LESSON 25 Choosing Healthful Foods Before You Read List some of the healthful foods you eat. What makes these foods healthful choices? What You ll Learn the functions and sources of proteins, carbohydrates, fats, vitamins, minerals, water, and herbal supplements the five required elements and other information on food labels Read to Learn Proteins Healthful foods contain nutrients your body needs. A nutrient is a substance found in food that helps with body processes. The foods you eat give you energy. Energy is measured in calories. A calorie is a unit of energy produced by food and used by the body. Different nutrients provide different things your body needs. A nutrient that is needed for growth, to build, repair, and maintain body tissues, to regulate body processes, and to supply energy is a protein. Proteins form part of every cell in your body. They help your body maintain strength and resist infection. A diet that does not supply enough protein might stunt your growth, affect the development of certain tissue, and affect mental health. There are two kinds of proteins: complete proteins and incomplete proteins. Complete proteins A protein that contains all of the essential amino acids is a complete protein. Amino acids are the building blocks of proteins. Examples of foods that contain complete proteins are meat, fish, poultry, milk, yogurt, and eggs. Your body needs 20 amino acids to function properly. Your body can produce only 11 of these amino acids. The nine amino acids your body cannot produce are called essential amino acids. The nine essential amino acids must come from food. Soy beans are the only plant food that provides all nine essential amino acids. As you read this lesson, organize information about healthful foods in a table. In the first column, list categories of items, such as the categories of nutrients. Use the space in the other columns to describe details about each category, such as why your body needs the nutrients and foods that are sources of the nutrient. Use your notes to help you review the lesson. 1. What are three examples of foods that contain complete proteins? Reading Essentials LESSON 25 189
2. Describe a meal which contains grains (whole grains, pasta, corn), legumes (dried beans, peas, and lentils), and nuts and seeds. 3. Why is fiber an important part of a healthful diet? Incomplete proteins Proteins from plant sources that do not contain all the essential amino acids are incomplete proteins. Incomplete proteins from plant sources fall into three main categories: grains, legumes, and nuts and seeds. These can be combined to obtain all of the essential amino acids you need. Carbohydrates A nutrient that is the main source of energy for the body is a carbohydrate. Carbohydrates include sugars, starches, and fiber. There are two types of carbohydrates: simple and complex. Simple carbohydrates Sugars that enter the bloodstream and provide quick energy are simple carbohydrates. They provide calories but few vitamins and minerals. Sugars are found naturally in fruits, honey, and milk. Processed sugar, or table sugar, is added to food during processing. Cakes, candy, ketchup, and soda pop contain processed sugar. Complex carbohydrates Starches and fiber are complex carbohydrates. Most calories in your diet should come from complex carbohydrates. Starches include bread, pasta, potatoes, and beans. These foods provide longer-lasting energy. Fiber The part of grains and plant foods that cannot be digested is fiber. Fiber helps move food through the digestive system. Good sources of fiber include grains, breads and cereals, seeds, dried beans, fruits, and vegetables. There are two types of fiber: soluble and insoluble. Insoluble fiber helps prevent intestinal problems by binding with water. It also is linked to a reduced risk of colon cancer. Soluble fiber reduces blood cholesterol and the risk of heart disease. 4. A friend tells you he has heard that cutting carbohydrates from his diet will help him lose weight. How might you respond to your friend? 190 LESSON 25 Reading Essentials
