Processed foods lead to weight gain, but it's about more than calories

In the first study of its kind, scientists have shown that eating ultra-processed foods leads to weight gain in human volunteers in as little as 2 weeks.

There are plenty of studies in mice linking processed foods to problems such as?obesity?and?intestinal inflammation.

But mice are not people, as critics of such studies are quick to point out.

In humans, researchers have reported associations between processed foods and health outcomes, such as an increased risk of developing obesity, cancer, autoimmune conditions, and even death.

Yet, ultra-processed foods make up a staggering 57.9% of energy intake in the United States.

According to the NOVA food classification system, ultra-processed foods include soft drinks, packaged snacks, meat nuggets, frozen meals, and foods high in additives and low in unprocessed ingredients.

"Previous studies have found correlations between ultra-processed food consumption and obesity," Kevin D. Hall, from the National Institute of Diabetes and Digestive and Kidney Diseases in Bethesda, MD, which is part of the National Institutes of Health (NIH), explained to Medical News Today.

Hall and his colleagues now present the results of a controlled clinical trial, comparing the effects of unprocessed versus ultra-processed foods on humans in the journal Cell Metabolism.