Nutrients are life-sustaining chemical substances that nourish and promote the growth of the human body. No one food contains all of the nutrients necessary for the body to function effectively; therefore, a balanced diet that incorporates appropriate amounts of the six essential nutrients, as well as recommended servings from the food groups, is necessary. Individuals should choose foods of high nutrient density rather than foods with empty calories. Foods that are nutrient dense are foods that are excellent sources of essential nutrients with few, if any, empty calories. Empty calorie foods refer to foods that provide calories or energy but little or no nutritive value. The six essential nutrients are protein, carbohydrates, vitamins, minerals, fats, and water.