Chapter 2

1. Chapter 2 Carbohydrates, Proteins, and Fats: The Energy Macronutrients of Balanced Meals

2. Learning Objectives • Describe the macronutrient content of various foods and meal items. • Describe the function and general recommendations for carbohydrate, protein, and fat in health prevention and disease management.

3. Macronutrients Macronutrients provide kilocalories (kcal), a measure of energy Carbohydrate (CHO) and protein (PRO) = 4 kcal/g Fat = 9 kcal/g Alcohol (EtOH) = 7 kcal/g; alcohol is not considered macronutrient

4. Macronutrients (continued) Macronutrients are organic—they all contain carbon Fats contain more carbon, thus being higher in kilocalories Being organic, all three macronutrients are digestible—they can break down into component molecules All three macronutrients contain carbon, hydrogen, and oxygen

5. Foods Generally Contain a Combination of Macronutrients

6. Carbohydrates Made up of glucose molecules: C6H12O6 Three basic forms: Sugar: monosaccharides and disaccharides Starch: polysaccharides Fiber: indigestible polysaccharide Two sources: Plants (from photosynthesis) Milk Chief energy source for the body cells (sugar and/or starch)

7. Examples Sugar is noted with suffix “ose”: glucose = blood sugar; sucrose = table sugar; fructose = fruit sugar; lactose = milk sugar Glucose and fructose = monosaccharides Starch = polysaccharide; found in bread, peas, corn, pasta, and potatoes (digested similarly to sugar) Fiber = indigestible polysaccharide found in plants; insoluble = skin and seeds and “crunchy” components; soluble = pulp and “gummy” components High-fiber foods have a relatively low glycemic index Glycemic load: a meal with a high content of CHO with sources that are high in glycemic index (quickly enter the bloodstream)

8. Whole Grains Contain the Entire Kernel (Bran, Germ, and Endosperm) Make at least half your grains whole

9. Food Label Guidelines 60% kcal as CHO (300 g per 2000 kcal) Total CHO = sum of sugar, starch, and fiber Fiber goal = 25 g per 2000 kcal Net CHO = total CHO minus fiber and 1/2 sugar alcohols *RDA for CHO: 130 g

10. Estimating CHO Content of Plant-Based Foods Assess 3 aspects of sensory experience of food: Level of sweetness Level of water Density ½ cup fruit (sweet): 15 g CHO ½ cup dry grains and dry (potato, legumes) or “sweet” vegetables (sweet corn, sweet peas): 15 g CHO 3 cups popcorn (low density): 15 g CHO ½ cup cooked or 1 cup raw low-CHO vegetables: 5 g CHO, (most low CHO vegetables sound odd to say, “sweet _____”) ½ cup flour (very dry): about 45 g CHO ½ cup sugar (very dry and very sweet): about 100 g CHO

11. Carbohydrate Counting http://coursewareobjects.elsevier.com/objects/elr/Peckenpaugh/essentials11e/video/CHO.html

12. Sugar Guidelines • American Heart Association Guideline • Less than 25g of sugar/day (100kcal) for women • Less than 37g of sugar/day (150kcal) for men

13. Protein Attributes and Functions Protein is unique among nutrients because it contains nitrogen Because of its nitrogen content, protein is used as a building source for new body cells Protein is found in all body cells and constituents such as the immune system, hormones, and digestive enzymes Dietary intake digested into amino acids; the liver reassembles these into protein

14. Protein Sources Found in muscle (i.e., red and white meats and fish), eggs, nuts, legumes, milk, and milk products Limited amounts in grains and vegetables Only fats and sugars do not contain protein; fruit contains only trace amounts of protein and is generally considered to have none Essential amino acids (EAA)—eight required for adults, nine for children with need for histidine; certain quantity needed in the diet within a 24-hour period to make protein Complete protein source: a food containing adequate amounts of all eight EAAs (animal products) High-biologic value diet: emphasizes foods with all EAAs

15. Protein Needs Minimum of 50 g daily Individualized needs based on age and other factors Infants: 2.24 g/kg body weight (BW) Children: 1.5 g/kg BW Adults: 0.8 g/kg BW Older adults 1.0 to 1.2 g/kg BW Athletes: 1.0 to 2.0 g maximum per kg BW Increased needs also based on health parameters (e.g., protein status or states of increased demand, such as with burns) Generally 15-25% of calories from protein

16. Protein Deficiency Conditions Reduced albumin (<3.5 mg/dL) related to impaired body processes; (<2.8 mg/dL related to poor surgical outcomes with impaired wound healing and compromised immune system) Albumin is also affected by inflammation, certain drugs, liver disease, fluid status, kidney disease, etc…& is NOT a reliable marker of malnutrition! Kwashiorkor: condition of protein deficiency Marasmus, or protein-calorie malnutrition (PCM)

17. Kwashiorkor and Marasmus/PCM (Right) Infant with “sugar baby” kwashiorkor, attributed to a high-sugar, low-protein diet. The infant has stunted growth, edema of the feet and hands, fatty liver, moon face, and dyspigmentation of the skin and hair. (Left) Normal infant. (From Jellife DB: Hypochromotrichia and malnutrition in Jamaican infants, J Trop Pediatr 1:25, 1995; by permission of Oxford University Press.) Marasmus. (From Zitelli BJ, Davis HW: Atlas of pediatric physical diagnosis, ed 4, Philadelphia, 2002, Mosby.)

