Forty-five million Americans go on a diet each year, many of them after the overconsumption of the holidays, and as few as 5% manage to keep off the weight. About 70% of Americans are overweight or obese, according to The Washington Post.

Obesity causes major health problems and can shorten your life by increasing the risk for diabetes, heart attacks, strokes, and many cancers. Yet experts clearly document that the dozens of diets out there simply don’t work because people feel deprived, long for their favorite foods, and eventually fall off the food wagon. However, there is one easy-to-follow and effective weight loss plan that has been shown to work extremely well. It is called intermittent fasting.

“Recent research shows why intermittent fasting may be an effective way to help people lose weight, keep it off, and slow down or reverse the diseases and disabilities that being overweight can cause,” said Dr. Gabe Mirkin, a noted sports medicine physician and author of "The Healthy Heart Miracle."

Intermittent fasting means that you limit the times you eat for a set number of hours during the day, or days per week, or days per month, Mirkin explains, adding that a study from the University of South Florida found that intermittent fasting works by “flipping the metabolic switch.” After not eating for 12 hours or so, your body starts to burn body fat instead of using glucose, its natural energy source. The metabolism switch means that your body uses stored body fat for energy after you have fasted, and you start losing weight.

There are many types of intermittent fasting, says Shawn Stevenson, author of the soon-to-be released book "Eat Smarter." Stevenson, a nutritionist, researcher, and host of the top-ranked podcast "The Model Health Show," uses cutting edge science to show how certain types of food and when we eat them can boost our metabolism, improve cognitive performance, and even enhance our relationships.

He explains that some versions of intermittent fasting involve eating one day and then fasting the next, while others involve eating for five days and fasting for two.

“One of the things I’ve seen most people have success with is simply creating a fasting window of 12 to 16 hours,” Stevenson says. Mirkin adds that he and his wife Diana, stop eating after 6 p.m. until the next morning.

The really good news about intermittent fasting is that you are not restricting or counting calories, although making good food choices will improve your success. By eating in your recommended window of time, “your metabolism will literally be working more efficiently and be more acclimated to burning fat for fuel,” Stevenson explains.

Not only that, according to a report from the International Association for the Study of Obesity, intermittent fasting is more effective in retaining muscle mass than daily calorie restriction. Muscle tissue is valuable, says Stevenson, because having more muscle on your frame enables you to burn more calories both during activity and at rest.

Studies show that intermittent fasting improves brain health. Data published in the Journal of Molecular Neuroscience showed that this way of eating stimulates new brain cells and improves the performance of the neurons you already have.

Finally, Stevenson points out in his book, which will be available Dec. 29, that intermittent fasting reduces the risk of disease and slows down the aging process.

“Creating your own blocks of time when you’re eating and not eating is one of the most powerful tools in your superhero utility belt,” he says.