Protein is one of the essential macronutrients in a diet, along with carbohydrates and fats. But protein is much more than that. Protein is the most versatile of all macronutrients as it is crucial for many biological processes such as transporting oxygen throughout the body, supporting the immune system, transmitting nerve impulses, controlling growth and development of cells and tissues, and more. You may have heard of amino acids. These are the building blocks of proteins, some which your body can make on its own and some which you must get from food. “Essential” amino acids are those that your body cannot produce, therefore they must be supplied through protein in foods.