What is the approximate energy content per 100 g of lipids?

• A. 1600 kJ
• B. 1700 kJ
• C. 1000 kJ
• D. 3700 kJ

Answer: (D)

Lipids have the highest energy density among macronutrients. Each gram of fat provides about 9 kcal, which is roughly 37 kJ. If you have 100 g of lipids, the energy content is about 100 × 37 kJ ≈ 3700 kJ. This is why the approximate energy content per 100 g of lipids is about 3700 kJ. For context, carbohydrates and proteins supply about 17 kJ per gram (4 kcal/g), so 100 g of those would give around 1700 kJ, highlighting why fats yield much more energy per gram.