Calorie

A unit of energy. One calorie is the amount of energy needed to raise the temperature of 1 gram of water by 1°C. However, the term calorie is also used in medicine and dietetics to mean kilocalorie, a larger unit equal to 1,000 calories. Normally, when calorie intake matches the amount of energy expended, body weight remains constant. If intake exceeds expenditure, weight is usually gained; if expenditure exceeds intake, weight is usually lost. In general, fats contain the most calories. Energy can also be measured in joules: 1 calorie equals 4.2 joules. (See also calorimetry; diet and disease.)

 

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