1. Nutrition Basics Chapter 12

2. The Body’s Nutritional Requirements • Essential nutrients • Are defined as nutrients one must obtain from diet (digestive system) b/c body does not mk. them in adequate amounts • The Six Essential Nutrients are: Proteins, Fats, Carbohydrates, Vitamins, Minerals, Water

3. The Body’s Nutritional Requirements • What is a Calorie (C)? • Defined as the amount of heat it takes to raise the temperature of 1L of water 1°C • Equal to 1 kilocalorie • Daily requirement: 2000 kilocalories • One pound is equal to: 3500 calories • Of the six essential nutrients, only three supply energy: • Fats supply = 9 calories/gram • Protein supply= 4 calories/gram • Carbohydrates supply= 4 calories/gram

4. Lipids (Fats) • There are three main classes of lipids: 1) Triglycerides (food fats) 2) Steroids and 3) Phospholipids • Triglycerides • Are a stored form of energy • Function: Insulation, support, absorption of fat-soluble vitamins (A,D,E & K) • Can be saturated or unsaturated • Saturated fats pack together to form solids at RT • Unsaturated fats do not pack as closely together forming liquid oils at RT

6. Fats and Your Health • Hydrogenation • A chemical reaction between hydrogen & another compound that increases the degree of saturation in unsaturated fats • Increases stability of fat • Trans Fatty Acids are formed in the process • Trans fatty acids are known to increase LDLs, and decrease HDLs

8. Which Foods Have Partially Hydrogenated Oils?

9. Fats and Your Health • Steroids • Cholesterol is a Steroid • Two main types of cholesterol: • HDL’s are High Density Lipo-Protein or “good” cholesterol • LDL’s are Low Density Lipo-Protein or “bad” cholesterol

10. Fats and Your Health • Beneficial Fats (polyunsaturated fats) • Omega-3 fatty acids • Found in some fish, nuts, vegetables • Reduces blood clotting, lowers TG’s • Alpha linolenic acid • Found in flax seed, canola, soy bean oils • Alpha lipoic acid • Acts as an antioxidant seeming to prevent cell damage • Found in heart, liver, kidneys, and vegetables such as broccoli and spinach.

11. Fats and Your Health • Recommended Intake • AMDRs = 20-35% (daily calories) • Healthy Fats are obtained from sources rich in unsaturated fats (flax, olive, canola, soybean, sunflower oils, sardines etc.) • Unhealthy/Less Healthy fats are obtained from sources rich in saturated fats (animal products, esp. red meat)

12. Fats and Your Health • Dangers of high fat diets • Difficulty managing weight • Obesity, heart disease, slower metabolism. • Increased risk of heart disease

13. proteins

14. Proteins • Proteins are the main components of muscle, bone, blood, enzymes, hormones and cell membranes etc. • There are Complete and Incomplete proteins • Complete proteins provide all essential amino acids (20) • Incomplete have most essential a.a.

15. Proteins • Recommended Intake • AMDRs =10-35% (daily calories) • Obtained from lean meat, poultry, fish, tofu, etc.

16. carbohydrates

17. Carbohydrates • Are Simple and Complex sugars • They provide fuel for cells • Two groups: • Simple Carbohydrates • Small (glucose) • Examples: glucose, lactose, sucrose (fruit, sugar, honey, milk) • Complex Carbohydrates • Larger • Examples: Starch and fiber (Grains, legumes,Tubers)

18. Complex Carbohydrates: Whole vs. Refined Grains • Grains before processing = Whole Grains • Whole Grains Contain: • Inner layer, (germ) • Middle layer, (endosperm) • Outer layer, (bran)

19. Complex Carbohydrates: Whole vs. Refined Grains • Grains after processing = Refined Grains • Germ and bran removed leaving starchy endosperm • Retains calories, lower in fiber, vitamins, minerals, etc.

