The Science of Fasting
We’ve all heard of the latest fad diets:
gluten-free eating plans supposedly proven to help you lose weight fast.
What if we told you that the answer to losing weight, improving body composition, and feeling better overall might not even really be about dieting, but instead just skipping meals every once in a while? For some, intermittent fasting, or going a longer period of time — usually between 14 and 36 hours — with very few to no calories, can actually be a lot easier than you may think, and the benefits might be worth it. If you think about it, all of us “fast” every single day — we just call it sleeping. Intermittent fasting just means extending that fasting period, and being a bit more conscious of your eating schedule overall. But is it right for you? And which method is best?
The Science of Fasting
As far back as the 1930s, scientists have been exploring the benefits of reducing calories by skipping meals. During that time, one American scientist found that significantly reducing calories helped mice live longer, healthier lives. More recently, researches have found the same in fruit flies, roundworms and monkeys. Studies have also shown that decreasing calorie consumption by 30 to 40 percent (regardless of how it’s done) can extend life span by a third or more. Plus, there’s data to suggest that limiting food intake may reduce the risk of many common diseases. And some believe fasting may also increase the body’s responsiveness to insulin, which regulates blood sugar, helping to control feelings of hunger and food cravings.
The five most common methods of intermittent fasting try to take advantage of each of these benefits, but different methods will yield better results for different people. “If you’re going to force yourself to follow a certain method, it’s not going to work,” says trainer and fitness expert Nia Shanks. “Choose a method that makes your life easier,” she says. Otherwise, it’s not sustainable and the benefits of your fasting may be short-lived.
So what’s the first step in getting started? Each method has its own guidelines for how long to fast and what to eat during the “feeding” phase. Below, you’ll find the five most popular methods and the basics of how they work. Keep in mind, intermittent fasting isn’t for everyone, and those with health conditions of any kind should check with their doctor before changing up their usual routine. It’s also important to note that personal goals and lifestyle are key factors to consider when choosing a fasting method.