How is energy typically measured?

Energy is primarily measured in calories, especially in the context of food and nutrition. The calorie is a unit that quantifies the amount of energy provided by food upon consumption. It reflects the energy needed to raise the temperature of one gram of water by one degree Celsius. In the field of nutrition, the term "calories" often refers to kilocalories (1 kcal = 1,000 calories), which represent the energy content in larger quantities of food.

While joules are also a valid unit for measuring energy and can be used in scientific contexts, calories are more commonly used in dietary and weight management discussions, making them more recognizable and practical for everyday use. Liters, on the other hand, measure volume, and grams measure mass; neither directly relates to the measurement of energy in food. Therefore, the use of calories as a standard for expressing energy in nutrition effectively conveys the energy content of foods to individuals seeking to manage their dietary intake and overall energy balance.