Part Four Your Health and Nutrition Selecting a healthful combination of foods requires a basic understanding of nutrients. Nutrients are the chemical substances in food that are used. by your body to keep it going. They are needed to promote growth and development, provide energy, and regulate body functions. Six types of nutrients are needed to nourish your body and keep it working properly. The six types of nutrients are proteins, carbohydrates, fats, vitamins, minerals, and water. No one food contains all the nutrients' needed for nourishing the body. You need to eat a variety of foods to get all the nutrients you need. Proteins 16=2 Exercise and eating right can help keep you healthy and allow you to do the activities you enjoy. will help you develop to the fullest possible extent. Good health as an adult will help you be successful in what ever you choose to do. You may have heard the expression "You are what you eat." This means eating a poor combination of foods could lead to poor health. Likewise, eating a healthful combination of foods will help keep you healthy. Your skin, hair, nails, muscles, blood, and all other body tissues contain protein. Proteins are needed for growth, maintenance, and repair of tissues. Proteins are also needed to control body processes, such as blood circulation, breathing, and digestion. Proteins act as a source of energy, too. Proteins are made of amino acids. Amino acids can be thought of as chains of blocks. They are used by your body to build the type of protein it needs. The body can make some amino acids. Others, called essential amino acids, cannot be made by the body. They must be obtained through foods. Meat, fish, poultry, cheese, eggs, milk, dry beans, peas, nuts, and seeds are all food sources of protein. Protein foods fall into two main groups. The protein from animal food sources is called complete protein. Complete protein supplies all the essential ammo acids your body needs, 16-3. The protein from plant food sources is called incomplete protein. Incomplete protein supplies only some of the essential amino acids. People who do not eat enough protein-rich foods may grow more slowly. They may also develop infections more easily and recover from illnesses at a slower rate. You can see why eating protein foods each day is important. R'esource: What Does the Body Need? transparency master 16-2, TR. nutrients that nourish the body and keep it working properly. Resource Discuss: What protein foods did you eat today? How can these help your body? i=nri,.,h Nutrients, Activity B, SAG. ~",*,a bulletin board illustrating various foods that contain
Chapter 16 Nutrition and You Carbohydrates Carbohydrates are nutrients that give your body its main source of energy for physical activities. If enough carbohydrates are not eaten to supply the energy you need, the body uses energy from proteins. This makes carbohydrates an important nutrient since proteins should be saved for the job of building and repairing tissµes. Three types of carbohydrates are sugars, starches, and fiber. Sugars can be used by your body as a quick source of energy. Starches take longer for your body to use as an energy source. Fiber does not supply your body with energy. Instead, it aids in digestion by helping push foods through the body at the proper speed. Candy, jelly, honey, milk, and frosting are food sources of sugars. Starches, along with sugars, are found in foods such as fruits, vegetables, breads, cereals, pasta, dry beans, and nuts. Fruits, vegetables, whole grains, and bran are food sources of fiber. The amount of carbohydrates needed each day depends on a person's activities. Eating more carbohydrates than you need could cause you to gain weight. This is because your body stores starch and sugar you do not need for energy as fat. If you do not eat enough carbohydrates, you may feel tired. You could also have digestive problems if you do not eat enough fiber. Remember that because your body needs energy, you need carbohydrates. Fats 16=g Foods from animals, such as this roast beef, are sources of complete proteins. They supply all of the essential amino acids your body needs. Enrich: Research the role of carbohydrates in the diets of athletes. Activity: Bring various magazine articles to class that promote various types of diets. Analyze these diets and determine whether or not they are nutritionally sound. Fats are concentrated sources of energy from animals or plants. They are needed to keep your body functioning efficiently. They carry some needed vitamins throughout your system. They insulate and protect vital organs' such as your heart, liver, and kidneys. Fat also forms a layer just under your skin that protects your body from cold temperatures.
