Is Fasting the Fastest Way to Lose Weight? A New Study Says Yes
June 01, 2017
Eat just 500 calories in a day, which amounts to little more than a cup of yogurt, a salad with hard-boiled eggs or lean chicken, and some vegetable soup. But what if you knew you could go back to your regular menu of meat, pasta, and sandwiches for the next few days—would that make the “fasting day” more bearable?
This is how the Intermittent Fasting, or 5:2 diet, works. You eat whatever you’d like five days a week, and then stick to a starvation-level 500 calories the other two. “There are also variations on this diet in which you fast for certain hours of the day,” explains Audrey Banich, RD, a nutritionist with Indiana University Health. “It all comes down to eating fewer calories over the course of a week.”
Of course, adds Banich, this doesn’t mean you have permission to binge on the five regular days, shoveling in all the cake, candy, and cheeseburgers you skipped while fasting. “You still need to eat a normal, healthy diet on the other days,” she says.
While this may seem like an extreme version of yo-yo dieting, research is showing that it does work—for some people. A newly released study found that people on the intermittent-fasting diet lost a similar amount of weight over six months as those on a traditional diet that restricted calories all seven days a week, and reaped similar cardiovascular benefits. However, the intermittent-fasting diet had a higher dropout rate. “If you like to snack a lot, and tend to eat several small meals over the course of the day instead of two or three big meals, this would be a very difficult diet to adhere to,” says Banich. However, she adds, people who know they are too busy to sit down to regular meals a few days a week might find it works well with their schedule.
One potential benefit of the intermittent-fasting diet is its possible effect on brain health. Researchers at the National Institutes of Health’s National Institute on Aging are looking into the theory that fasting a couple of days a week can kick-start the brain into activating anti-aging processes, which may help prevent Alzheimer’s disease and other types of dementia.
Whether your goal is losing weight or keeping your brain sharp, it is crucial to speak with a nutritionist or physician before embarking on this diet, says Banich. “If you’re only going to eat 500 calories on two days, you have to make sure they are the right 500 calories,” she says. “Fruits, vegetables, and lean proteins are most important, and you have to watch your liquid calories, which won’t fill you up at all.”
Also, make sure to schedule your fitness plan around your fasting days, Banich suggests. “You need to time your meals so that you are not starving during a workout, which could cause you to pass out or injure yourself.”