20. A Closer Look at Fiber • Dietary fiber- nondigestible carbohydrates present in plants (grains, legumes, vegetables) • Functional fiber is isolated in a lab and added to food/dietary supplement • Fiber helps increase fecal bulk • Sources of fiber: all plant foods • Recommended intake = 38 grams (men) 25 grams (women)

21. The Glycemic Index • The Glycemic Index (GI) is a numerical scale used to indicate how fast and how high a particular food can raise our blood glucose (blood sugar) level • High glycemic index foods may increase appetite • May increase risk of diabetes and heart disease • Foods w/ a Low Glycemic index are whole grains, fruits, vegetables and legumes

22. Carbohydrates • Recommended carbohydrate intake • AMDRs = 45-65% (daily calories)

23. Vitamins • Organic (carbon-containing) micronutrient • Aid in chemical reactions; important in RBC production; some act as antioxidants • Humans need 13 vitamins: • Four Fat Soluble: A, D, E, and K. • Nine Water Soluble: C and B complex vitamins • (Thiamin, (B1), Riboflavin (B2), Niacin (B3), Pyridoxine (B6), Folate, B-12, Biotin and Pantothenic acid) • Sources: • Fruits, vegetables and whole grains

24. Minerals • Inorganic (noncarbon-containing) micronutrient • Help regulate body functions, growth & maintenance of body tissues • 17 essential minerals • Major minerals: needed in excess of 100 mg/day • (Ca 2+, P, Mg+, Na+, K+, Cl-) • Trace Minerals: needed in small amounts • (Cu, Fl, I, Fe, Se, Zn etc.)

25. Water • Human body = 50-60% water • Food and fluid intake provide 80-90%; metabolism provides the rest • Men need ~4 L (3 L from beverages);Women need ~3 L (2 L from bev.)

26. USDA’S My Plate • Key Messages • Make at least half of your grains whole grains • Make half your plate fruits and vegetables • Choose fat-free or low fat dairy as much as possible • Choose protein that is lean; choose skinless poultry • Drink water instead of sugary drinks • Physical activity every day!

27. Other substances in food • Antioxidants • Function: to protect the body from free radical damage • Examples: vitamin C, E, beta-carotene, lycopene • Antioxidants are phytochemicals, a naturally occurring substance in plant foods that may help prevent and treat chronic disease.

28. Food Safety • Causes of foodborne Illnesses: • Caused by pathogens, mainly bacteria • Fewer viruses • Can cause cramps, gastroenteritis, nausea, vomiting, etc. • Basic food safety principles • Clean hands, food contact surfaces and vegetables and fruits • Separate raw, cooked and ready-to-eat foods while shopping, storing and preparing foods • Cook foods to a safe temperature • Refrigerate perishable foods promptly

29. Food Safety • Environmental Contaminants • Contaminants in food growing environment • Examples: Minerals, antibiotics, hormones, pesticides industrial chemicals • Effects of contaminants depends on: • Concentration • Length of exposure • Age/status of person ingesting food

30. Food Safety • Organic foods • Limits on pesticide residues • Animals given organic feed; Animals have access to outdoors • No antibiotics or growth hormones given to animals • Genetic engineering is prohibited

31. Food Safety Try to Avoid: • Artificial Sweeteners • High Fructose Corn Syrup • Monosodium Glutamate • Trans Fat • Common Food Dyes • Sodium Sulfite • Sodium Nitrate/Sodium Nitrite • BHA And BHT Food Additives are Used to : (1) Maintain or improve nutritional quality (2) Maintain freshness (3) Help in processing or preparation (4) Alter taste and appearance

32. Types: Vegans only eat plant foods Lacto-vegetarians eat dairy and plant foods Lacto-ovo-vegetarians eat plants, dairy, and eggs Most plant proteins are not complete proteins A healthy vegetarian diet require a wide variety of plant foods to compensate Vitamin B-12 (only in animal products), vitamin D, calcium, iron , zinc Vegetarians

33. Dietary Guidelines for Americans • Eat a variety of nutrient-dense foods • Control calorie intake • Be physically active every day • Eat plenty of grains, vegetables and fruits • Choose fats wisely • Choose carbohydrates wisely • Use little salt and sugar • Moderation of alcohol consumption • Keep foods safe to eat