Fats A nutrient that provides energy and helps the body store and use some vitamins is a fat. The body needs fats to maintain body heat, maintain an energy reserve, and build brain cells and nerve tissues. 5. How does your body use fats? Saturated fats Fats found in dairy products, meat, and poultry are saturated fats. Saturated fats are usually solid at room temperature. Saturated fats contribute to the level of cholesterol that is in a person s blood. Unsaturated fats Fats from plant products and fish are unsaturated fats. Unsaturated fats are usually liquid at room temperature. Examples of unsaturated fats include sunflower, corn, olive, and canola oils. Trans-fatty acids When vegetable oils are processed into solid fats, such as margarine, trans-fatty acids are formed. Trans-fatty acids are found in vegetable shortening, some margarines, crackers, cookies, donuts, snack foods, and other foods. Trans-fatty acids appear to raise blood cholesterol levels. You can identify foods that contain trans fat by looking on labels for partially hydrogenated vegetable oil or vegetable shortening. 6. List fats you have eaten today. Which fats were saturated? Which were unsaturated? Vitamins A nutrient that helps the body use carbohydrates, proteins, and fats is a vitamin. Vitamins do not provide energy to the body directly, but they help free energy stored in carbohydrates, proteins, and fats. There are two different types of vitamins fat-soluble vitamins and water-soluble vitamins: Fat-soluble vitamins A vitamin that dissolves in fat and can be stored in the body is a fat-soluble vitamin. The fat-soluble vitamins are vitamins A, D, E, and K. Water-soluble vitamins A vitamin that dissolves in water and cannot be stored in the body is a watersoluble vitamin. Water-soluble vitamins include vitamin C and B complex vitamins. Reading Essentials LESSON 25 191
7. What vitamin is necessary for normal blood clotting? 8. Read about vitamins in the table. Fill in the column beside each vitamin with a food you have eaten in the past week in which the vitamin is found. Try not to repeat the names of foods. Name of Vitamin Function and Foods in Which It Is Found Examples Vitamin A Vitamins Keeps eyes, hair, and skin healthy; found in dairy products, fruits, and green and yellow vegetables. Vitamin D Aids in formation of bones and teeth; found in meat and dairy products. Vitamin E Helps form and maintain cells; found in green vegetables and whole-grain cereals. Vitamin K Necessary for normal blood clotting; found in leafy, green vegetables and cheese. Vitamin C Strengthens blood vessel walls and immune system; found in citrus fruits and leafy, green vegetables. Vitamin B 1 (Thiamin) Necessary for the function of nerves; found in whole grains, poultry, and eggs. Vitamin B 2 (Riboflavin) Vitamin B 3 (Niacin) Vitamin B 6 Vitamin B 9 (Folacin) Vitamin B 12 Biotin Helps body use energy; found in milk, eggs, whole grain, and leafy, green vegetables. Aids in function of body systems, helps body use energy; found in yeast, wheat germ, fish, and dairy products. Helps your body use fat and take in protein; found in whole grains and leafy, green vegetables. Necessary for forming hemoglobin in red blood cells; found in green vegetables, liver, and whole grains. Necessary for the formation of red blood cells; found in meat and dairy products. Necessary for metabolism of carbohydrates; found in green vegetables, bananas, and peanuts. Pantothenic acid Necessary for production of RNA and DNA; found in milk, whole grains, and green vegetables. 192 LESSON 25 Reading Essentials
Minerals A nutrient that regulates many chemical reactions in the body is a mineral. There are two types of minerals: macro minerals and trace minerals. Macro minerals Minerals that your body requires in amounts greater than 100 milligrams are called macro minerals. Examples of macro minerals are calcium, magnesium, phosphorus, potassium, sodium, and sulfur. Calcium helps build bones and teeth. Milk, cheese, legumes, soybean products, and leafy, green vegetables all contain calcium. Magnesium is necessary for chemical reactions during metabolism. Good sources of magnesium are soybean products, whole grains, beans, nuts, seeds, fruit, and leafy, green vegetables. Phosphorus builds bones, teeth, and cells. Phosphorus is found in milk, meat, poultry, legumes, and cheese. Potassium keeps fluids balanced within cells. Potassium can be found in green vegetables, legumes, and fruit. Sodium is necessary for water balance in cells and tissues and functioning of nerve cells. Sodium is found in table salt, cheese, and crackers. Sulfur builds hair, nails, and skin. Sources of sulfur are meats, milk, eggs, legumes, nuts, cheese, and brown sugar. Trace minerals Minerals that your body needs in very small amounts are trace minerals. Examples of trace minerals are copper, iodine, iron, manganese, and zinc. Copper is necessary for the production of hemoglobin in red blood cells. Copper can be found in red meat, liver, seafood, poultry, legumes, and nuts. Iodine is necessary for production of the thyroid gland hormone. Sources of iodine are iodized salt, milk, cheese, fish, and whole grains. 9. Suppose you want to find out about other macro and trace minerals important to your health. Where might you look for reliable information? 10. Name two macro minerals your body needs. Reading Essentials LESSON 25 193
