processed foods, including bacon and a bagel with cream cheese. The processed and unprocessed meals had similar amounts of nutrients including sugar, fat and carbohydrates.
The findings clearly showed that highly processed food caused participants to eat more and gain weight.
Participants ate as much or as little as they wanted, and the researchers found a pattern: On the processed diet, people ate faster and consumed 500 more calories a day. The average weight gain for the processed food diet was two pounds, while people lost an average of two pounds eating the unprocessed food.
Next, researchers want to know more about how processed foods affect eating behaviors. Until then, think about skipping that bagel and reaching for oatmeal instead.