What is energy density?

• A. Calories per serving
• B. Kilocalories per gram of food
• C. Grams of fat per serving
• D. Total energy per day

Answer: (B)

Energy density describes how many calories are packed into a given weight of food, expressed as kilocalories per gram. This helps compare foods by how energy-rich they are per unit of weight, regardless of how much you decide to eat. For example, 100 g of watermelon has far fewer calories than 100 g of almonds, even if you eat similar portions, because water and fiber dilute the energy in the watermelon. That per-gram measure shows why some foods can fill you up with relatively few calories while others deliver a lot of energy in a small amount of food.

Thus the statement that energy density is kilocalories per gram of food captures the definition precisely. Calories per serving depend on portion size, total energy per day sums daily intake, and grams of fat per serving measures a nutrient, not the energy density of the whole food.