Chapter 2 Nutritional Needs

2. Chapter 2Nutritional Needs Part 1 The Importance of Food Note: This chapter covers the functions and sources of key nutrients; the effects of various nutrient deficiencies and excesses; and the processes of digestion, absorption, and metabolism. This presentation displays the text objective related to each of these topics, followed by information to help students achieve the objective.Note: This chapter covers the functions and sources of key nutrients; the effects of various nutrient deficiencies and excesses; and the processes of digestion, absorption, and metabolism. This presentation displays the text objective related to each of these topics, followed by information to help students achieve the objective.

3. Objective Name the key nutrients, describe their functions, and list important sources of each. Discuss: What nutrients can you name? Why is it important to be aware of what nutrients do in your body and what foods provide them?Discuss: What nutrients can you name? Why is it important to be aware of what nutrients do in your body and what foods provide them?

4. The Nutrients A nutrient is a chemical substance that helps maintain the body. You need over 50 nutrients, which can be divided into six groups. Carbohydrates Fats Proteins Vitamins Minerals Water Discuss: What have you heard about the health effects of any of these nutrient groups?Discuss: What have you heard about the health effects of any of these nutrient groups?

5. Key Nutrient: Carbohydrates Functions Supply energy Provide bulk Help the body digest fats Spare proteins Discuss: Why do you need bulk in your diet? What is the value of sparing proteins?Discuss: Why do you need bulk in your diet? What is the value of sparing proteins?

6. Sources of Carbohydrates Sugars�honey, jam Fiber sources�fruits, vegetables, whole grains Starch sources�breads, cereals, pasta What is your favorite source of carbohydrates? Discuss: What do the terms simple carbohydrates and complex carbohydrates mean? Which type of carbohydrates should provide most of the calories in your diet?Discuss: What do the terms simple carbohydrates and complex carbohydrates mean? Which type of carbohydrates should provide most of the calories in your diet?

7. Key Nutrient: Fats Functions Supply energy Carry fat-soluble vitamins Insulate the body Protect organs Provide essential fatty acids Discuss: What functions do fats serve in foods?Discuss: What functions do fats serve in foods?

8. Saturated�dairy products, meats Mono- and Polyunsaturated�fish, nuts, vegetable oils Sources of Fats Discuss: How do fats that are high in saturated fatty acids differ from those that are high in unsaturated fatty acids? How can you reduce the amount of saturated fats from dairy products and meats in your diet? What are some other food sources of mono- and polyunsaturated fats?Discuss: How do fats that are high in saturated fatty acids differ from those that are high in unsaturated fatty acids? How can you reduce the amount of saturated fats from dairy products and meats in your diet? What are some other food sources of mono- and polyunsaturated fats?

9. Functions Build and repair tissues Help body make important substances Regulate body processes Supply energy Key Nutrient: Proteins Discuss: Which of these functions is also performed by other nutrients?Discuss: Which of these functions is also performed by other nutrients?

10. Sources of Proteins Complete proteins�dairy products, eggs, fish, meat, poultry Incomplete proteins�beans, grains, nuts How can you find out if a food is a good source of protein? Discuss: Why are some sources of proteins considered to be �complete� while others are considered to be �incomplete�? What can you do to improve the nutritional value of incomplete sources of protein?Discuss: Why are some sources of proteins considered to be �complete� while others are considered to be �incomplete�? What can you do to improve the nutritional value of incomplete sources of protein?

11. Key Nutrient: Vitamins Vitamins can be divided into two main groups. Fat-soluble vitamins dissolve in fats can be stored in fatty tissues of the body Water-soluble vitamins dissolve in water are not stored in the body Note: Each vitamin performs different specific functions. In general, vitamins support normal growth, maintenance of body tissues, and reproduction. Each vitamin is also found in different food sources. Eating a variety of foods is the best way to get all the vitamins you need. Note: Each vitamin performs different specific functions. In general, vitamins support normal growth, maintenance of body tissues, and reproduction. Each vitamin is also found in different food sources. Eating a variety of foods is the best way to get all the vitamins you need.

12. Fat-Soluble Vitamins Note: Due to space limitations, not all functions and sources are listed. See Table 2-9 in the text for more detail. Discuss: What advantages and disadvantages are created by the body�s ability to store fat-soluble vitamins in the fatty tissues?Note: Due to space limitations, not all functions and sources are listed. See Table 2-9 in the text for more detail. Discuss: What advantages and disadvantages are created by the body�s ability to store fat-soluble vitamins in the fatty tissues?

13. Water-Soluble Vitamins Note: Due to space limitations, not all functions and sources are listed. See Table 2-13 in the text for more detail. Other B-complex vitamins include vitamin B6, vitamin B12, pantothenic acid, and biotin. Discuss: What other nutrients are provided by the food sources of each of these vitamins? Note: Due to space limitations, not all functions and sources are listed. See Table 2-13 in the text for more detail. Other B-complex vitamins include vitamin B6, vitamin B12, pantothenic acid, and biotin. Discuss: What other nutrients are provided by the food sources of each of these vitamins?

