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Metabolic and neural responses to ultraprocessed foods: a randomized, controlled, crossover study
The full study comprised 57 participants; of these, 32 completed both metabolic sessions in a randomized crossover design and 52 completed the functional magnetic resonance imaging (fMRI) session (Extended Data Fig. 1). Every participant who completed the metabolic sessions also completed the fMRI session. The overall participant sample was 31.6% male, with a mean age of 26.21 ± 6.85 years and body mass index (BMI) of 22.75 ± 1.87 kg m−2 (Extended Data Table 1). Participants’ habitual energy intake on average comprised 54.4 ± 18.4% UPFs, similar to the national average of 55.0% (ref. 2). Additional participant characteristics are described in Extended Data Table 1. Exclusions and final analytic samples for each modality are summarized in the CONSORT diagram (Extended Data Fig. 1). Acute metabolic effects of UPFs and non-UPFs To investigate the effect of processing level on post-ingestive metabolic response to foods with matched nutrient content, 32 participants consumed, and were required to finish within 10 min, ~300 kcal nutritionally matched meals composed entirely of either UPF or non-UPF while undergoing 4 h (50 min baseline followed by a 3 h postprandial period) of whole-room indirect calorimetry (WRIC) and concomitant blood collection by intravenous catheter (Fig. 1a). The non-UPF...
