If you thought calories and fat were all you had to think about when it comes to eating for weight loss, think again. According to a new study published in the International Journal of Obesity, when you eat is just as important as what you eat.

Researchers studied 420 overweight participants who were following a 20-week weight-loss program in Spain. The participants were divided into two groups: early-eaters and late-eaters, according to the time at which they chose to eat their main meal, which in this population was lunch. Early-eaters ate lunch any time before 3 p.m. and late-eaters ate any time after 3 p.m. This meal accounted for 40 percent of the total daily calories consumed.

"Our results indicate that late eaters displayed a slower wight-loss rate and lost significantly less weight than early eaters," study author Frank Scheer said.

Surprisingly, total daily calories consumed and expended, level of appetite hormones and sleep duration was similar between the groups. But late-eaters had a lower insulin sensitivity, which is a risk factor for Type 2 diabetes.

Researchers also found that late-eaters typically consumed fewer calories at breakfast and were more likely to skip breakfast altogether.

The study's results suggest that the timing of high calorie meals may impact metabolic rate, which makes sense. After all, regular snacks or meals every three to four hours are important to fuel your metabolism, help prevent blood-sugar crashes and prevent binge eating.

When do you eat your largest meal of the day?

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