Eat more to weigh less? That’s the promise of the “negative calorie" solution to losing weight. Eat certain foods, like celery or cucumber, and you’ll burn more calories chewing and digesting them than what you’d actually gain from the food itself.
Claims like this are appealing because so many of us want to lose weight, but without having to do the hard work that makes it possible. Unfortunately, the net loss from eating negative-calorie foods is so little as to be negligible.
For something we eat to be a source of negative calories, it must provide fewer units of energy than we expend in consuming it. This would seem impossible since all food contains calories. Plant foods are a potential candidate, however, because they largely contain carbohydrate in the form of cellulose, which our bodies can’t digest. We only gain a few calories from foods like celery or cucumber because they are mostly made of water and cellulose.
Considering that a you have to burn 3,500 calories to lose a pound of fat, chewing on celery (eight to 10 calories in a stalk) and cucumber (also eight to 10 calories in half a cup of slices) all day, however, would not only not get you very far, it certainly wouldn’t be healthy. Not to mention, you’d have little energy for anything.
Thirsty for a different kind of negative-calorie weight-loss fix? Recently, Coca-Cola Co. and Nestlé have jointly begun selling a carbonated tea called Enviga, which they say is a negative calorie drink. Coca-Cola and Nestlé claim that consuming this caffeinated drink, which contains an extract of green tea known as EGCG, speeds up metabolism, causing the drinker to burn calories.
Does it work? Like low-calorie, high water-content vegetables, a drink like Enviga could conceivably help you burn a few calories. Of note, though, the companies have cleverly avoided promoting the product specifically as a weight loss brew. Instead, they say it is a psychological boost.
So, what’s the bottom line? Substituting vegetables for cookies or chips is, of course, a good idea. But while it may be possible to expend a few more calories than you absorb eating celery or drinking a negative calorie drink such as Enviga, the key to losing weight, as always, is to exercise more and improve your overall diet.
- Robin Brett Wechsler
Modern Menus Staff Nutritionist
