Question

How many calories are there in one litre of water

• A. 1000 calories
• B. 100 calories
• C. 1 calories
• D. None

Answer 1

The Correct Option is D

Step 1: Understand the question
The question asks how many calories are present in one litre of water. Here, "calories" refers to energy content in food or drink, not the heat capacity of water.

Step 2: Nutritional perspective
Calories in food and beverages come from carbohydrates, proteins, and fats. Pure water does not contain any of these nutrients. It is simply H₂O with no energy value for the body to extract. Therefore, water provides **zero nutritional calories**.

Step 3: Clarify misconception about heat calories**
In physics, water does have a heat capacity (1 calorie raises the temperature of 1 gram of water by 1°C). But this is a scientific unit of heat energy, not the "dietary calories" measured in food. The question here refers to dietary calories, so we must stick to that definition.

Step 4: Final justification
Since pure water contains no proteins, fats, or carbohydrates, its calorie content is zero. Thus, one litre of water has no calories.

Final Answer: The correct option is (D) None.