Part Four Your Health and Nutrition You get fats from foods such as butter, margarine, meats, cheeses, salad dressings, and many snack and dessert foods, 16-4. Although you need to eat some fat, many people eat too much fat. This may cause weight gain or other health problems. Many experts agree that you should limit the amount of fat you eat. You can limit your intake of fat by choosing low-fat dairy products and lean meats (meats containing very little fat). Avoiding too many fried foods is another way you can limit the amount of fat you eat. Many high-fat foods are also high in cholesterol Cholesterol is a fatlike substance found in every human cell It is an essential part of blood and certain hormones. Cholesterol in the diet comes from animal food sources. Health authorities link too much cholesterol in the diet with heart disease. They recommend you limit dietary cholesterol to reduce your risk of health problems. Vitamins Vitamins are substances needed by the body for growth and maintenance. Vitamins help regulate the chemical processes in your body. They also help your body store and use energy for growth and development. Although required in very small amounts, vitamins are essential to life and health. You should try to eat foods that provide you with all the vitamins you need. Then you will not need to take vitamin pills to meet your daily requirements. Vitamins are either fat-soluble or watersoluble. Fat-soluble vitmnins are carried through your body by fats. The fat-soluble vitamins are vitamins A, D, E, and K. Fat-soluble vitamins can be stored by your body. Therefore, you do not need to eat food sources of them every day. In fact, getting more than the required amounts of these vitamins could be dangerous. This is because your body can store them in levels that could make you sick. If you eat foods containing these vitamins, there is no reason to take pills containing them in extra amounts. Water-soluble vitamins dissolve in water. This causes unused amounts of these vitamins to leave your body along with body wastes. Water-soluble vitamins cannot be stored in your body, so you need to eat foods that supply these vitamins every day. Vitamin C and the B vitamins are water-soluble. You should be aware of the main vitamins and what they do for your body. You also need to know what foods supply each of these vitamins. This knowledge will help you choose foods that make your body look and feel its best. Vitamin A 16=4 You need to be aware of fats in foods you eat, especially in snacks and desserts. Enrich: Research current information about dietary cholesterol and its link with heart disease. Discuss: Are vitamin supplements necessary if you eat a balanced diet? Vitamin A works to keep your skin in good condition. If your skin is dry and rough, you may need some of this important vitamin. Note: An orange coloring to the skin can result if you consume excess amounts of carotene.
Chapter 16 Nutrition and You In the Headlin~s "6-'d--' ":,.,..,,':;., ~:'f)y)f;;:_:j'::>,;;i;\;,;t' :>j;~:-:.;;;,:~<':: ;:;;-~'\;j!'i;i':'~-w,~s;'t::":~:.<r. t//~'.;)l;;;: :''2:.ti'd,(;:,;;<;-,:_:;''- _/j;;\~'i:7,,_~~:,c>,~r:s:~~,... Stud ie's:1nli icate'growi... ;"',',. Problem of Vitaimiri D~ficiencies Why aren't people getting enough vitamins in their diets? Do you think there are certain situations in which people should take vitamin ;i'< ;i;.':~:<;/:<-:'~: -_., Vitamin A is also necessary for normal vision. Without it, your eyes cannot adjust to bright light or darkness as well. Because vitamin A is fat-soluble, it can be stored by your body. However, you still need a good source of it at least every other day. Many deep yellow and dark green. vegetables and fruits are good sources of vitamin A. Such vegetable and fruit sources include carrots, broccoli, spinach, cantaloupe, peaches, and apricots, 16-5. These brightly colored vegetables and fruits contain a substance called carotene. This substance can be changed into vitamin A by your body. 16=5 Peaches are just one of many food sources of vitamin A. Vitamin A is also found in the fatty parts of animal products. Butter, cream, cheeses, egg yolks, and liver provide good sources of vitamina. The B Vitamins The B vitamins are a group of vitamins that work together in your body. Three key B vitamins are thiamin (vitamin B-1), riboflavin (vitamin B-2), and niacin (vitamin B-3). These vitamins help your body release energy from food. They promote growth, appetite, and digestion. They help keep your nervous system healthy and prevent irritability. They also keep skin healthy. The B vitamins are water-soluble so you need to include them in your diet every day. Luckily, getting daily sources of B vitamins is easy because they can be found in many foods. Foods rich in B vitamins include whole - grains and enriched breads and cereals. Leafy green vegetables, legumes, meat, milk, and eggs are also good sources. Vitamin C Vitamin C helps produce a substance that holds body cells together. Through this function, vitamin C plays an important role in your body. It helps broken bones mend and wounds heal It strengthens the walls of blood vessels. Vitamin C also helps your body use some other nutrients. It helps you resist infections and maintain healthy gums, skin, and teeth. Vitamin C is water-soluble and is not stored in the body. Therefore, you need at least one good source of vitamin C each day to keep this vitamin in your body.' Vitamin C is found in many fruits and vegetables. Citrus fruits, such as oranges and grapefruit, are great sources. Cantaloupe, strawberries, broccoli, and tomatoes are also good sources of this vitamin. Vitamin D Vitamin D helps your body use the minerals that are needed to build bones and teeth. This function is especially important during periods Enrich: Folic acid is an additional B vitamin. Research current information about this vitamin in relation to its role in preventing birth defects. Discuss: What are your favorite sources of vitamin C? Discuss: What is a nonfood source of viiamin D?
