It may feel chic and European to dine at 9 p.m., but it could mean a bigger waistline over time. Here’s what you need to know.
There are a surprising number of everyday habits that could be contributing to weight gain, from drinking diet soda to not getting enough sleep. But here’s an easy one to control, according to new findings presented at the SLEEP 2017 conference.
Apparently, people who make a habit of eating meals later in the day increase their chance of obesity, even if they’re not eating any more than they would have earlier.
For the meal-timing study, researchers created two conditions—daytime eating that consisted of three meals and two snacks consumed between 8 a.m. and 7 p.m., and delayed eating that consisted of three meals and two snacks eaten between noon and 11 p.m. All participants had a healthy body mass index (BMI), and for the study they ate the same diets and slept for nearly seven hours every night. A fitness regimen was included for both groups.
After an 18-week period, the delayed eaters showed weight gain, slower metabolism, and increases in insulin and cholesterol levels, and the earlier eaters did not. Late-day eating was also associated with “metabolizing fewer lipids and more carbs,” study author Namni Goel, PhD, of the University of Pennsylvania Perelman School of Medicine told MedPage Today. “The study provides some of the first experimental evidence that prolonged delayed eating promotes weight gain and a negative profile for fuel oxidation, energy metabolism, and hormonal markers, in normal weight adults.”
And Dr. Goel would expect to see even larger effects in people who already obese or have metabolic syndrome.
It’s been previously established that a lack of sleep can cause weight gain, but this study also showed that meal timing can affect sleep, so eating late is a one-two punch that leads to packing on pounds. Researchers don’t yet understand why metabolism rates are affected by eating later, but they do know that people suffering from insomnia or who sleep erratic hours because of their jobs are often most affected by the consequences of late-day eating.
Dr. Goel hopes more research can be conducted on a much larger scale, with a larger variety of participants, but for now she encourages us to stick to an earlier dining schedule—starting with breakfast around 8 a.m.—to prevent unnecessary weight gain.
“This is a behavioral intervention that, I think, could be beneficial and would be easy to implement in one’s own life,” Dr. Goel says. “Even if people can’t do it all of the time, most of us could do it 80 percent of the time.”