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Chapter 9 Lecture Health: The Basics Tenth Edition Eating for a Healthier You Healthy Eating: An Overview • Hunger: The physiological impulse to seek food, prompted by the lack or shortage of basic foods needed to provide the energy and nutrients needed to support health • Nutrients: The constituents of food that sustain humans physiologically: proteins, carbohydrates, fats, vitamins, minerals, and water – MACROnutrients- Nutrients we need in large amounts- Carbs, Proteins, Fats – MICROnutrients- Nutrients we need in small amounts- Vitamins, Minerals • Appetite: The desire to eat normally accompanies hunger but is more psychological than physiological • Nutrition: The science that investigates the relationship between physiological function and the essential elements of foods eaten • Digestive Process: The process by which the body breaks down foods and either absorbs or excretes them © 2013 Pearson Education, Inc. Essential Nutrients for Health • Calorie: A unit of measure that indicates the amount of energy obtained from a particular food • We get energy from the calorie containing food we eat – Fat is the most concentrated source of energy and provides 9 calories per gram. – Carbohydrates and proteins contribute 4 calories per gram © 2013 Pearson Education, Inc. 6 Essential Nutrients for Health 1. 2. 3. 4. 5. 6. Water Proteins Carbohydrates Fats Vitamins Minerals Food provides the chemicals we need for activity and body maintenance. © 2013 Pearson Education, Inc. © 2013 Pearson Education, Inc. Water: A Crucial Nutrient • Humans can survive longer without food than without water. • Dehydration can cause serious problems within hours, and death within a few days. • The body consists of 50–60% water by weight. • Water is obtained through foods and beverages that are consumed. © 2013 Pearson Education, Inc. Proteins • After water, proteins are the most abundant substances in the body. – Used to repair bone, muscle, skin and blood cells, and are key elements of antibodies. – Proteins help transport iron, oxygen, and nutrients to all body cells. • Structure and Sources of Proteins – Amino acids are the building blocks of proteins; 9 of the 20 are essential because they must be obtained from food; the other 11 can be produced by the body. – Dietary protein that supplies all 9 essential amino acids is known as complete (high-quality) protein. – Proteins from plant sources lack one or more amino acids and are known as incomplete proteins. © 2013 Pearson Education, Inc. How Much Protein Do I Need? • The average American consumes more than 78 grams of protein daily, mostly from animal sources. • Recommended intake is only 0.8 grams protein per kilogram of body weight. – Divide your body weight by 2.2 to get your weight in kilograms – Then multiply by 0.8 – The typical recommendation for a 2,000 cal diet- 10% to 35% of calories should come from lean protein © 2013 Pearson Education, Inc. Carbohydrates • Are the best fuel source and provide energy quickly and efficiently. • Carbohydrates supply energy needed to sustain normal daily activity. They are metabolized faster and more efficiently than protein. • Carbohydrates are converted to glucose. • They play an important role in the functioning of the internal organs, the nervous system, and muscles and are the best fuel for endurance athletes. © 2013 Pearson Education, Inc. Forms of Carbohydrates • Simple Carbohydrates • • • • Glucose (monosaccharide)- simple sugars Fructose (monosaccharide)—fruit sugar Sucrose (disaccharide)—granulated table sugar Lactose (disaccharide)—milk sugar- the only simple sugar that comes from animals • Maltose (disaccharide)—malt sugar • Complex Carbohydrates (polysaccharides) • Starches—grains, cereals, and vegetables – Stored in the body as glycogen • Fiber—"bulk" or "roughage" © 2013 Pearson Education, Inc. What Carbohydrates Should I Eat? Which Should I Avoid? • Whole grains and high-fiber diets can protect against obesity, colon and rectal cancers, heart disease, constipation, and perhaps type II diabetes. • Choose foods such as brown rice, wheat, bran, and whole grain breads and cereals. • Increase fiber intake to 20–35 grams per day. • Eat fewer refined carbohydrates. © 2013 Pearson Education, Inc. Fats (Lipids) • Misunderstood but a vital group of basic nutrients that do the following: – – – – – – Maintain