Select a vitamin or mineral and address the associated question

An Introduction to Nutrition

v. 1.0

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Table of Contents About the Authors………………………………………………………………………………………………….. 1 Acknowledgments ………………………………………………………………………………………………….. 3 Dedications …………………………………………………………………………………………………………….. 4 Preface……………………………………………………………………………………………………………………. 5 Chapter 1: Nutrition and You ………………………………………………………………………………… 9

Defining Nutrition, Health, and Disease ………………………………………………………………………………………. 12 What Are Nutrients? …………………………………………………………………………………………………………………… 18 The Broad Role of Nutritional Science…………………………………………………………………………………………. 26 Health Factors and Their Impact…………………………………………………………………………………………………. 36 Assessing Personal Health…………………………………………………………………………………………………………… 50 A Fresh Perspective: Sustainable Food Systems …………………………………………………………………………… 55 End-of-Chapter Exercises ……………………………………………………………………………………………………………. 63

Chapter 2: Achieving a Healthy Diet ……………………………………………………………………. 65 A Healthy Philosophy toward Food……………………………………………………………………………………………… 69 What Is Nutritional Balance and Moderation? …………………………………………………………………………….. 74 Understanding the Bigger Picture of Dietary Guidelines ……………………………………………………………… 82 National Goals for Nutrition and Health: Healthy People 2020 …………………………………………………….. 88 Recommendations for Optimal Health ………………………………………………………………………………………… 95 Understanding Daily Reference Intakes …………………………………………………………………………………….. 101 Discovering Nutrition Facts ………………………………………………………………………………………………………. 106 When Enough Is Enough……………………………………………………………………………………………………………. 115 Nutrition and the Media……………………………………………………………………………………………………………. 119 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 123

Chapter 3: Nutrition and the Human Body ……………………………………………………….. 125 The Basic Structural and Functional Unit of Life: The Cell …………………………………………………………. 128 Digestion and Absorption………………………………………………………………………………………………………….. 134 Nutrients Are Essential for Organ Function……………………………………………………………………………….. 142 Energy and Calories ………………………………………………………………………………………………………………….. 152 Disorders That Can Compromise Health ……………………………………………………………………………………. 156 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 163

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Chapter 4: Carbohydrates ………………………………………………………………………………….. 165 A Closer Look at Carbohydrates ………………………………………………………………………………………………… 169 Digestion and Absorption of Carbohydrates ………………………………………………………………………………. 176 The Functions of Carbohydrates in the Body……………………………………………………………………………… 188 Looking Closely at Diabetes ………………………………………………………………………………………………………. 194 Health Consequences and Benefits of High-Carbohydrate Diets …………………………………………………. 202 Carbohydrates and Personal Diet Choices………………………………………………………………………………….. 212 The Food Industry: Functional Attributes of Carbohydrates and the Use of Sugar Substitutes …….219 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 231

Chapter 5: Lipids ………………………………………………………………………………………………… 233 What Are Lipids? ………………………………………………………………………………………………………………………. 236 How Lipids Work ………………………………………………………………………………………………………………………. 243 Digestion and Absorption of Lipids ……………………………………………………………………………………………. 252 Understanding Blood Cholesterol ……………………………………………………………………………………………… 257 Balancing Your Diet with Lipids ………………………………………………………………………………………………… 263 Lipids and the Food Industry …………………………………………………………………………………………………….. 268 Lipids and Disease …………………………………………………………………………………………………………………….. 272 A Personal Choice about Lipids …………………………………………………………………………………………………. 276 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 281

Chapter 6: Proteins …………………………………………………………………………………………….. 282 Defining Protein ……………………………………………………………………………………………………………………….. 285 The Role of Proteins in Foods: Cooking and Denaturation………………………………………………………….. 293 Protein Digestion and Absorption……………………………………………………………………………………………… 296 Protein’s Functions in the Body ………………………………………………………………………………………………… 300 Diseases Involving Proteins ………………………………………………………………………………………………………. 308 Proteins, Diet, and Personal Choices………………………………………………………………………………………….. 314 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 333

Chapter 7: Nutrients Important to Fluid and Electrolyte Balance ……………………. 335 Overview of Fluid and Electrolyte Balance…………………………………………………………………………………. 338 Water’s Importance to Vitality………………………………………………………………………………………………….. 342 Regulation of Water Balance……………………………………………………………………………………………………… 346 Electrolytes Important for Fluid Balance …………………………………………………………………………………… 354 Consequences of Deficiency or Excess ……………………………………………………………………………………….. 373 Water Concerns ………………………………………………………………………………………………………………………… 378 Popular Beverage Choices …………………………………………………………………………………………………………. 389 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 402

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Chapter 8: Nutrients Important As Antioxidants ……………………………………………… 403 Generation of Free Radicals in the Body ……………………………………………………………………………………. 406 Antioxidant Micronutrients………………………………………………………………………………………………………. 413 The Whole Nutrient Package versus Disease ……………………………………………………………………………… 438 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 444

Chapter 9: Nutrients Important for Bone Health ……………………………………………… 445 Bone Structure and Function…………………………………………………………………………………………………….. 448 Bone Mineral Density Is an Indicator of Bone Health …………………………………………………………………. 455 Micronutrients Essential for Bone Health: Calcium and Vitamin D …………………………………………….. 457 Other Essential Micronutrients for Bone Health: Phosphorous, Magnesium, Fluoride, and Vitamin K ………………………………………………………………………………………………………………………………………………. 473 Osteoporosis …………………………………………………………………………………………………………………………….. 484 Risk Factors for Osteoporosis ……………………………………………………………………………………………………. 488 Osteoporosis Prevention and Treatment …………………………………………………………………………………… 493 Deficiency, Supplementation, and Choices ………………………………………………………………………………… 498 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 505

