Nutrients are substances in food. We need nutrients to live and to grow. There are many food choices. If you go to the grocery store or a restaurant you can choose from many different foods. But, how do you know which ones are good for you and which ones are not? How do you know how much of each food you should eat? One easy way to figure this out is to folow the Food Guide Pyramid. Food Guide Pyramid is recommended by many doctors and is a simple way to eat healthy.