The macronutrients are carbohydrates, fats, protein, and water. The macronutrients (excluding fiber and water) provide structural material (amino acids from which proteins are built, and lipids from which cell membranes and some signaling molecules are built) and energy. Some of the structural material can be used to generate energy internally, and in either case it is measured in Joules or kilocalories (often called "Calories" and written with a capital C to distinguish them from little 'c' calories). Carbohydrates and proteins provide 17 kJ approximately (4 kcal) of energy per gram, while fats provide 37 kJ (9 kcal) per gram, though the net energy from either depends on such factors as absorption and digestive effort, which vary substantially from instance to instance. Vitamins, minerals, fiber, and water do not provide energy, but are required for other reasons. COUNT 5
QSN1 Which category is represented by carbohydrates and fats among other nutrients? ANS1 macronutrients QSN2 What other significant aspect do macronutrients provide other than energy? ANS2 structural material QSN3 What unit other than calories is used to measure the energy generated by nutrients? ANS3 Joules QSN4 Which nutrient generally provides around 37 kJ per gram? ANS4 fats QSN5 Although vitamins are important for many reasons, which role do they not play in the human body? ANS5 provide energy