Before skipping your next meal in the name of weight loss, read up on the recent studies that (literally) weighed the pros and cons of intermittent fasting
Can't stop gaining weight? Skip a meal here and there. Or skip meals for a whole day. No wait! Just eat more small meals, spread throughout the day. Actually, just eat kale!
Every week, there's new research about eating healthy or dieting. Unfortunately, a lot of it seems to contradict everything else you've read on the subject. This week was no different: A new study suggested that skipping meals leads to more belly fat and the types of metabolic changes linked to diabetes.
In the study, rodents forced to eat a restricted diet for five days (compared to mice allowed to eat steadily throughout the day) ended up gorging and gaining weight—especially around their mousey midsections. The calorie-restricted mice also showed unhealthy blood-sugar responses. (Here, 6 Reasons You're Not Losing Belly Fat.)
There's reason to believe the findings translate to people, says Martha Belury, Ph.D., co-author of the study and an energy metabolism researcher at Ohio State University. "There is evidence that people who skip meals struggle with weight control," she says. "Our study seemed to support that."
Asked to explain how cutting back on calories could lead to weight gain, Belury says skipping meals may lead to overdoing it at your next meal. That kind of behavior could spike your blood's levels of insulin, which in turn could trigger fat storage, she adds.
But additional research argues otherwise. Another mouse experiment—this one from 2014—found rodents who fasted for 15 or 16 hours every day dropped 12 percent of their body weight, enjoyed lower levels of inflammation, and were better protected against diabetes than mice who ate roughly the same amount of calories spread throughout the day. More research has hinted at similar benefits among people who fast. (See Ask the Diet Doctor: The Pros & Cons of Fasting for Weight Loss.)
So how do you square away all of this conflicting evidence? Belury points out that her study forced mice to eat less for five consecutive days. "If you did this meal-skipping for longer periods, or just one day a week, your body might adapt to the restriction in different ways," she says.
This might explain why people who lose weight with super-restrictive "crash diets" tend to put that weight back on just as quickly. That 2014 study found that the longer mice stuck with a restricted diet, the more they benefitted.
Of course, what you eat also matters. If you're skipping meals while also trying to follow a limited food plan—a vegan diet, say, or a juice cleanse—it's unclear how your body will react. Your distinct biochemistry also plays a role. "There are a lot of unanswered question," Belury says. (Stay on track by learning the 16 Diet Plan Pitfalls That Can Be Easily Prevented.)
New research may soon have answers. But while food and nutrition scientists sort out the ins and outs of calorie restriction and meal timing, you're better off spreading small, healthy meals and snacks throughout your day, Belury's study suggests. "In general, people who eat regularly are more likely to keep weight off than people who skip meals," she explains. So go ahead, grab a (healthy) snack. It won't derail your diet, promise!