When offered ultra-processed foods, people ate more quickly and took in an average of 500 more calories per day than when they were offered unprocessed foods. Participants gained roughly 1 kilogram during the trial’s junk-food phase and lost roughly the same amount during the whole-foods phase.

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When offered ultra-processed foods, people ate more quickly and took in an average of 500 more calories per day than when they were offered unprocessed foods. Participants gained roughly 1 kilogram during the trial’s junk-food phase and lost roughly the same amount during the whole-foods phase.