Eating breakfast and avoiding late-evening snacking sustains lipid oxidation

• Published in: PLoS biology Vol. 18; no. 2; p. e3000622
• Main Authors: Kelly, Kevin Parsons, McGuinness, Owen P., Buchowski, Maciej, Hughey, Jacob J., Chen, Heidi, Powers, James, Page, Terry, Johnson, Carl Hirschie
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27.02.2020; Public Library of Science (PLoS)
• Subjects: Biological clocks; Biology and Life Sciences; Biophysics; Body Mass Index; Body temperature; Breakfast; Carbohydrate Metabolism - physiology; Carbohydrates; Circadian rhythm; Circadian Rhythm - physiology; Circadian rhythms; Cross-Over Studies; Crossovers; Disruption; Eating; Eating behavior; Energy; Energy expenditure; Evening; Exercise; Feeding Behavior - physiology; Female; Food; Food habits; Gene expression; Human subjects; Humans; Industrialized nations; Lipid Metabolism - physiology; Lipid peroxidation; Lipids; Male; Meals; Meals - physiology; Medical research; Medicine and Health Sciences; Metabolic pathways; Metabolism; Middle Aged; Nutrient availability; Nutrition research; Obesity; Oxidation; Oxidation-Reduction; Oxidation-reduction reaction; Physical activity; Physical Sciences; Physiological aspects; Physiology; Pulmonary Gas Exchange - physiology; Research and Analysis Methods; Short Reports; Sleep; Sleep - physiology; Snacks; Substrate preferences; Substrates; Type 2 diabetes; Weight control; United States > US; Tennessee; Nashville Tennessee
• DOI: 10.1371/journal.pbio.3000622
• ISSN: 1545-7885; 1544-9173

Circadian (daily) regulation of metabolic pathways implies that food may be metabolized differentially over the daily cycle. To test that hypothesis, we monitored the metabolism of older subjects in a whole-room respiratory chamber over two separate 56-h sessions in a random crossover design. In one session, one of the 3 daily meals was presented as breakfast, whereas in the other session, a nutritionally equivalent meal was presented as a late-evening snack. The duration of the overnight fast was the same for both sessions. Whereas the two sessions did not differ in overall energy expenditure, the respiratory exchange ratio (RER) was different during sleep between the two sessions. Unexpectedly, this difference in RER due to daily meal timing was not due to daily differences in physical activity, sleep disruption, or core body temperature (CBT). Rather, we found that the daily timing of nutrient availability coupled with daily/circadian control of metabolism drives a switch in substrate preference such that the late-evening Snack Session resulted in significantly lower lipid oxidation (LO) compared to the Breakfast Session. Therefore, the timing of meals during the day/night cycle affects how ingested food is oxidized or stored in humans, with important implications for optimal eating habits.