Your body burns calories when you’re just lazing about, and it burns even more during certain times of the day. Here’s when you’re at your calorie-burning peak.

Here's When Your Body Burns the Most Calories at RestMR. WATCHARA POOTO/Shutterstock

Your body burns calories all day long to keep your organs humming, your blood pumping, and your lungs breathing—not to mention maintaining hundreds of other body processes. But a new study published in Current Biology reveals that there are times during the day when your metabolism really hums—and times when it slumps.

Researchers at Brigham and Women’s Hospital in Boston placed seven volunteers in a windowless room for three weeks, turning down the lights and waking them at different times while measuring their calorie use around the clock. The study revealed that we burn about 129 more calories—at rest—between 2 p.m. and 8 p.m. on average, compared to the early hours of the morning (2 a.m. and 8 a.m.). Even more intriguing is that the body seems to favor carbohydrates as an energy source early in the day and becomes more efficient at burning fat later in the afternoon.

Experts previously thought the body’s resting metabolism ran at a fairly steady rate around the clock; these findings indicate that calorie burn ebbs and flows with the body’s natural rhythms, reports lead study author, neuroscientist Jeanne Duffy, PhD, in a press release. One take-home message of the study seems to be yet another reason to avoid late-night snacking: The body’s energy demands are so low that those extra calories are likely to be converted to fat. Check out these 7 ways to cut calories if you’re trying to lose weight.

There may be implications for the best times to eat certain types of food—such as carbs in the a.m., more protein and healthy fats in the afternoon—but more research is necessary before anyone can make firm recommendations. Perhaps the most important lesson is that people should keep a regular eating schedule, according to Duffy. An irregular meal pattern can throw off the body’s rhythm, depress metabolism, and lead to weight gain, she says. Here are 23 more lazy ways to burn more calories every day.