Lecture Outline Chapter 1 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. The Basics of Nutrition Chapter 1 Insert photo of mom & child in shopping cart from page 2 Chapter Learning Outcomes 1. Define terms such as diet, nutrition, nutrient, essential nutrient, macronutrient, micronutrient, kilocalorie, and photochemical. 2. Identify factors that influence personal food choices. 3. Identify lifestyle factors that contribute to the leading causes of death in the United States. 4. List the 6 classes of nutrients and identify a major role of each class in the body. 5. Identify basic metric system units often used in nutrition. Chapter Learning Outcomes (continued) 6. Explain the concept of energy density and identify energy-dense foods. 7. Use the caloric values of energy-yielding nutrients to estimate the amount of energy in a food. 8. Identify key basic nutrition concepts, such as the importance of eating a variety of foods and no food supplies all nutrients. 9. Discuss factors that contribute to malnutrition in the world. 10. Identify major federal U.S. food assistance programs. Quiz Yourself True or False 1. There are four classes of nutrients: proteins, lipids, sugars, and vitamins. T F 2. Proteins are the most essential class of nutrients. T F 3. All nutrients must be supplied by the diet, because they cannot be made by the body. T F 4. Vitamins are a source of energy. T F 5. Milk, carrots, and bananas are examples of “perfect foods” that contain all nutrients. T F How Did You Do? 1. False There are six classes of nutrients: carbohydrates, lipids, proteins, vitamins, minerals, and water. 2. False Proteins are not the most essential class of nutrients. 3. False All nutrients do not need to be supplied by the diet, because some can be made by the body. 4. False Vitamins are not a source of energy. 5. False Milk, carrots, and bananas are not “perfect foods.” No naturally-occurring food supplies all nutrients. What Influences Your Eating Habits? Insert figure 1.1 Why Should You Care About Your Diet? Poor diet is associated with 4 of 10 leading causes of death: -Heart disease -Some types of cancer -Stroke -Type 2 diabetes Adequate diet plus regular exercise may reduce your chances of developing these serious chronic diseases. Nutrition: The Basics Key Terms Nutrition Scientific study of nutrients, the chemicals in food that are necessary for life, and how the body uses them Nutrients Life-sustaining substances in food Diet Typical pattern of food choices Nutrition: The Basics Key Terms (continued) Chemistry Study of the composition and characteristics of matter and the changes that can occur to it Cell Smallest functioning structural unit in a living organism Six Classes of Nutrients 1. 2. 3. 4. 5. 6. Carbohydrates Lipids (includes fat) Proteins Vitamins Minerals Water Note approximate percentages of nutrients in young male and female bodies. Vitamins are not included, because they are in very small amounts. • Insert Figure 1.2 Major Functions of Nutrients in the Body Insert Table 1.1 Essential Nutrients and Nonnutrients Essential Nutrients -must be supplied by food -the body cannot synthesize or make enough of them Insert table 1.2 Three Features of Essential Nutrients 1. If missing from diet, a deficiency disease occurs. 2. Adding missing nutrient back to diet corrects signs and symptoms of the deficiency. 3. Scientists can explain why lack of the nutrient caused abnormalities. Nonnutrients Key Terms Fiber Group of substances made by plants that humans do not digest but produce some health benefits Phytochemicals Compounds made by plants that are not nutrients Nonnutrients Key Terms (continued) Antioxidants Substances that protect other compounds from being damaged or destroyed by certain environmental factors Phytochemicals of Scientific Interest Insert table 1.3 What Are Dietary Supplements? Dietary supplements include: - Nutrient preparations - Certain hormones - Herbs Echinacea Flower—the herbal supplement Echinacea is generally not useful for preventing or treating colds. FDA does not regulate dietary supplements as it regulates medications. Factors that Influence Your Health Your Lifestyle The way you live Your Risk Factors Personal characteristics that influence chances of developing disease Example: Lifestyle Poor diet and lack of regular exercise contribute to Excess Body Fat (Risk Factor) Our Changing Eating Habits Insert Table 1.4 Today, the typical American consumes more food energy, fat, and sugar than in 1970. Healthy People 2010 A report from the U.S. Public Health Service that includes 467 specific national health promotion and disease prevention objectives Insert table 1.5 Metrics for Nutrition Units of scientific measurement often used in nutrition Length — meters Weight — grams Volume — liters Insert table 1.6 Metrics for Nutrition Metric Basics (approximations) 1 inch = 2.5 cm 1 ounce = 28 g 1 pound = 454 g 2.2 pounds = 1 kg Do the Math If you are 5’5” (65”) (65 x 2.5 = 162.5 cm) If you weigh 130 lbs (130 ÷ 2.2 = approx. 