11. Where are herbal supplements sold? 12. Why should you be particularly cautious about using herbal or protein supplements? Iron helps red blood cells transport oxygen. Liver, red meat, fish, eggs, legumes, and whole grains contain iron. Manganese helps make cholesterol and helps nerves function. Manganese can be found in whole grains, leafy, green vegetables, fruits, legumes, and nuts. Zinc is necessary for digestive enzymes and for healing wounds. Seafood, milk, eggs, red meats, poultry, and whole grains contain zinc. Herbal Supplements Supplements that contain extracts or ingredients from the roots, berries, seeds, stems, leaves, buds, or flowers of plants are herbal supplements. Herbal supplements are classified as foods and not as drugs. This means they do not have to be proven safe or screened by the Food and Drug Administration before they are sold. Herbal supplements are sold in health food stores, grocery stores, gyms, and through mailorder catalogs and the Internet. A product taken orally that contains proteins that are intended to supplement one s diet and are not considered food are protein supplements. Many people who consume protein supplements believe that the extra protein helps them build muscle. Most people meet or exceed the recommended daily amount of protein without the use of supplements. Extra protein in the body is stored as fat and not muscle. Before you take any supplement, you should ask yourself questions such as: Do I know what ingredients are in the supplement? Have I talked with my physician about the risks and benefits of taking this supplement? Do I know that this supplement is safe and that it does what it claims to do? Does the product make claims that seem too good to be true? Do I know if this supplement can interact with the foods I eat and the drugs that I am taking? 194 LESSON 25 Reading Essentials
Water Water is a nutrient that is involved in all body processes. Water makes up part of the blood, helps with waste removal, regulates body temperature, and cushions the spinal cord and joints. Your body is more than 60 percent water. You can live without other nutrients for months, but you can survive without water only for about three days. A condition in which the water content of the body has fallen to an extremely low level is dehydration. Dehydration can be caused by not drinking enough water, fever, vomiting, or diarrhea. To prevent dehydration, drink plenty of water, especially during hot weather, when you exercise, or when you are sick. Soda pop and other drinks that contain caffeine are not good substitutes for water. Drinks with caffeine cause more frequent urination. 15. How can drinking caffeinated drinks lead to dehydration? 13. How can you keep yourself from becoming dehydrated? 14. When reading a nutrition label, what does the listing called Percent Daily Value tell you? What is the Percent Daily Value of vitamin C on the label below? Food Labels A food label is a panel of nutrition information required on all processed foods regulated by the Food and Drug Administration (FDA). Nutrition Information Required on All Food Labels name of the food net weight or volume name and address of manufacturer, distributor, or packager ingredients nutrient content serving size (the amount of food considered a serving). Servings are determined by the FDA, not the product manufacturer. number of calories in one serving calories from fat in one serving portion of the daily amount of nutrients provided by one serving. This is called the Percent Daily Value. This percentage is based on a diet of 2,000 calories. serving per container Nutrition Facts Serving Size 1/2 cup (114g) Servings Per Container 4 Amount Per Serving Calories 90 Calories from Fat 30 % Daily Value* Total Fat 3g 5% Saturated Fat 0g 0% Cholesterol 0mg 0% Sodium 300mg 13% Total Carbohydrate 13g 4% Dietary Fiber 3g 12% Sugars 3g Protein 3g Vitamin A 80% Vitamin C 60% Calcium 4% Iron 4% *Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs: Calories: 2,000 2,500 Total Fat Less than 65g 80g Sat Fat Less than 20g 25g Cholesterol Less than 300mg 300mg Sodium Less than 2,400mg 2,400mg Total Carbohydrate 300g 375g Dietary Fiber 25g 30g Calories per gram: Fat 9 Carbohydrate 4 Protein 4 Reading Essentials LESSON 25 195
