Study: Eating later in the day increases hunger, causes you to burn fewer calories and store more fat

Researchers at Brigham and Women’s Hospital found in a recent study that eating later in the day is likely to increase hunger.

Of those polled as part of the study, those who consumed meals later in the day, were hungrier, burned calories at a slower rate and stored more fat. The results of the study were published in the journal Cell Metabolism.

“In this study, we asked, ‘Does the time that we eat matter when everything else is kept consistent?’” author Nina Vujovic, a researcher in the hospital’s division of sleep and circadian disorders, wrote. “And we found that eating four hours later makes a significant difference for our hunger levels, the way we burn calories after we eat, and the way we store fat.”

During the study, 16 patients, who were classified as overweight, ate meals earlier in the day (8 a.m., 12 p.m. and 4 p.m.) whilst the others ate meals at the same intervals but four hours later.

Samples of blood and body fat tissue were taken from each participant, as well as levels of body temperature and how much energy they used. All participants were largely in good health and had no history of diabetes or shift work.

All participants logged their hunger and appetite, and researchers found that the participants who ate later reported double the levels of hunger than those who ate earlier. Those who ate later also burned 60 fewer calories and had lower levels of the hormone leptin, this is an appetite suppressant. 

“This study shows the impact of late versus early eating. Here, we isolated these effects by controlling for confounding variables like caloric intake, physical activity, sleep, and light exposure, but in real life, many of these factors may themselves be influenced by meal timing,” the lead author Frank Scheer told USA Today.

Scheer added, “In larger scale studies, where tight control of all these factors is not feasible, we must at least consider how other behavioral and environmental variables alter these biological pathways underlying obesity risk.”

Courtney Peterson, an associate professor of nutrition sciences at the University of Alabama at Birmingham, spoke to NBC News about the study – though Peterson did not have any involvement in this particular study.

“You have this internal biological clock that makes you better at doing different things at different times of the day,” Peterson said. “It seems like the best time for your metabolism, in most people, is the mid- to late morning.”