Background: Observational studies show associations between breakfast skipping, reduced satiety, and poor sleep quality; however, intervention studies are lacking.
Objective: The purpose of this study was to examine the effects of consuming breakfast compared with breakfast skipping on appetitive, hormonal, and neural markers of appetite and satiety; ad libitum food intake; and exploratory measures of sleep health in young adults.
Methods: Thirteen adults [aged 23.5 ± 0.9 y (mean ± SEMs); body mass index (kg/m2): 23.6 ± 0.6] completed the following randomized crossover-design study. Participants consumed a high-protein breakfast ("Breakfast"; 340 kcal, 30 g protein, 36 g carbohydrate, 9 g fat) or skipped breakfast ("Skip") for 7 d/treatment. On day 7, an 8-h clinical testing day was completed including assessments of hunger, fullness, desire to eat, prospective food consumption (PFC), related hormones, food cue-stimulated functional magnetic resonance imaging brain scans, and ad libitum evening food intake. Sleep quantity and quality were assessed with 7-d actigraphy, 7-d sleep diaries, and sleep-related hormones.
Results: Morning and daily hunger, desire to eat, PFC, and ghrelin decreased, whereas fullness increased after the Breakfast pattern compared with after the Skip pattern (all, P < 0.05). No difference in peptide YY (PYY) concentrations were detected. Hippocampal, parahippocampal, and middle frontal gyrus activations were reduced after the Breakfast pattern compared with the Skip pattern (all, P < 0.01). Although no differences in daily food intake were observed, the Breakfast pattern reduced evening intake of high-carbohydrate and high-fat foods (P < 0.05), whereas evening sugar intake tended to be reduced compared with the Skip pattern (P = 0.085). Although Breakfast led to shorter total sleep time (TST) compared with Skip (P < 0.05), no difference in sleep efficiency (TST/sleep period) was detected. Perceived sleep quality and sleep onset tended to improve after Breakfast compared with after Skip (P = 0.060 and P = 0.07, respectively).
Conclusion: Breakfast consumption improved appetite, satiety, and diet quality and may support some aspects of sleep health in healthy young adults. This trial was registered at clinicaltrials.gov as NCT03031132.
Keywords: appetite; breakfast; satiety; sleep; snacking.