59 kg) Metrics for Nutrition What’s a Calorie? calorie – measure of food energy; heat needed to raise 1 g of water 1o Celsius Kilocalorie or Calorie — measure of food energy – Technically a kilocalorie is the heat energy needed to raise the temperature of 1000 g (1 liter) of water 1o Celsius. Specific number of calories in food is reported as kilocalories or Calories 1 kilocalorie = 1000 calories = 1 Calorie Kilocalorie Contributors in Diets • 1 g of carbohydrate provides 4 kcal. • 1 g of protein provides 4 kcal. • 1 g of fat provides 9 kcal. • 1 g pure alcohol (a non nutrient) provides 7 kcal. Macronutrients and Micronutrients Macronutrients Micronutrients Needed in gram amounts and provide energy Needed in very small amounts and do not provide energy • Carbohydrates, protein, and fat • Vitamins and minerals Insert Table 1.7 Key Basic Nutrition Concepts Concept 1: Most Naturally Occurring Foods are Mixtures of Nutrients. A 6 oz potato contains: 4 g protein 36 g carbohydrate <1 g fat 8 fluid oz fat-free milk contains: 8 g protein 12 g carbohydrate 1 g fat Energy and Nutrient Composition These foods contribute very different amounts of energy, water, protein, carbohydrate, fat, and calcium to diets. Insert Figure 1.4 Concept 2: Eating a variety of foods can help ensure the nutritional adequacy of a diet. • There are no “perfect” natural foods that contain all nutrients in amounts needed by the human body. • Eat a variety of foods, especially fruits, vegetables, and minimally processed grains, to ensure nutritional adequacy. Concept 3: There are no “good” or “bad” foods. Empty Calorie versus Nutrient Dense Poor source of micronutrients (vitamins and minerals) compared to calories Has more micronutrients (vitamins and minerals) in relation to its energy value Concept 4: Enjoy eating all food in moderation Dietary moderation = Obtaining enough nutrients from food + Avoiding excessive amounts of nutrients + Balancing calorie intake with expenditure Concept: 5 For each nutrient, there is a range of safe intakes. • Insert Figure 1.7 Physiological dose Amount of a nutrient within the range of safe intake that enables the body to function optimally Megadose Generally defined as 10 times the recommended amount of a vitamin or mineral Concept 6: Food is the best source of nutrients and phytochemicals. During refinement, a wheat kernel is stripped of the nutrient-rich germ and phytochemical-rich bran. • Insert figure 1.8 Concept 7: There is no “One Size Fits All” approach to planning a nutritionally adequate diet. Food guides can be used to individualize your diet, so it is nutritionally adequate and suits your likes and dislikes. Concept 8: Foods and the nutrients they contain are not cure-alls. Specific nutrient deficiency diseases can be cured by eating foods that contain the missing nutrient. But, nutrients do not “cure” other ailments. Concept 9: Malnutrition includes UNDERnutrition as well as OVERnutrition Malnutrition State of health that occurs when the body is improperly nourished May be from inadequate or excessive amounts of nutrients Concept 10: Nutrition is a dynamic science. • As researchers continue to explore complex relationships between diets and health, nutrition information constantly evolves. • Even nutrition educators have difficulty keeping up with the vast amount of research published in scientific journals. Chapter 1 Highlight Malnutrition: A Worldwide Concern • Malnutrition – Improper nourishment • Chronic undernutrition – Long-term energy and nutrient deficiency - In children: stunted growth, delayed physical development, blindness, impaired intellectual development, and premature death • Hunger – Physiological need for food Factors that Contribute to Undernutrition • Insert figure 1.A Undernutrition • Affects ~ 1 in 3 people worldwide • More prevalent in: - Children - Underdeveloped countries • Insert figure 1.B Undernutrition During Life Cycle Stages - Pregnancy • Insert Figure 1.C - Infancy - Preschool years Effects of Malnutrition on Children Chronically undernourished children are underweight, do not grow normally, and tend to be shorter—if they survive to adulthood—than properly nourished children. Undernutrition in the United States Contributing factors: - Anorexia nervosa - Alcoholism - Low income Food insecurity: - Reported in 11% of U.S. households Insert Figure 1.D Major U.S. Food Assistance Programs • Insert Table 1.A Solutions Biotechnology Modifying living things (especially plants and animals) to make improved products Genetic Modification Techniques that alter an organism’s DNA Insert Figure 1.F