14. Key Nutrient: Minerals Minerals can be divided into two main groups. Macrominerals are needed in amounts of 100 mg or more per day. Trace elements are needed in amounts less than 100 mg per day. Note: Each mineral performs different specific functions. In general, minerals become part of the bones, soft tissues, and body fluids and help regulate body processes. Each mineral is also found in different food sources. Eating a variety of foods is the best way to get all the minerals you need. Discuss: What is another name for trace elements? Note: Each mineral performs different specific functions. In general, minerals become part of the bones, soft tissues, and body fluids and help regulate body processes. Each mineral is also found in different food sources. Eating a variety of foods is the best way to get all the minerals you need. Discuss: What is another name for trace elements?

15. Macrominerals Note: Due to space limitations, not all functions and sources are listed. See Table 2-16 in the text for more detail. Discuss: Why is it especially important for teens to get adequate sources of calcium in their daily diets? What is the largest source of sodium and chloride in the U.S. diet?Note: Due to space limitations, not all functions and sources are listed. See Table 2-16 in the text for more detail. Discuss: Why is it especially important for teens to get adequate sources of calcium in their daily diets? What is the largest source of sodium and chloride in the U.S. diet?

16. Trace Elements Note: Due to space limitations, not all functions and sources are listed. See Table 2-18 in the text for more detail. Other trace elements include copper, selenium, and manganese. Discuss: Because they are needed in smaller amounts, do you think trace elements are less important for good health than macrominerals? Explain why or why not.Note: Due to space limitations, not all functions and sources are listed. See Table 2-18 in the text for more detail. Other trace elements include copper, selenium, and manganese. Discuss: Because they are needed in smaller amounts, do you think trace elements are less important for good health than macrominerals? Explain why or why not.

17. Key Nutrient: Water Functions Aids digestion and cell growth and maintenance Facilitates chemical reactions Lubricates joints and cells Regulates body temperature Discuss: What factors would increase a person�s need for water?Discuss: What factors would increase a person�s need for water?

18. Sources of Water Liquids Food Breakdown of energy nutrients Which source do you think provides most of your water needs? Discuss: What types of foods would have high water content?Discuss: What types of foods would have high water content?

19. Objective Analyze the effects of various nutrient deficiencies and excesses. Discuss: Why is it important to consume the right balance of the various nutrients?Discuss: Why is it important to consume the right balance of the various nutrients?

20. Nutrient Deficiencies Failure to get a sufficient amount of a nutrient may result in an illness called a deficiency disease. Such diseases include protein-energy malnutrition (protein) night blindness (vitamin A) rickets (vitamin D) scurvy (vitamin C) osteoporosis (calcium) Discuss: What other nutrient deficiency diseases can you name?Discuss: What other nutrient deficiency diseases can you name?

21. Nutrient Excesses Excess energy nutrients�carbohydrates, fats, and proteins�can lead to unhealthful weight gain. Excesses of some vitamins and minerals can lead to toxicity (poisoning) and other complications. Discuss: If nutrients are good for you, why wouldn�t consuming more of them always be better for you? Discuss: If nutrients are good for you, why wouldn�t consuming more of them always be better for you?

22. Apply It! Your grandmother has been diagnosed with osteoporosis. What is the likely cause of this affliction? What health effects may your grandmother suffer as a result of this disease? Discuss: What steps can you take now to avoid developing osteoporosis as you age?Discuss: What steps can you take now to avoid developing osteoporosis as you age?

23. Objective Explain the processes of digestion, absorption, and metabolism. Discuss: What can you do to help your body digest foods and use the nutrients they provide?Discuss: What can you do to help your body digest foods and use the nutrients they provide?

24. The Digestion Process Digestion is the bodily process of breaking food down into simpler compounds the body can use. The mechanical phase involves the physical breakdown of food caused by chewing and muscle activity in the digestive tract. The chemical phase involves the chemical breakdown of food caused by enzymes in saliva and digestive juices. Discuss: What parts of your body are involved in the digestion process?Discuss: What parts of your body are involved in the digestion process?

25. The Absorption Process Absorption is the process of taking in nutrients and making them part of the body. A large surface area in the small intestine allows tiny nutrient particles to pass into the blood and lymph systems and travel where needed. What would happen if your body were unable to absorb the nutrients you consumed through foods? Discuss: How must carbohydrates, fats, and proteins be broken down before the body can absorb them? Discuss: How must carbohydrates, fats, and proteins be broken down before the body can absorb them?

26. Metabolism Metabolism is the chemical processes that take place in the cells after the body absorbs nutrients. Carbohydrates are converted into glucose for use as an energy source. Fatty acid chains from fats are shortened and fats are used for fuel. Amino acids from proteins are used for maintenance, growth, production of enzymes and antibodies, and energy. Discuss: What roles do vitamins, minerals, and water play in metabolism?Discuss: What roles do vitamins, minerals, and water play in metabolism?

27. Key Question What are your nutritional needs? Note: Encourage students to use this question to help them review chapter information and apply it to their lives. Note: Encourage students to use this question to help them review chapter information and apply it to their lives.

28. Other Questions to Consider What role should dietary supplements play in meeting nutrient needs? What is cholesterol and why is it a nutritional concern? Discuss: What other questions did this chapter raise that you would like to explore? Discuss: What other questions did this chapter raise that you would like to explore?