Which of the following nutrients is not typically a source of energy?

Vitamins are classified as micronutrients, which means they are required in smaller amounts compared to macronutrients like carbohydrates, proteins, and fats. Unlike these macronutrients, vitamins do not provide energy (calories) to the body. Instead, their primary role is to facilitate various biochemical processes that are essential for maintaining health, such as acting as coenzymes in metabolic pathways.

Carbohydrates, proteins, and fats are macronutrients, and they all serve as sources of energy. Carbohydrates are often the body's preferred source of energy, while fats provide a concentrated source of energy, and proteins can also be used for energy in certain situations, such as during prolonged exercise or when carbohydrate intake is insufficient. However, it is the vitamins that do not directly provide energy, highlighting their important but different role in nutrition compared to macronutrients.