Worldwide, more than 650 million people are obese and 1.9 billion are overweight according to the WHO, or 39% of adults over 18 years old. In France, obesity affects 17% of adults. A pathology that significantly increases the risk of diabetes, cancer, cardiovascular disease and other potentially fatal diseases. In adults, obesity is defined by a BMI of 30 or more. And according to a study published in the journal Cell Metabolism, the risk of obesity could be aggravated by the time at which one eats his dinner before going to bed. If this finding was already known, researchers at Brigham and Women’s Hospital wanted to understand why.
Indeed, eating (too) late reduce calorie burning, may increase hunger and cause changes in fatty tissue, which may contribute to weight gain. A late dinner could also impact the appetite-regulating hormones leptin and ghrelin.
I am so happy and proud to be coauthor in this study lead by Frank Scheer and Nina Vujović, in @Cell_Metabolism
Which show converging mechanisms by which late eating may result in positive energy balance and increased obesity risk.https://t.co/nWtuQKYvwM— Marta Garaulet (@martagaraulet) October 5, 2022
“In this study, we asked, ‘Does it matter when we eat when everything else is consistent? And we found that eating four hours later made a significant difference to our hunger levels, the way we burn calories after eating, and the way we store fat.”says Professor Nina Vujovic, lead author of the study.
Better to have dinner at 6 p.m. than at 10 p.m.
They looked at 16 overweight or obese patients between the ages of 20 and 60. They completed two laboratory protocols:
- one where dinner was taken early, with a strictly scheduled time around 18 hours,
- and another identical meal, taken four hours later, around 10 p.m..
Two to three weeks before starting each program, patients went to bed and woke up at the same time. At the same time they documented their hunger and appetite, provided regular blood samples and had their body temperature and energy expenditure measured.
The results showed the impact of a meal taken after 10 p.m. on hunger and on the appetite-regulating hormones leptin and ghrelin:
- The levels of the hormone leptin – which signals satiety – were lower in the 24 hours following a late meal compared to those who ate early => Concretely, eating later tends to be less satiating.
- Conversely, the levels of ghrelin (hormone that stimulates the appetite) were higher the day after a late meal => Concretely, eating later increases the desire for food upon waking.
- The researchers also found that people who dined late burned calories more slowly.
“This study shows the impact of late feeding compared to early feeding. Here we have isolated these effects by controlling for variables such as calorie intake, physical activity, sleep and light exposure, but in real life many of these factors can themselves be influenced. by meal times”concluded Professor Frank AJL Scheer, co-lead author.
Sources:
- Late isocaloric eating increases hunger, decreases energy expenditure, and modifies metabolic pathways in adults with overweight and obesity, Cell MetabolismOctober 4, 2022
- Eating late increases hunger, decreases calories burned, and changes fat tissueBrigham and Women’s Hospital, October 4, 2022