This preview shows page 1. Sign up to view the full content.
Unformatted text preview: Got Milk?
Chapter 12 What is Nutrition? Science of food and how the body uses it Calorie = energy content of food 6 Essential Nutrients We need to get these from our diet Our bodies can't make them at all or can't make enough Carbohydrates Fats Proteins Vitamins Minerals Water Energy Sources Carbohydrates (CHO) In foods: Simple: fruits, milk, sugary foods, candy, soda Complex: whole grains, potatoes, legumes (dried beans & peas), some vegetables "Glucose" (in the blood) "Glycogen" (stored in the liver and muscle) The brain, nerve cells, blood cells The muscles (physical activity) In the body: Energy for: Whole Wheat Kernel Dietary Fiber Type of complex carbohydrate from plants Impossible or difficult for humans to digest Lowers blood cholesterol Plant foods, esp. fruit, legumes, oats/oat bran Prevents constipation, hemorrhoids, and maybe even colon cancer Whole wheat, wheat bran, cereals, grains, vegetables Soluble fiber: Insoluble fiber: Lack of fiber + refined carbohydrates = risk of diabetes 25-38 grams fiber per day Recommended CHO Intake Total CHO 6-11 servings of breads, cereals, etc. PLUS 5-9 servings of vegetables and fruits, OR 50-75% of total daily calories <10% of total daily calories Only in moderation Simple CHO (refined carbohydrates, sugars) You do the math...
2000-calorie Diet 60% of calories total from CHO: .60 x 2000 cal = 1200 cal Total CHO 10% of calories from simple CHO: .10 x 2000 cal = 200 cal Simple CHO 4 cal / gram of CHO: 1200 cal 4 cal/g = 300 g Total CHO 200 cal Simple CHO 4 cal/g = 50 g Simple CHO Fats Most concentrated source of energy Aid absorption of fat-soluble vitamins Vitamins A, D, E, K Provide energy for low to moderate intensity activity Insulate and protect body organs Regulate: estrogen production, blood pressure, nerve growth in children Saturated Fats Solid at room temperature Raise LDLs ("Lousy", or bad, cholesterol) in your blood Meats, whole milk, cheese, and butter Palm and coconut oils Aim for foods with 0 or 1 gram of saturated fat/serving Hydrogenated fats (found in the list of ingredients, often as "partially hydrogenated oil") Most margarines, shortenings, and peanut butters (the non "natural" peanut butters) Fried fast foods, fried chicken and fish, and fried snacks and chips Salad dressings Biscuits, rolls, cakes, crackers Cookies, doughnuts Any food with "hydrogenated oil" will contain some trans fatty acids Trans fats (found on Nutrition Facts panel) Unsaturated Fats Liquid at room temperature Monounsaturated:
Raise HDLs ("Healthy", or good, cholesterol) in blood Olive, canola, and peanut oils Most nuts, nut oils, avocado Polyunsaturated:
Lower LDLs (bad) and HDLs (good) in blood Sunflower, corn, soybean, and safflower oils Essential Polyunsaturated Fats Used to make hormone-like substances in the body that regulate many body functions Found in oils of plants and cold-water fish Omega-3 fatty acids: linolenic acid, EPA, DHA Canola and soybean oils, walnuts, wheat germ, soybean Nuts and seeds Mackerel, salmon, anchovy, sardines, herring, tuna, and lake trout Human milk (breastfeeding) Leafy vegetables, seeds, nuts, grains, vegetable oils Omega-6 fatty acids: linoleic acid Fish Oil Supplements are generally NOT recommended The Bottom Line on Fats & Cholesterol Saturated, hydrogenated, and trans fats Unhealthy Raise your LDL cholesterol Help improve (raise) your HDL cholesterol and are essential for a wide variety of body/cell functions Found only in foods that come from animals Monounsaturated, Omega-3, and Omega-6 fats Healthy Dietary Cholesterol Not Essential Blood Cholesterol a sterol (steroid) carried in the blood by a fat-protein complex HDL ("High-density" or "Healthy") LDL ("Low-density" or "Lousy") VLDL ("Very Low-density", also "Lousy" how triglycerides/fats are carried in the blood) Recommended Fat Intake Total Fat: 20-35% of total daily calories, OR <65 grams of fat/day 0-10% of total daily calories, OR <20 grams of saturated fat/day 0-300 mg/day Saturated Fat: Cholesterol: You do the math...
