What is a healthy diet?
Healthy diets contain the amounts of essential nutrients and
calories needed to prevent nutritional deficiencies and excesses. Healthy diets also
provide the right balance of carbohydrate, fat, and protein to reduce risks for chronic
diseases, and are a part of a full and productive lifestyle. Such diets are obtained from
a variety of foods that are available, affordable, and enjoyable.
The Dietary Guidelines describe food choices that promote
The Dietary Guidelines are designed to help
Americans choose diets that will meet nutrient requirements, promote health, support
active lives, and reduce chronic disease risks. Certain diets raise risks for chronic
diseases. Such diets are high in fat, saturated fat, cholesterol, and salt and they
contain more calories than the body uses. They are also low in grain products, vegetables,
fruit, and fiber.
Foods contain energy, nutrients, and other components that
People require energy and certain other essential
nutrients. These nutrients are essential because the body cannot make them and must obtain
them from food. Essential nutrients include vitamins, minerals, certain amino acids, and
certain fatty acids. Foods also contain other components such as fiber that are important
for health. Although each of these food components has a specific function in the body,
all of them together are required for overall health. People need calcium to build and
maintain strong bones, for example, but many other nutrients also are involved.
The carbohydrates, fats, and proteins in food supply
energy, is measured in calories. Carbohydrates and proteins provide about 4 calories per
gram. Fat contributes more than twice as much -- about 9 calories per gram. Alcohol,
although not a nutrient, also supplies energy -- about 7 calories per gram. Foods that are
high in fat are also high in calories. However, many lowfat or nonfat foods can also be
high in calories.