What is a "calorie"?

A calorie is a unit of measuring energy. There are two types of calories used in popular culture: small calorie and large calorie.

Small Calorie(cal) is defined as the energy needed to raise the temperature of one gram of water by 1 degree Celsius at one atmospheric pressure.

The Large Calorie(Cal) is popularly used by the food industry. 1 large Calorie is equivalent to 1000 small calories and is used for measuring energy provided by food.

The calorie is an outdated and obsolete unit of measurement and the SI unit used is Joule. 1 small calorie is equal to 4.2 joules of energy.

A calorie is technically defined as a unit of energy needed to raise the temperature of 1 gram of water by 1 degree Celsius. However, most of us recognize this word as relating to food. How are the two related? Food is, in its most basic form, a source of energy for your body.

Your body burns energy through its basic functions every day, and so it needs these calories to fuel itself. If not enough calories are consumed, the body resorts to burning stored fat to keep itself going. If too many calories are consumed, the body converts that energy into fat in case it is needed later. Counting your daily input and output of calories is an essential part of weight loss.