Which unit is commonly used to measure energy?

Kilocalories are commonly used to measure energy, particularly in the context of nutrition and diet therapy. This unit is often more practical in everyday life when discussing dietary energy. One kilocalorie (commonly referred to simply as a "calorie" in food contexts) is defined as the amount of energy required to raise the temperature of one kilogram of water by one degree Celsius.

In nutritional contexts, kilocalories provide a clearer understanding of energy content in food, as they account for the larger amounts of energy consumed in an average diet. While other units like joules and calories are technically accurate, kilocalories align better with the average energy needs and consumption levels of individuals, making this unit especially useful for dietitians and nutritionists who are advising clients on energy intake.

Joules, calories, and kilojoules are valid units for measuring energy, but kilocalories stand out as the standard in nutrition labels and dietary guidelines, ensuring clarity and consistency when discussing energy consumption from foods.