We have all heard it so many times – junk food (“ultra-processed food”) makes you fat. But why?? There is a scientific answer now, from a study comparing junk food to normal food consumption. Bottom line: junk food makes you fat simply because it makes you eat more calories in a given meal. And that’s because it packs more calories in a smaller package.

Look at the shocking graph here, that’s all you need to see: junk food consumers gained 1 kg over 2 weeks, while consumers of unprocessed foods even lost a comparable amount of weight.

The study design was ingenious: the macro-nutrient proportions were kept the same for the two diet choices (fats, carbs, proteins, and fiber). Participants could eat as much as they wanted for each diet. And they ate more calories per unit of time when presented with junk food. When the roles were reversed, the outcomes were also reversed, previous weight gainers lost weight again while the new junk food converts gained some.

Food for thought.