2000-calorie Diet 25% of calories from Fat: .25 x 2000 cal = 500 cal Total Fat 10% of calories from Saturated Fat: .10 x 2000 = 200 cal Saturated Fat 9 cal / gram of Fat: 500 cal 9 cal/g = 56 g Total Fat 200 cal Sat Fat 9 cal/g = 22 g Saturated Fat Proteins Composed of amino acids (building blocks) There are 9 essential amino acids We cannot store protein, except in the form of body tissue Form muscles, bones, blood, enzymes, hormones, antibodies, and cell membranes Cell repair Fluid and electrolyte balance For energy only in last resort (from body's own tissue) Purposes: Proteins in Our Diet Incomplete: Do not supply all 9 essential amino acids (a.a.) Legumes, nuts, whole grains Egg whites, meat, fish, poultry, milk, cheese, soy Complementary proteins 2 incompletes make a complete protein Complete: Supply all essential a.a. e.g. combining peanut butter with whole wheat bread Recommended Protein Intake 0.8 1.0 gram per kilogram of body weight = 0.36 0.45 gram per pound of body weight 2-3 servings of beans, peas, eggs, or lean meats, AND 2-3 servings of low-fat dairy More for growing children and pregnant and lactating women You do the math...
150-lb College Student 2.2 lb / kg of body weight: 150 lb 2.2 lb/kg = 68 kg 0.8 1.0 g protein / kg body weight: 0.8 g/kg x 68 kg = 54 g protein 1.0 g/kg x 68 kg = 68 g protein Vitamins Promote chemical reactions in living cells No calories (no energy) Types: 13 essential vitamins (p. 339) Fat-soluble: Vitamins A, D, E, and K Water-soluble: Vitamins C and B (8 B-vitamins) Vitamins E & C Beta-carotene (a precursor to Vitamin A) Antioxidants: Vitamins Sources: Fruits, vegetables, grains, and fortified foods Deficiencies
Anemia, fatigue, weakness Nervous system damage Health Effects: Excesses In general, it is best to get your vitamins from foods as opposed to supplements Minerals Regulate body functions Growth and maintenance of body tissues No calories (no energy) 17 essential minerals (p. 341) Most common deficiencies in Americans: Iron, calcium, zinc, magnesium Lean meats, fish, dark green vegetables, whole grains, lowfat dairy products Major sources: Water Digestion and absorption of nutrients (including water-soluble vitamins) Blood, fluids, lubricants, regulate body temperature Need ~2 liters/day (= 8 cups) If you're thirsty, you're already dehydrated Can you get sick or die from drinking too much water? Nutritional Guidelines Recommended Dietary Allowances (RDAs) Food labels To prevent nutritional deficiencies in most healthy people (minimum requirement) To prevent nutritional deficiencies To reduce risk of chronic disease A practical, balanced food-group plan including all essential nutrients Dietary Reference Intakes (DRIs) My Pyramid (p. 350, 352; Links on BB) Supplementation Recommendation by the American Medical Association (JAMA, June 2002) All adult Americans should take a daily supplement of vitamins and minerals Folic acid, B6, B12 (B vitamins) Vitamin D Antioxidants: Vitamins A, C, and E Challenges for Special Populations Women: More calcium and iron At least 3 or more servings of calcium-rich foods More fruits, vegetables, and grains Tend to eat convenience foods Tend to overeat Try to eat moderate portion sizes, and make more nutritious choices for convenient and inexpensive foods Men: College students: Sugar in Sodas and Most Juices One 12-oz soda = 39 grams of sugar = 8-10t of sugar = 156 calories One soda/day = 1.2-1.5 cups sugar/week = 1100 calories/week = 1 lb of body fat/3 weeks ...
View Full Document
- Spring '08