18. Estimating Protein Content of Foods 1 oz meat (equals ¼ cup volume) = 7 g PRO 1 egg (¼ cup volume) = 7 g PRO ½ cup legumes, ¼ cup nuts, ¼ cup cheese (1 oz) and 1 tbsp peanut butter are counted as alternative to 1 oz meat 1 cup milk = 8 g PRO

19. Protein and Fat http://coursewareobjects.elsevier.com/objects/elr/Peckenpaugh/essentials11e/video/PRO.html

20. Fat (Lipids) Constituent of body cell membranes: phospholipids Essential fatty acids needed for hormonal production (e.g., linoleic acid, an omega-6 fatty acid; alpha linolenic acid, an omega-3 fatty acid) Solid = saturated fats; liquid = unsaturated fats (monounsaturated and polyunsaturated)

21. Foods Contain All Three Kinds of Fats: The Proportion Dictates the Texture Degree of saturation in common foods (in percentages). Percentages are based on the total amount of saturated, monounsaturated, and polyunsaturated fats. Purple, Saturated fat; green, monounsaturated fat; orange, polyunsaturated fat. (Reference for fat content modified from U.S. Department of Agriculture, Agricultural Research Service, 2005. USDA National Nutrient Database for Standard Reference, Release 18.)

22. Degree of Saturation Can Be Determined by Texture at Cold Temperature General amounts of saturated fats, monounsaturated fats, and polyunsaturated fats can be determined by appearance when fats are chilled. Note that solids are on the bottom of avocado and olive oils.

23. Food Label Guidelines Fat based on 30% kcal (65 g/2000 kcal) Saturated fat based on 10% kcal (20 g/2000 kcal) Trans fatty acids now listed; goal to have intake as minimal as possible Made from the addition of hydrogen to liquid oils; first commercial use of margarines and shortenings in the 1940s

24. Food Sources of Fat Found in germ portion of grains, some fruits (e.g., coconut, avocado, olives), and in whole milk (including butter), meats (including lard), nuts and seeds, egg yolks Omega-3 fatty acids (found in cold-water fish) essential for brain development; plant forms include flax, walnuts, canola oil Monounsaturated fats are preferred source for health (olive, canola oil and peanut oil, olives and most nuts, avocado)

25. Putting it into Perspective • How much fat is in your food? • Biscuit with egg and sausage: 39g=8 tsp • Large french fries: 29g=6 tsp • Tuna salad 6 inch sub: 29g=6 tsp • Chicken filet sandwich: 29g=6 tsp • 8 oz prime rib: 39g=8 tsp • 1 cup vanilla ice cream: 24g=5 tsp • ½ cup cheese dip: 24g=5 tsp • 1 cup pasta with alfredo sauce: 17g:3.5 tsp

26. Cholesterol A fatlike substance produced in the liver Found only in animal fat Not a kilocalorie source Necessary for normal body functioning Saturated fats can encourage excess production of cholesterol by the liver; unsaturated fats suppress the liver’s production of cholesterol; these processes are reflected in blood cholesterol levels To be discussed with review of Chapter 7

27. The Food Exchange System A food guide originally developed by the American Diabetes Association and the American Dietetic Association for diabetes management Generally no longer advised for diabetes management but useful to recognize the macronutrient content of foods (carbohydrate, protein, and fat)

28. Macronutrient Content of Food Exchanges (Per 1 Serving on Average)

29. Basal Metabolic Rate Amount of energy (kcal) required for basic processes of life Approximately 1200-1400 kcal for women Approximately 1600-1800 kcal for men Harris Benedict equation for BMR: Women: BMR = 655 + ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years ) Men: BMR = 66 + ( 6.23 x weight in pounds ) + ( 12.7 x height in inches ) - ( 6.8 x age in year )

30. Menu Planning Using Food Exchanges Example: Goal 2000 kcal at 55% CHO, 15% PRO, 30% fat2000 kcal × 0.55 = 1100 kcal/4 = 275 g CHO2000 kcal × 0.15 = 300 kcal/4 = 75 g PRO2000 kcal × 0.30 = 600 kcal/9 = 66 g fat

31. Study Guide • Vocabulary • Macronutrient • Sugar • Starch • Fiber • Glycemic index • Glycemic load • Complete protein • High biologic value diet • Soluble fiber • Albumin • Kwashikor • Marasmus • Saturated fat • Unsaturated fat • Trans fat • Essential amino acid • Omega 3 fatty acid • Insoluble fiber

32. Study Guide (continued) • How many calories per gram of protein, fat, carbohydrates and alcohol? • Why are fats higher in calories? • Basics of carbohydrates (slide 6) • Approximately what % of grains should be whole grains? Why are they important? Are multigrain breads whole grain? • Name the 3 parts of a whole grain • How many grams of fiber is recommended? Why is fiber important? • How many grams of CHO per serving? • Food sources of carbohydrates • What makes protein unique compared with CHO and fat? • Is albumin a good nutritional marker? Why? • Why is fat important? • Food sources of cholesterol (plant or animal based?)