Your body works 24 hours a day. It's always building and repairing, feeding and cleansing itself. Its goal is to be ready for your every movement, breath, and thought. The quality of your life depends on how well your body works. And how well your body works depends on how much energy it gets. Energy comes from the food you eat. Food contains nutrients that your body needs for growth and energy. By eating a balanced diet, your body gets the six important nutrients it needs.Minerals  are nutrients that build bones and teeth. Minerals also form red blood cells and other substances.Wateraids digestion and waste removal.Carbohydrates  give your body its main source of energy. Two carbohydrates are sugars from foods such as fruits and vegetables and starches found in rice, potatoes, and bread.Fatshelp build cell membranes .Proteinsrepair and grow body tissues . Finally,vitaminshelp your body use carbohydrates, fats, and proteins. The United States Department of Agriculture(USDA) has created a nutritional food pyramid . It shows the daily number of servings you should eat from five food groups. The food pyramid has four levels. The base of the pyramid is the largest level. It contains the bread, cereal, rice, and pasta group from which you need six to eleven servings. The next level has two food groups: vegetables and fruits. The USDA recommends three to five servings of vegetables and two to four servings of fruit. The third level also has two groups: the milk, yogurt, and cheese group and the meat, poultry, fish, dry beans, eggs, and nuts group. You need two to three servings from each of these groups. The top of the pyramid is the smallest level. It contains fats, oils, and sweets. These foods have few nutrients, so eat them sparingly . To help the reader understand the six nutrients needed by the body, the author  _  .
describes the five basic food groups. explains what a balanced diet is. writes the details of each nutrient. tells the number of daily servings needed from each food group.