Chapter 7

1. Chapter 7 Nutrition: Eating For Optimal Health

2. Many Dietary Choices • Exotic and foreign foods • dietary supplements • artificial sweeteners/flavors • no-fat, low-fat & artificial fats • cholesterol free, high protein, high- carbohydrate & low calorie

3. Healthy Eating • Hunger……..a physiological need to eat • Energy requirement in today’s society • work, school, history, preference • cultural preferences for FOOD • economic status • food security issues • Appetite…… desire to eat…..associated with hunger….more psychological…..

4. Nutrition Science of food • relationship between physiological function and essential elements in food Nutrients • proteins,carbohydrates (CHO), fats, vitamins, minerals & Water (H2O)

5. “Diets of Affluence” • high fat & calories • red meat / potatoes/ rich deserts • recent trends…..more white meats and more fruits and vegetables • BUT!!!!! Heart disease, cancer, hypertension, cirrhosis of the liver, tooth decay and chronic obesity……. ……..still major health risks! • A preoccupation of food • eating too much of the wrong foods • disordered eating

6. Responsible Eating: Changing Old Habits • Consume more calories then we need • calorie - a measurement of energy potential in food • CHO: 4 Kcal/g • FAT: 9 Kcal/g • PROTEIN: 4 Kcal/g

7. Nutrition PROCESS: nutrients are absorbed from the small intestine into bloodstream for use by cells metabolized into usable compounds for building/repair/muscular work.

8. NUTRITION IS IMPORTANTFOR………… • energy production for muscular work growth and synthesis of body materials • providing materials for tissue maintenance • regulation of bodily processes

9. The Digestive Process • Provides the body with chemicals for energy and body maintenance • essential nutrients delivered via food intake • broken down to be absorbed and delivered to cells 3,000,000,000,000

10. The Process……………………. Start: Mouth - salivary glands (saliva) - prepares food / moistens / breakdown Esophagus Tube:20 to 25cm - connects mouth to stomach Stomach: HCL acid + food + enzymes = mixture mucus lines stomach for protection Small Intestines: 8 meters long 3 parts - duodenum, jejunum & ileum secretes digestive enzymes + liver pancreas (Fats, Proteins + CHO)

11. Nutrients are Absorbed Into Blood The Liver: • determines destination - stored, sent to cells, organs or excreted The Large Intestine: solid wastes (fiber, water,salts etc)

12. The Calorie • Calorie: • a unit for measuring the energy of food - 1 calorie produces enough energy to raise the temperature of 1g of water 1 degree • caloric measurements are made in thousands of calories therefore the term calories is interchangeable with Kilocalories ( kcal.)

13. RDA (Recommended Dietary Allowance) • the levels of nutrient intake that is necessary for the maintenance of good nutrition of practically all healthy persons.

14. Factors causing variations in food requirements: • Age • sex • physical size • activity level • pregnancy • convalescence

15. Energy Balance Isocaloric Balance Positive Balance Negative Balance

16. CARBOHYDRATES (CHO’s) • compound consisting of carbon, hydrogen and oxygen (C6H12O6) • most efficient energy source both immediate and time released • average Canadian diet has 46% kcal from CHO; • energy yield = 4 Kcal/g.

17. Main function….. CHO’s • energy • also rich in vitamins, minerals, and water. • when CHO enters the body, it is converted to glucose, the energy source for cells (very important for nervous system and brain).

18. Categories of Carbohydrates: SIMPLE: c-c-c-c-c-c COMPLEX CHO: c-c-c-c-c-c-c-c-c-c-c-c-c-c-c-c-c- c-c-c-c-c-c-c-c-c-c-c-c

19. Simple Sugars • composed of one or two simple sugar units (fructose, glucose and galactose) • found mainly in fruitsprovide immediate energy

20. Two forms of simple sugar: Monosaccharides: • consist of one molecule of sugar - the structural unit of simple CHO (fructose, galactose, and glucose).

21. Disaccharide: combination of Monosaccharides includes sucrose, which is table sugar - combination of 1 fructose plus 1 glucose molecule Lactose (milk products) = 1 glucose plus 1 galactose molecule Maltose = 2 glucose molecules

22. PROCESSED SUGAR CONSUMPTION IN CANADA: Mean consumption for each Canadian over 15 years = 150 lbs. of sugar per year - 75% in form of processed foods and beverages • This represents more than 20-25% of caloric intake • 33 teaspoons of sugar per day = 6 stalks of sugar cane • tooth decay

23. DISADVANTAGES OF HIGH SUGAR INTAKE Processed sugars - poor CHO - contain no other nutrients i.e. no vitamins and minerals EMPTY CALORIES results in a situation where 100% of nutrients must be obtained from 75% of calories in the diet.

