Late-night eating habits tied to slower calorie burn, increased appetite

A common perception about meal timing and human health is that late-night dinners and midnight snacks are best avoided, and a new study has offered some compelling insights into why. The study compared late-night eating to a regular meal schedule and found some marked differences in terms of obesity risk, revealing effects on appetite, adipose tissue formation, and energy expenditure throughout the day.

Led by scientists at Brigham and Women’s Hospital, the new study sought to comprehensively examine some of the bodily effects of eating late at night. Some interesting studies have shed light on the relationship between meal timing and human health, including some that highlight the anti-aging potential of eating during the dayand one last month that showed how a a big breakfast can help suppress your appetite in obese subjects.

Bringing their expertise to the table, the authors of the new study focused on three key drivers of body weight: calorie intake, calorie burn, and molecular changes in fat tissue.

“We wanted to test the mechanisms that may explain why eating late increases the risk of obesity,” explained lead author Frank AJL Scheer. “Previous research by us and others had shown that eating late is associated with increased risk of obesity, higher body fat, and lower weight loss success. We wanted to understand why.”

To find answers, scientists recruited 16 overweight or obese subjects who completed two feeding schedules in the laboratory as part of a randomized crossover study strictly controlled for factors such as posture, sleep, light exposure and activity. physical. Both feeding times featured the exact same meals, except that one protocol involved eating them about four hours later in the day.

At all times, the subjects provided regular blood samples, documented their levels of hunger and appetite, and had their body temperature and energy expenditure monitored. The scientists also collected adipose tissue biopsies to track how different meal times shaped molecular pathways associated with fat formation. And these measurements uncovered some compelling differences between the two feeding schedules.

Eating later was found to alter the appetite-regulating hormone ghrelin and reduce levels of the hormone leptin, which signals the brain that we’re full, thus increasing hunger levels during waking hours. When the subjects ate later in the day, they also burned calories more slowly and exhibited altered gene expression in fat tissue. These changes favored lipid storage, favoring fat growth.

“In this study, we asked, ‘Does the length of time we eat matter when everything else is held constant?'” said first author Nina Vujovic. “And we found that eating four hours later makes a significant difference in our hunger levels, the way we burn calories after eating, and the way we store fat.”

The research was published in the journal Cellular metabolism.

Font: Brigham and Women’s Hospital