What is the energy yield of carbohydrates?

The energy yield of carbohydrates is generally standardized at 4 kilocalories per gram. This value is derived from the complete oxidation of carbohydrates during metabolism, where they are broken down into glucose and other simple sugars that the body can use for energy. This energy is then available for various bodily functions, such as maintaining basal metabolic processes and supporting physical activity.

Understanding that carbohydrates primarily serve as a quick energy source is important in nutritional science and dietetics. In contrast, fats yield about 9 kilocalories per gram, which is considerably higher due to their complex structure and higher energy content, while proteins yield 4 kilocalories per gram as well, but they also play significant roles in tissue repair and growth.

The other options reflect incorrect values for carbohydrates and do not align with established nutritional science regarding energy production. Recognizing the energy yield of various macronutrients is fundamental for dietary planning and understanding how to meet energy needs effectively.