Processed or ultra-processed foods often contain refined carbs, added sugars, and artificial fats that disrupt metabolism. A 2019 landmark study published in Cell Metabolism, which is a cell press journal, found that people who consumed ultra-processed diets ate about 500 extra calories per day and gained weight, compared to those eating unprocessed foods, even when the meals were matched for calories, sugar, fat, and nutrients.
Processed foods also tend to spike blood sugar and insulin levels. As per NIH study, these are known factors that promote fat storage, especially around the abdomen. So, even after cutting calories, if someone is consuming ultra-processed food, then they’re most likely ruining their hard efforts given on exercising.