Ultra-processed food and extra calories

Participants lived in a clinic and ate ad libitum; the two diets were matched for calories, sugar, fat, fibre and macronutrients. On the ultra-processed diet people ate 508 kcal a day more and gained 0.9 kg in two weeks, while on the unprocessed diet they lost 0.9 kg. The difference came from how much people served themselves, not from the composition.