Dietary Energy – a Story of Calories

So, what is a calorie anyway?  A calorie is a unit of energy.

1 calorie equals the energy needed to raise the temperature of 1 gram of water 1 degree Celsius.  Dietary energy refers to the amount of energy released when we metabolize what we eat, and it is expressed in calories per gram (or kcal/g).

Carbohydrates and protein provide 4 kcal/g

Ethanol provides 7 kcal/g

Fat provides 9 kcal/g