Which macronutrient provides 9 kcal per gram?

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Multiple Choice

Which macronutrient provides 9 kcal per gram?

Fat is the macronutrient that provides 9 kcal per gram. This higher energy yield comes from its chemical structure—long hydrocarbon chains with many C-H bonds that release a lot of energy when fully oxidized in metabolism. Carbohydrates and proteins yield about 4 kcal per gram because they are more oxidized and have more oxygen in their structures, limiting the energy released per gram. Alcohol can supply around 7 kcal per gram, but it isn’t considered a macronutrient with essential biological roles, so the macronutrient giving 9 kcal per gram is fat.

Fat is the macronutrient that provides 9 kcal per gram. This higher energy yield comes from its chemical structure—long hydrocarbon chains with many C-H bonds that release a lot of energy when fully oxidized in metabolism. Carbohydrates and proteins yield about 4 kcal per gram because they are more oxidized and have more oxygen in their structures, limiting the energy released per gram. Alcohol can supply around 7 kcal per gram, but it isn’t considered a macronutrient with essential biological roles, so the macronutrient giving 9 kcal per gram is fat.

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