c. Sort of
c. Sort of
To determine how many calories there are in a certain amount of food, that food is placed in a chamber where it is burned to ash, and the heat generated is measured. The chamber has the rather intriguing name of “bomb calorimeter.”
That’s not a bad way to measure how much energy there is in the food, but it’s not at all a good way to determine how much energy you will get out of the food. For example, the same amount of carbohydrate and protein has the same amount of “bomb calorimeter” calories, but the digestion and utilization of protein requires about twice as much energy as the digestion and utilization of carbohydrates. That means that you’ll get less usable energy from a protein dish than you would from same amount of carbohydrates.
There are actually many factors that determine how many of the potential calories in the food you eat are used as energy in your body, stored in some form, or simply eliminated. Those factors vary by individuals, over time, and in relation to your health. That all adds up to the fact that it’s not the number of calories stated on the package that’s important to understand, it’s how your body is likely to respond to them.