Final answer:
Equivalent to 1,000 small calories, the Calorie (with a capital 'C') or kilocalorie (kcal), is the unit used to measure the energy content in food, which is also equal to 4,184 Joules.
Step-by-step explanation:
The unit equivalent to 1,000 calories used to measure the energy in food is the Calorie, also known as a kilocalorie or kcal. One Calorie (with a capital 'C') is equivalent to 1,000 small calories (cal), which is the amount of energy needed to heat 1 kilogram of water by 1 degree Celsius. Additionally, this is equal to 4,184 Joules (J), the SI unit of energy.
In nutritional contexts, when we talk about the caloric content of food, we are usually referring to Calories, or kilocalories, as a measure of the energy provided by the digestion of foods. This is important to understand for maintaining a balanced diet and managing energy intake.