24. COMPLEX CHO (polysaccharides) • composed of three or more simple sugars bonded together • found in grains, fruits, stems, roots, and leaves of vegetables • provide longer lasting energy

25. Three Types of CHO Starches: plant source - whole grain foods, rice, potatoes Fiber (Cellulose): not digested by enzymes in small intestine insoluble: speeds movement of foods through digestive tract, increases fecal bulk and maintains regularity of bowel movement

26. CHO……... Soluble fiber: digested in the large intestine (fruits, veggies oat bran,dried beans) decreases blood cholesterol and cardiovascular disease Controls pacing of absorption of CHO into bloodstream. Prevents dramatic swings in blood sugar levels

27. Canadians Should double their intake of fiber, bulk, roughage…20 to 30 grams Protection against: • colon/rectal cancer • breast cancer • constipation • diverticulosis • heart disease • diabetes • obesity

28. Eat Less Processed Food to Increase Fiber Intake CARCINOGENS - ? • skins of fruits & veggies • fiber from food rather than pills/powder • spread out fiber intake • drink plenty of liquids

29. I’m soooo hungry I could eat a Vegetable!

30. EATING TOO MUCH CHO !CAN IT BE TRANSFORMED INTO FAT? Glycogen glucose molecules bonded together stored mainly in liver and muscle relatively fast energy for muscles • EATING TOO MUCH CHO CAN BE TRANSFORMED INTO FAT

31. FATS Many negative associations with fat essential for insulation and maintenance of body temperature padding healthy skin and hair proper cell function carrying of fat-soluble vitamins A, D, E, K to cells add flavor and texture to our food high-energy yield = 9 Kcal/g

32. Two major types:Triglycerides and Steroids • 95% of total fat in body • excess Kcal are converted to Triglycerides and stored in adipose tissue (fat cells) • each triglyceride is composed of three fatty acid molecules attached to one glycerol molecule • fatty acids consist of a chain of hydrogen (H) and carbon (C) atoms, with a few oxygen (O) atoms

33. Triglycerides some Triglycerides are a major concern because of the type of fatty acid they contain……... fatty acids can be saturated or unsaturated (monounsaturated or polyunsaturated)

34. SATURATED FATS: • chains containing the maximum number of H atoms • solid at room temperature - butter, lard etc., usually animal fat • associated with increased cholesterol levels.

35. UNSATURATED chains able to hold more H atoms plant fats, usually liquid at room temperature if room for only 1 H atom = monounsaturated if room for more than 1 H atom = polyunsaturated both mono- and polyunsaturated appear to lower total blood cholesterol

36. Steroids (cholesterol): essential in formation of: • Vitamin D • sex hormones (androgen, estrogen and progesterone) • protects nerve fibers

37. Lipoproteins • transport mechanism for cholesterol in blood • three types of lipoproteins • HDL • LDL • VLDL

38. HDL (High Density Lipoproteins) • transports circulating cholesterol from blood to liver for metabolism and elimination from body • the "good" cholesterol • help protect against coronary artery disease

39. LDL (Low Density Lipoproteins) and VLDL (Very Low Density Lipoproteins) • transport cholesterol from digestive tract to blood - "bad" cholesterol • associated with an increase risk of coronary artery disease Exercise HDL, LDL + VLDL, ratio of LDL/HDL

40. PROTEINS • carbon (C), hydrogen (H), oxygen (O), and nitrogen (N) • essential for growth, maintenance, and regulation of body tissues and processes • all living organisms contain protein • major component of all cells • help build muscle, bone, skin, and blood

41. Proteins • major constituent of antibodies, essential part of immune system • aid in formation of hormones such as insulin and thyroxin, which regulate metabolism • essential for enzyme formation • high energy yield = 4 Kcal/g • when CHO or Fat are insufficient, protein can be used as an energy source at expense of tissue growth

42. Proteins • extra protein ingested will be broken down to be used as calories or converted into body fat • proteins are formed from varying combinations of 20 (21, 22 or 23) amino acids • amino acids are linked together in a string and form proteins • amino acids are linked in various combinations to form various types of proteins

43. Proteins • body makes all but 8 amino acids - called essential amino acids must come from diet (milk products, poultry, fish) • animal protein contains significant amounts of 8 essential amino acids, but also contain saturated fat and cholesterol • any food containing all 8 essential amino acids is known as complete protein

44. Proteins • no source of vegetables or cereal protein provides all 8 essential amino acids • 3 combinations of incomplete protein which make complete protein 1. grains and legumes 2. grains and milk products 3. seeds and legumes

45. Protein Ways to ensure adequate protein intake………... eat a varied diet containing all three nutrients: proteins, carbohydrates and fat; if insufficient kcal from carbohydrates and fat = body uses proteins…. AND How Much Protein Should I Eat??????

46. Years Sex protein • (g/kg body wt) • 16-18 M 0.88 • F 0.81 • >19 M 0.82 • F 0.74 • Adult male of 70 kg (above 19 years) should eat 70 X 0.82 or 57.4 g/day • 2 glasses of milk • 2 eggs • 4 ounces of meat • Canadians eat approximately 90 g/day 2 X RDA *** excess stored as fat or used as energy Are YOU Eating Enough protein? Athletes 1.5 g/kg body wt

47. VITAMINS, MINERALS, WATER VITAMINS • complex organic substances found in food, or chemically made, that are essential in small amounts for bodily processes • no difference found in food or chemically made • do not provide energy but play a role in metabolism • deficiency diseases result when inadequate amounts are consumed

48. Grouped According to Solubility Water Soluble not stored in the body, need to be replaced daily These are………. B-group and Vitamin C

49. Fat Soluble Vitamins………. stored in the body and can reach toxic levels if consumed in megadoses (many times the RNI) Recommended Nutrient Intake Vitamins A, D, E, K can act as antioxidants – may slow down the destruction of cells

50. MINERALS • inorganic elements essential for body function/regulation components of hormones /enzymes • function with vitamin absorption • their potency can be destroyed by various means - heat, baking soda, etc.