Final answer:
Fat is the macronutrient that contains 9 calories per gram, which is more than twice the caloric content of proteins and carbohydrates, both providing only 4 calories per gram.
Step-by-step explanation:
The macronutrient that has a caloric value of 9 calories per gram is fat. When comparing the caloric content of the macronutrients, we find that both proteins and carbohydrates provide about 4 calories per gram, while fats and oils, being more calorie-dense, provide approximately 9 calories per gram. Nutritional labels help consumers understand the caloric content of foods, indicating the amount of calories that come from each macronutrient. For instance, if a food label lists that a serving contains 12 grams of fat, this would equate to 12 g x 9 Calories/g = 108 calories just from fat.