Chapter 14 A Healthy Diet

Nutrients for the Body Scientists have identified nutrients that body needs. Nutrients are food substances required for the growth and maintenance of your cells. They are divided into six groups: carbohydrates, proteins, fats, vitamins, minerals, and water.

Nutrients that provide energy Three types of nutrients supply the energy your body needs: Carbohydrates Proteins Fats

Carbohydrates They are your bodies main source of energy There are two kinds: Simple and Complex Complex are sugars found in foods such as whole-grain breads, vegetables, and grain. Simple should account for 15 percent or less of the total calories in your diet. Contains sugars from fruit juices, candy, pastries, and soft drinks. Fiber is a type of complex carbohydrate that your body cannot digest.

Protein Proteins are the group of nutrients that builds, repairs and maintains body cells. They are the building blocks of your body. Animal products such as milk, eggs, meat, and fish, contain proteins. Some plants such as beans and grains may also contain protein. Provide energy but not as much as carbohydrates or fats. Amino acids are simpler substances your body breaks protein down to. Complete proteins contain all nine essential amino acids. Incomplete proteins contain some, but not all of them.

Fats Are in animal products and some plant products such as nuts or vegetable oils. Saturated fats are solid at room temperature. Usually from meat. Unsaturated fats are liquid at room temperature. Usually from plants.

Minerals Essential nutrients that help regulate the activities of cells. Come from earth’s crust. Present in plants and animals. We need 25 different minerals in varying amounts. Eating a variety of foods will help provide adequate amounts.

Functions and Sources of Minerals MineralFunctions in the bodyFood Sources Calcium Builds and maintains teeth and bones; helps blood clot; helps nerves and muscles function Cheese; milk; dark green vegetables; sardines; legumes Phosphorus Builds and maintains teeth and bones; helps release energy from nutrients Meat; poultry; fish; eggs; legumes; milk products Magnesium Aids breakdown of glucose and proteins; regulates body fluids Green vegetables; grains; nuts; beans; yeast Sodium Regulates internal water balance; helps nerves function Most foods; table salt Potassium Regulates fluid balance in cells; helps nerves function Oranges; bananas; meats; bran; potatoes; dried beans Iron Helps transfer oxygen in red blood cells and in other cells Liver; red meats; dark green vegetables; shellfish; whole-grain cereals Zinc Aids in transport of carbon dioxide; aids in healing wounds Meats; shellfish; whole grains; milk; legumes

Vitamins Needed for growth and repair of body cells. Vitamin C and B vitamins are water soluble. Vitamin A, D, E, and K are fat soluble and dissolve in fat.

Water Carries other nutrients to cells, carries away waste, and helps regulate body temperature. Most of our body weight is made up of water. 50 to 60 percent How much water is enough?

The Food Pyramid Fats, Oils and Sweets-Use Sparingly Dairy: 2-3 servings Meats, nuts and legumes: 2-3 servings Vegetables: 3-5 servings Fruits: 2-3 servings Bread, Grain and Pasta: 6-11 servings

Food Choices What is important to know on a food label? What do food labels claim?

Myths Skipping meals is a good way to lose weight. A food supplement is tested for safety and to insure that it meets claims advertised by the seller. High protein diets are best for losing weight and maintaining good health. If you limit the amount of fat in foods, you do not need to be concerned with how many calories a food contains.

Eating Before Physical Activity Special diets are typically not necessary before athletic competitions. Allow extra time between eating and activity before vigorous competitive events. Before competition, reduce the size of your meal. Drink fluids before, during, and after activity.