A
calorie is used throughout the food and dieting world as a unit representing the energy provided by food you need to eat, or the amount of energy you expending during exercise and daily living. Technically speaking, one calorie is the amount of energy required to increase the temperature of one gram of water by 1 °C.
The food we eat is metabolized or
burned by the body. This process converts the food into energy (generally through breaking it down to
glucose.
Fat has much more energy (calories) per ounce than carbohydrate and protein. There are:
- 9 calories in each gram of fat
- 4 calories in each gram of protein
- 4 calories in each gram of carbohydrate (except for fiber which isn't metabolized)