healthy skin Insulate body organs Maintain body temperature Promote healthy cell function Carry fat-soluble vitamins A, D, E, and K Supply a concentrated form of energy • Triglycerides make up 95% of total body fat. – When we consume too many calories from any source, the liver converts the excess into triglycerides, which are stored throughout our bodies. • Cholesterol makes up 5% of total body fat. – Can accumulate on inner walls of arteries and contribute to cardiovascular disease. – Ratio of cholesterol HDL/LDL helps determine risk for heart disease. © 2013 Pearson Education, Inc. Fat and Trans Fatty Acid • Types of Dietary Fat – Saturated are mainly from animal sources and are solid at room temperature. – Unsaturated generally come from plants and are usually liquid at room temperature. • Avoiding Trans Fatty Acid – Created by process of making liquid oil into a solid. – Increases LDL levels while lowering HDL levels. • Eating trans fat increases risk of coronary and heart disease and sudden cardiac death. – Found in many margarines, baked goods, and restaurant deep-fried foods. © 2013 Pearson Education, Inc. Is More Fat Ever Better? • Moderation is key. No more than 7 to 10% of your total calories should come from saturated fat and no more than 35% should come from all forms of fat. – Eat fatty fish. – Use healthier oils (including olive oil). – Eat green, leafy vegetables. – Eat walnuts and use walnut oil. – Eat ground flaxseed. © 2013 Pearson Education, Inc. Essential Nutrients for Health • To Reduce Your Overall Intake of Less Healthy Fats – – – – – – – – Read food labels. Use olive oil for cooking. Chill soups and stews and scrape off any fat that hardens. Hold the creams and sauces. Fill up on fruits and vegetables. Avoid margarine with trans fatty acids. Choose lean meat, fish, and poultry. Eat fewer cold cuts and less bacon, sausages, hot dogs, and organ meats. – Choose nonfat dairy products. – Use substitutes for higher-fat products. © 2013 Pearson Education, Inc. Vitamins • Potent, essential, organic compounds • Promote growth and help maintain life and health • Two Types – Fat soluble—absorbed through intestinal tract with the help of fats. A, D, E, and K vitamins are fat soluble and tend to store in the body. Toxic accumulations may cause cirrhosis-like symptoms. – Water soluble—dissolve in water. B-complex vitamins and vitamin C are water soluble. These are generally excreted and cause few toxicity problems. © 2013 Pearson Education, Inc. Antioxidants • Antioxidants – Often in functional foods – Most common are vitamin C, vitamin E, and betacarotene. – Free radicals damage or kill healthy cells. – Antioxidants scavenge free radicals, slow their formation, and repair oxidative stress damage. • Vitamin D – Formed when skin is exposed to the sun. – Improves bone strength, helps fight infections, lowers blood pressure. © 2013 Pearson Education, Inc. Minerals • Inorganic, indestructible elements that aid the body – Vitamins cannot be absorbed without minerals • Major minerals are needed in large amounts. – Sodium, calcium, phosphorus, magnesium, potassium, sulfur, and chloride • Trace minerals are needed in small amounts. – Iron, zinc, manganese, copper, and iodine – Excesses or deficiencies of trace minerals can cause serious problems. © 2013 Pearson Education, Inc. Sodium and Calcium • Sodium – Necessary for regulation of blood and body fluids, transmission of nerve impulses, heart activity, and certain metabolic functions. – Recommended consumption less than 1 teaspoon of table salt per day • Calcium – Plays a vital role in building strong bones and teeth, muscle contraction, blood clotting, nerve impulse transmission, regulating heartbeat, and fluid balance within cell. – Most Americans do not consume the recommended amount of 1,000 to 1,200 mg/day. © 2013 Pearson Education, Inc. Iron • The most common nutrient deficiency globally • Women aged 19 to 50 need about 18 mg per day. • Men aged 19 to 50 need about 10 mg. • Iron-deficiency anemia—body cells receive less oxygen, and carbon dioxide wastes are removed less efficiently. • Iron toxicity—ingesting too many ironcontaining supplements • Men who consume excess iron have a higher risk of gallstones. © 2013 Pearson Education, Inc. DRIs: Recommended Intakes for Nutrients • Dietary Reference Intake (DRIs): a list of 26 nutrients essential to maintaining health • Recommended