Well, yes and no. Digesting food burns calories. And it's true that a few foods, such as grapefruit and celery, contain fewer calories than it takes to digest them. So, when you eat these foods, you actually burn more calories than you take in. Thus, the term "negative-calorie foods."
Theoretically, the more negative-calorie foods I eat, the more weight I lose! How great is that? Now all I need is a job that pays me more the less I do, and a bank account that gets bigger the more I spend!
Unfortunately, it doesn't work that way. Here's why: When nutritionists estimate how many calories you should eat, we're already taking into consideration how many calories you burn chewing and digesting your food. The "negative-calorie diet" essentially subtracts those calories twice. That's the kind of accounting that will make you bounce checks (or get you a really good job on Wall Street).
How Negative-Calorie Foods Help You Lose Weight
But will eating a whole bunch of celery and grapefruit speed your weight loss? Only if you eat them instead of brownies and potato chips. In other words, you can't eat a brownie and then burn off the calories by chasing it with a hundred sticks of celery. The only way to make this work is to eat the hundred sticks of celery first. Then, with any luck, you'll be too full to eat the brownie.
Replacing high-calorie foods with low-calorie foods will help you lose weight because it reduces your overall calorie intake. Of course, you can also lose weight by exercising, which burns calories. But digesting negative-calorie foods does not constitute an exercise program. Take it from me: A half-hour spent on the treadmill or bike is going to burn a lot more calories than a half-hour spent digesting celery.
Those lists of negative-calorie foods you'll find on the Internet are simply lists of low-calorie foods. And, if you're dieting, these kinds of foods are your friends. To that end, here's a list of "negative-calorie foods." But take this list with a grain of salt: I'm afraid that a negative-calorie diet is, indeed, to good to be true.
See also: "How to Create Your Own Best Diet."
For more by Monica Reinagel, MS, LDN, CNS, click here.
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