Your body’s need for nutrients

1. Your body’s need for nutrients

2. Lesson objectives: • Describe the role of fat in maintaining good health. • Identify food sources for fats. • Define cholesterol and explain its relationship to overall health.

3. Overview on nutrients • Nutrients: • Perform life-sustaining functions in body • Digestion: food broken down, released and absorbed; blood carries nutrients to cell where needed • Nourish body in 3 main ways: • 1) provide energy • 2) build, repair, maintain body tissues • 3) regulate body processes • More than 40 diff. nutrients attributed to good health • Grouped in 6 main categories: • Fats (today’s focus), proteins, vitamins, minerals, water, carbohydrates • Each has unique function in growth & function of body

4. Class fats activity: • Groups of four students • 1 brown bag and 8 food examples per group • Directions: • Rub each food example onto brown bag • Write what the food was under the rubbed area • When all foods have been rubbed, set bag aside to dry • We will return to this after the lesson

5. Fats overview: • Lipid – scientific term • Several important functions in health • Does not dissolve in water • Composed of same 3 elements as carbohydrates (carbon, hydrogen, oxygen) • Two types: saturated and polyunsatured • Chemical makeup determines which type

6. Chemical breakdown of fats . . . • Fats made up of fatty acids attached to glycerol molecule • Long chain of carbon, hydrogen, and oxygen • Saturated fatty acid: • Carbon chain holds all hydrogen that it possibly can

7. Chemical breakdown of fats (con’t) . . . • Polyunsaturated • Has two or more missing hydrogen atoms on carbon chain

8. Fatty acids differences: • 30 different fatty acids • Are neither fully saturated nor fully unsaturated • Mixture of both

9. Saturated fatty acids: • Foods with high proportion of saturated fats: • Animal fats and some vegetable oils • Pals, pals kernel, coconut, beef, pork, egg yolks, dairy (higher amounts) • Chicken, fish (lower amounts) • At room temperature: solid/semisolid • Processing: changes characteristics of fats • Hydrogenation: adding missing hydrogen to fatty acids • makes fat more saturated, firm at room temperature • I.E. margarine=hydrogenated vegetable oil • Want less of these fats in diet

10. Unsaturated fatty acids: • Most vegetable oils • Soybean, corn, cottonseed, etc. • At room temperature: liquid or oil form • Want more of these fats in diet

11. Roles of fats: • Important source of calories • Ounce for ounce: fats provide more than 2x the energy of carbohydrates or proteins • 30% of daily caloric intake = good health • Carry fat-soluble vitamins A, D, E, K into blood • w/out we could not use these nutrients • Provides essential fatty acids in diet • Body cannot create linoliec acid (essential for growth & healthy skin)

12. Dietary fat benefits: • Adds flavor • Satisfies hunger • Takes longer to digest than carbs and proteins • Body fat • Stored energy • Accumulates when more calories consumed from any source (carbs, fats, proteins) • Body needs fats to survive • Surrounds vital organs, cushions them from injury • Fat layer under skins insulated body from heat and cold

13. Sources of fats: • Almost every food has some fat • Visible fats • Butter, margarine, vegetable oil, fat layer on meat & poultry • Accounts for about 40% of fat in diet • Fats hidden in food • Marbled in meat; in chocolate, seeds, nuts, egg yolks, ice cream, cheese, cream soups, etc. • Food preparation • Frying , using sauces in cook

14. Cholesterol: • Fatlike substance resembling fat • Structurally different • Liver creates cholesterol • Not really considered a nutrient b/c of this fact • Essential part of cell membranes • Used to produce certain hormones • Vitamin D (in sunlight) • Protects nerve fibers • Lives uses it to make bile acids to aid digestion

15. Dietary vs. Serum cholesterol: • Dietary: • From food • Present on in food from animal origin • Meat, poultry, fish, eggs, dairy • Egg yolks and organ meats very high in cholesterol • Fruits, vegetables, grains, legumes, and other plant sources naturally cholesterol free • Serum (blood): • Circulated in blood • Some people create too much cholesterol • Risk factor for heart disease and circulatory diseases • Consuming too much contributes to elevated serum cholesterol

16. Return to class activity: • Have students look at brown bag • Which foods left a mark? • Why do you think they left this mark?

17. Wrap up . . . • Homework questions: • Name the three functions of fats. • What is cholesterol? What does it do? • Journal: start recording what you eat each day for one week. Circle foods that contain fiber. If fiber intake is lacking, work with teacher and parents to make plans to improve daily diet. • Clear/unclear statement handed in on way out of class.