Every food has some calories, so negative calorie does not mean no caloric food.
Negative calories are foods which need more calories than they contain to get digested.
Digestion of food requires energy. Negative calories foods are difficult to digest and require more energy for digestion.
The digestion of these foods is harder for the body and results in burning of the fat. Hence these foods are also called fat burning foods.
It is useful to involve negative calories food to diet to reduce weight without starving.
Negative calorie foods produce enzymes which help in breakdown of extra calories along with calories in these foods.
Asparagus, broccoli, cabbage, cauliflower, carrot, celery, garlic, cucumber, hot chili, onion, radish, spinach, turnip, lettuce, tomato, peppers are some vegetables which are natural negative caloric food.
Apricot,blackberry,grapefruit,guava,lemon,honeydew melon,peaches,plums,raspberry,strawberry,watermelon are some fruits which are natural negative caloric food.
Negative caloric foods can be eaten generously and help to lose fat