Part Four Your Health and Nutrition when your body is growing rapidly. Periods of rapid growth occur during childhood and adolescence. Vitamin D is sometimes called "the sunshine vitamin." This is because your body can make vitamin D when exposed to sunlight. Besides the sun, another source of vitamin D is fortified milk, 16-6. Fortified means nutrients have been added to the food product. Fish liver oil and some fish are other good sources of vitamin D.. Vitamin E Vitamin E is believed to keep oxygen in the body from destroying other nutrients, especially vitamin A. So many foods contain vitamin E that people rarely suffer from deficiencies, or shortages. Some important sources are vegetable oils, whole grain breads and cereals, eggs, organ meats, and leafy green vegetables. Vitamin K Vitamin K helps blood clot. As with vitamin E, many foods contain vitamin K so deficiencies are rare. Some important sources are green leafy vegetables, cauliflower, liver, and egg yolk. Minerals _ Minerals are another type of nutrient needed for a healthy body. Minerals help regulate many of your body's activities. They help muscles contract and nerves transmit signals to and from the brain. They also help maintain the body's water balance and strengthen bones and teeth. Although there are many minerals known to be needed, the most well known are calcium, phosphorus, chlorine, potassium, and sodium. Also included are the trace minerals iron,. iodine, and fluorine. Trace minerals are' minerals that are found in only small amounts in the body. Calcium and Phosphorus Calcium and phosphorus are two minerals that work together as a team. Both are more effective when the other is present. They are both needed for strong bones and teeth. They are also important for clotting of blood and for normal heart and muscle formation. The richest food sources of calcium are milk and milk products, including yogurt and hard cheeses. Other good sources are fish and green, leafy vegetables. Foods that are rich in calcium are also good sources of phosphorus. 16-6 Milk is often fortified to provide you with vitamin D. Resource: Nutrient Sources, transparency master 16-2, TR. Vocabulary: What does clotting mean in relation to blood? Activity: Make a chmt listing minerals and their sources. Reflect: How many sources of calcium and phosphorus did you eat today?
Chapter 16 Nutrition and You Sodium, Chlorine, and Potassium Sodium, chlorine, and potassium work together in your body. They help keep the right amount of fluid around and inside the cells in your body. They allow the cells to take up nutrients from the blood. These minerals also help nerves and muscles function as they should. These minerals are found in many foods. Table salt is a source of sodium and chlorine. Potassium is plentiful in bananas, orange juice, green leafy vegetables, and milk. Many people eat more sodium than they need for good nutrition. Excess sodium is usually removed from the body as waste. However, some people have a problem with sodium staying in the body. Sodium has been linked to high blood pressure. For patients with this health problem, doctors may prescribe a low-sodium diet. Many foods are available that would conform with this type of diet. These foods have been processed with little or no salt and may be labeled as "low-sodium" or "salt-free." Iron Iron is important for healthy red blood cells. Lack of iron may cause anemia. A person who has anemia may feel tired, lack energy, and sense a loss of appetite. Eating enough foods that contain iron is especially important for females because they lose iron during monthly menstrual periods. Liver is an excellent source of iron. Other sources are meat, fish, eggs, dried beans and peas, and whole grain or enriched breads and cereals. Iodine Iodine is used to help the thyroid gland produce a hormone that affects growth and weight. If your body does not receive enough iodine, the thyroid will get larger in trying to produce this hormone. This condition is seen as a swelling at the front of the throat and is called goiter. Iodine is added to iodized salt, 16-7.Most people use enough salt to meet their needs for this mineral. Saltwater fish are also a good source of iodine. Fluorine Fluorine is needed for the proper development of teeth and bones. Scientists have found that fluorine is useful in the prevention of tooth decay. Therefore, it is added to many brands of toothpaste. Many cities add fluorine to their drinking water supplies. Small amounts are also found in meats, milk, and eggs. Water Water is the single most important substance you take into your body. You can get along for days, even weeks, without food. You can only survive a few days without water, 16-8. About two-thirds of your body is made up of water. Water carries nutrients into cells and carries wastes out of the body. The food you eat cannot be digested and used by the body without an adequate supply of water. Water also helps regulate the internal temperature of your body. 16~7Iodized salt is the most common source of the trace mineral iodine. Enrich: Research current studies about sodium and its link to high blood pressure. Discuss: What are good sources of iron that vegetarians may want to include in their diets? Discuss: Why is salt often iodized? Enrich: Find out whether your source of drinking water is fluoridated.