Which macronutrient has a caloric content of 9 kcal/g?

Fat is the macronutrient that has a caloric content of 9 kcal/g. This high energy density means that fats provide more than twice the energy per gram compared to carbohydrates and proteins, which both provide approximately 4 kcal/g. This characteristic makes fats an important source of energy in the diet, particularly for athletes who may require a greater caloric intake to fuel their performance.

Fats also play a crucial role in the absorption of fat-soluble vitamins (A, D, E, and K) and contribute to cellular structure and hormone production. The understanding of fat's caloric content is essential for nutrition planning, particularly in sports medicine, where adequate caloric intake is vital for optimal performance and recovery.

In contrast, carbohydrates and proteins have a considerably lower caloric content, and alcohol, while it also provides 7 kcal/g, is not categorized as a macronutrient in the same sense as the others since it does not contribute to the body's growth and maintenance in a nutritional context. Therefore, knowing that fat provides 9 kcal/g highlights its significance in energy provision in dietary planning.