Daily Allowances (RDAs): the reference standard for intake levels necessary to meet the nutritional needs of 97–98% of healthy individuals • Adequate Intake (AI): the recommended average daily nutrient intake level when there is not enough research to determine the full RDA • Tolerable Upper Intake Level (UL): the highest amount of a nutrient that an individual can consume daily without risk of adverse effects • Acceptable Macronutrient Distribution Range (AMDR): the range of intakes for carbohydrates, fat, and protein associated with a reduced risk of chronic disease, that provides adequate levels of essential nutrients © 2013 Pearson Education, Inc. How Can I Eat More Healthfully? • What Is a Healthful Diet? – A healthful diet should be • • • • • Adequate Moderate Balanced Varied Nutrient dense © 2013 Pearson Education, Inc. Dietary Guidelines for Americans, 2010 • MyPlate plan • Balance calories – Enjoy your food, but eat less. – Avoid oversized portion. • Foods to increase – Make half your plate fruits and vegetables. – Make at least half your grains whole. – Switch to fat-free or 1% milk. • Foods to reduce – Compare sodium in foods such as soup, bread, and frozen meals – choose foods with lower numbers. – Drink water instead of sugary drinks. © 2013 Pearson Education, Inc. MyPlate Plan © 2013 Pearson Education, Inc. How Can I Eat More Healthfully? (cont.) • Understand serving sizes • Eat nutrient-dense foods • Reduce empty calorie foods – Cakes, cookies, pastries, and donuts – Sodas, energy drinks, sports drinks, and fruit drinks – Cheese – Pizza – Ice Cream • Physical activity © 2013 Pearson Education, Inc. Serving Size Card © 2013 Pearson Education, Inc. Read the Labels • % Daily Value (%DV) • Other claims include – Nutrient content claims – Structure and function claims – Dietary guidance claims – Qualified health claims – Health claims © 2013 Pearson Education, Inc. Reading a Food Label © 2013 Pearson Education, Inc. Vegetarianism: A Healthy Diet? • Strict vegetarians, or vegans, avoid all food of animal origin. • Lacto-vegetarians eat dairy products but avoid flesh foods and eggs. • Ovo-vegetarians add eggs to the vegan diet. • Lacto-ovo vegetarians eat both dairy products and eggs. • Pesco-vegetarians eat fish, dairy products, and eggs. • With proper information and food choices, vegetarianism provides a superb alternative to meatbased cuisine. © 2013 Pearson Education, Inc. Supplements: Research on the Daily Dose • Dietary Supplements – Products taken by mouth to supplement existing diets – Include vitamins, minerals, and herbs – FDA does not evaluate supplements prior to their marketing; companies are responsible for their own monitoring. – A multivitamin added to a balanced diet will generally do more good than harm. © 2013 Pearson Education, Inc. Eating Well in College • If you must eat fast food – Ask for nutritional analyses of items. – Order salads, but be careful about what you add to them. – Avoid lard-based or other saturated-fat products and trans fats. – Avoid giant-sized portions, and refrain from ordering extras. – Limit beverages and foods high in added sugars. – At least once per week, add a vegetable-based meat substitute into your fast-food choices. © 2013 Pearson Education, Inc. ABC News Video: You Are What You Eat Discussion Questions 1. 2. 3. 4. Do you think it is a good idea for restaurants to post calorie content for the food on their menus? Would knowing the calorie content of a particular food keep you from ordering it? What are the goals of including calorie content of foods on restaurant menus? Why are "healthy" options in danger of being removed from restaurant menus? How can restaurants respond responsibly to progressive laws such as the one requiring the posting of calorie information on menus? © 2013 Pearson Education, Inc. Eating Well in College (cont.) • In the dining hall try this – Choose lean meats, grilled chicken, fish or vegetable dishes. Avoid fried foods. – Hit the salad bar and pick leafy greens, beans, tuna or tofu, and avocados or nuts. – Choose baked potatoes with salsa, or add grilled chicken to your salad. – At the made-to-order section, hold the butter, mayonnaise, sour cream or cheese, or cream-based sauces. – Avoid seconds, and pass on high-calorie, low-nutrient sweets. – Ask the food services manager about providing additional healthy options. © 2013 Pearson Education, Inc.