Learn how food calories are measured.
Food calories are measured by a device called a bomb calorimeter, a sealed compartment in which a specific weight of food is completely burned.
When calories are specified for a food, this translates into the potential energy (heat) that the food can generate when ingested. Each food calorie is equal to the amount of energy needed to raise the temperature of one kilogram (or one liter or 2.2 pounds) of water by 1 C at one atmospheric pressure.
Since the calculation is based on a kilogram (1,000 grams), a food calorie is a thousand times as much as a normal calorie (unit commonly used in physics and chemistry).
Overconsumption of calories is a common problem. If the body does not use them, they are stored as glycogen reserves and fat. More of the body's calorie consumption should come from complex dietary carbohydrates (starches) than simple carbohydrates (sugars) because simple carbohydrates tend to be empty or pure calories (fuel) that contain more than enough fuel but not enough of the other substances necessary to life.
Below is listed the number of calories needed daily by the human body, based on a composite of sources:
|Age range||Weight in pounds||Calories needed||Weight in pounds||Calories needed|
Age range|Weight in pounds|Calories Needed|Weight in pounds|Calories needed