The servings per container is the listing of the number of servings in the container or package. You should read this number carefully. Suppose you drink a bottle of juice that lists the number 90 next to the category calories. You might think you have consumed 90 calories. However, if the bottle contains two servings, you actually are consuming 180 calories. Multiply the calories and nutrient amounts by the number of servings per container to determine the total number of calories and nutrient amounts in a container or package. 16. How do you know which ingredients are present in the greatest amount in a food? 17. Why do you think it is important to have nutritional guidelines for foods that make claims such as fat free or sugar free? Decoding Food Labels Along with nutrition facts, other information can be found on a food label. This information might be found on the nutrition facts panel, or it might be found elsewhere on the packaging. This information includes a listing of ingredients, food additives, and other important facts. The food label is not required on fresh fruits and vegetables, food served in restaurants, foods sold by vendors, bakery and deli products, and coffee or tea. Almost all foods must have an ingredients listing. Ingredients are listed by weight, beginning with the ingredient that is present in the greatest amount. Information involving dates might be included on the food label. Sell By is the last date that the product should be sold. Best If Used By is the date by which the product should be used to ensure quality. Expiration Date is the date after which the product should not be used. Food health claims A food product that claims the food to be healthy must be low in fat, low in saturated fat, and have no more than 60 mg of cholesterol per serving. Any product that claims to be fat, sodium, cholesterol, sugar, or caffeine free must follow guidelines that the product has no or only a very small amount of fat, sodium, cholesterol, sugar, or caffeine. A product that claims to be fresh must be raw, unprocessed, contain no preservatives, or never have been frozen or heated. 196 LESSON 25 Reading Essentials
Food additives must also be listed on food labels. Food additives might add nutrients, flavor, color, or texture. They also might help prevent the food from spoiling. Foods might be enriched or fortified to add to the nutrient value. An enriched food is a food in which nutrients lost during processing are added back into the food. A fortified food is a food in which nutrients not usually found in the food are added. 18. What is the difference between an enriched food and a fortified food? 19. Read the questions in the table below that you should ask yourself when comparing food labels. Fill in the column beside each question with a real-life example of how this question can influence your health status. Comparing Food Labels Questions to Ask Yourself Examples What people and things might influence my choice? What is the saturated fat content of the food? What are the Percent Daily Values for dietary fiber and sugar? What are the total calories per serving of the food? Reading Essentials LESSON 25 197
After You Read Reviewing Key Terms amino acids: the building blocks of proteins calorie: a unit of energy produced by food and used by the body carbohydrate: a nutrient that is the main source of energy for the body fiber: the part of grains and plant foods that cannot be digested herbal supplements: supplements that contain extracts or ingredients from the roots, berries, seeds, stems, leaves, buds, or flowers of plants mineral: a nutrient that regulates many chemical reactions in the body nutrient: a substance found in food that helps with body processes protein: a nutrient that is needed for growth, to build, repair, and maintain body tissues, to regulate body processes, and to supply energy protein supplements: a product taken orally that contains proteins that are intended to supplement one s diet and are not considered food vitamin: a nutrient that helps the body use carbohydrates, proteins, and fats Review the definitions of the Key Terms. Then write a sentence for each of the following terms: calorie, herbal supplements, and vitamin. Reviewing the Main Ideas Use the spider map to write two details that describe each nutrient. Protein Vitamin Carbohydrate Fat Nutrients Mineral Water Suppose you have a choice between two brands of granola bars. How can you compare food labels to make the most healthful choice? 198 LESSON 25 Reading Essentials