Green Diets

In a negative calorie diet and several versions of this diet, dieters are to eat and drink food products that are nutritous but are said to have a negative caloric effect; i.e., they provide fewer food calories than the calories needed to digest them. The energy that the body needs to digest the food is usually given as a certain amount of calories, whilst the energy content of the food is given as kilocalories. There is, however, no such thing as a negative calorie food. The "negative calorie" foods allowed in this diet are mainly vegetables and fruits. including:

* Apples
* Asparagus
* Beets
* Blueberries
* Broccoli
* Green Cabbage
* Cantaloupes
* Carrots
* Cauliflower
* Celery
* Cranberries

This diet is criticized as being not a very realistic one. Opponents argue that these foods may be healthy, but the only way to get rid of calories is to use up more than you eat - a diet along with exercise is a way to see faster results. You should talk to your doctor to find a diet that is right for you.

Others criticize that such dieters use the concept of negative calories to justify eating unlimited quantities of such foods, and that doing so is not healthy.

Coca-Cola has announced a green tea drink, Enviga, which purports to contain 20-30 negative calories per can. It is uncertain as of yet how true the negative calorie claims are.