One reason i think protein is the most important nutrient to the body is because it helps build muscle mass and you need muscle for everything you do. My Second reason i think that is because proteins are essential for growth and maintenance of your body tissues. The Third reason is because proteins protect your body tissue and keep you healthy. The Fourth Reason is because protiens also produce energy as well as giving your body strength. The Last reason is that Protein can be used for energy when carbohydrate and fat are in short supply.