You’ve probably heard the term “negative calories” to describe some fruits and vegetables. In a nutshell, the theory is that these high-fiber and low-calorie foods actually require more calories to break down than they contain. Celery, asparagus, beet, broccoli, cucumbers, onions, apples and even mangoes make the list.
But is the negative calorie theory true?
The calories required to release nutrients from food are calculated in the Thermic Effect of Food (TEF). While the TEF usually is in the 10% range for most foods, it can go as high as 20%. But it never nears 100%, or surpasses it – as the negative calorie theory would imply.
A wedge of cucumber, for example, has 20 calories. If the TEF for cucumbers is 20%, then you’re still left with a net gain of 16 calories. No negative calories there.
In fact, the FDA fined Nestle and Coca-Cola $650,000 in 2007 for describing their green tea drink as “negative calories” without being able to produce any research to support their claim. Opps.
So, no: There are no such things as negative calorie foods. And the subsequently created Negative Calorie Diets are a bit misleading. If you ate plate after plate of mangoes, your stomach wouldn’t magically disappear. In fact, quite the opposite would happen.
Nonetheless, many so-called negative calorie foods are actually quite healthy. Just realize that you are gaining calories while consuming them.






Isn’t it so, that proteins were suppose to be “negative calorie foods” ?
As Body needs more energy to metabolize than it receives from the intake, as it is with Carbohydrates?
Regards,
Marco