Chapter 10: Nutrients Important for Metabolism and Blood Function ……………. 507 Blood’s Function in the Body and in Metabolism Support ………………………………………………………….. 509 Metabolism Overview ……………………………………………………………………………………………………………….. 516 Vitamins Important for Metabolism and for Blood Function and Renewal …………………………………. 523 Minerals Important for Metabolism and for Blood Function and Renewal………………………………….. 537 Iron-Deficiency Anemia…………………………………………………………………………………………………………….. 545 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 552

Chapter 11: Energy Balance and Body Weight…………………………………………………… 553 Indicators of Health: Body Mass Index, Body Fat Content, and Fat Distribution…………………………..557 Balancing Energy Input with Energy Output ……………………………………………………………………………… 562 Too Little or Too Much Weight: What Are the Health Risks?………………………………………………………. 575 Dietary, Behavioral, and Physical Activity Recommendations for Weight Management ………………581 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 589

Chapter 12: Nutrition through the Life Cycle: From Pregnancy to the Toddler Years …………………………………………………………………………………………………………………… 591

The Human Life Cycle ……………………………………………………………………………………………………………….. 594 Pregnancy and Nutrition…………………………………………………………………………………………………………… 598 Infancy and Nutrition……………………………………………………………………………………………………………….. 614 Nutrition in the Toddler Years ………………………………………………………………………………………………….. 632 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 641

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Chapter 13: Nutrition through the Life Cycle: From Childhood to the Elderly Years …………………………………………………………………………………………………………………… 643

The Human Life Cycle Continues……………………………………………………………………………………………….. 646 Childhood and Nutrition …………………………………………………………………………………………………………… 651 Puberty and Nutrition ………………………………………………………………………………………………………………. 659 Older Adolescence and Nutrition ………………………………………………………………………………………………. 665 Young Adulthood and Nutrition………………………………………………………………………………………………… 670 Middle Age and Nutrition …………………………………………………………………………………………………………. 676 Old Age and Nutrition……………………………………………………………………………………………………………….. 681 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 687

Chapter 14: Nutrition and Society: Food Politics and Perspectives ………………….. 689 Historical Perspectives on Food ………………………………………………………………………………………………… 692 The Food Industry…………………………………………………………………………………………………………………….. 699 The Politics of Food…………………………………………………………………………………………………………………… 708 Food Cost and Inflation …………………………………………………………………………………………………………….. 714 The Issue of Food Security ………………………………………………………………………………………………………… 718 Nutrition and Your Health ………………………………………………………………………………………………………… 726 Diets around the World …………………………………………………………………………………………………………….. 732 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 744

Chapter 15: Achieving Optimal Health: Wellness and Nutrition ………………………. 746 Diet Trends and Health……………………………………………………………………………………………………………… 749 Fitness and Health ……………………………………………………………………………………………………………………. 763 Threats to Health ……………………………………………………………………………………………………………………… 770 Foodborne Illness and Food Safety ……………………………………………………………………………………………. 782 Start Your Sustainable Future Today…………………………………………………………………………………………. 797 Careers in Nutrition………………………………………………………………………………………………………………….. 802 End-of-Chapter Exercises ………………………………………………………………………………………………………….. 806

Chapter 16: Appendix A ……………………………………………………………………………………… 807

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About the Authors

Maureen Zimmerman

Dr. Maureen Zimmerman earned her undergraduate degree in Nutrition and Dietetics at Arizona State University, a Master’s Degree in Public Health from the University of Hawaii, and a Doctorate in Educational Leadership, with a specialization in educational research, from Northern Arizona University. She is a Registered Dietitian and has been a residential faculty member at Mesa Community College in Mesa, Arizona since 1991. She has been involved in many aspects of college life, most of them related to improving teaching and learning. She works indefatigably to assure that students enjoy their learning journey, regularly applying learning science to the online and ground classrooms. She is active every day of the week either practicing yoga, biking, hiking, tap dancing, or running. She enjoys reading a variety of genres, and likes to drink good coffee in the company of friends and family. She watches international films regularly, and tries to eat many fruits and vegetables every day. Her food first philosophy is summed up in this statement: “Enjoy real food, enjoy it with others, enjoy it in just the right amounts.”

Beth Snow

Dr. Beth Snow earned a BS (Hons) in Biochemistry (with a minor in Drama) from McMaster University in 1999, an MS in Human Biology & Nutritional Sciences from the University of Guelph in 2000, and a PhD in Human Nutrition from the University of British Columbia in 2006. She also holds a Credentialed Evaluator designation from the Canadian Evaluation Society. Her PhD research focused on the effects of prenatal alcohol exposure on the developing fetal skeleton and she has published in the journals Bone, Alcohol, and Alcoholism: Clinical & Experimental Research. Following her PhD training, she spent two years working at the British Columbia Centre of Excellence for Women’s Health, where she ran an interdisciplinary research training

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program. She currently works as an Evaluation Specialist in Public Health in Vancouver, BC, Canada, where she also teaches at the University of British Columbia and the Justice Institute of British Columbia. Her teaching philosophy involves empowering students to take ownership of their own learning; she uses active learning techniques and encourages students to apply what they learn to real life. Being a lifelong learner herself, Beth is currently working on a Masters of Business Administration at the University of British Columbia, with the goal of combining knowledge about organizations with her health research expertise in order to help get research evidence into Public Health practice. In addition to her busy career, Beth is a true foodie who always makes time to cook and share good food and she enjoys hiking, running, yoga, and, being a Canadian, playing ice hockey.

About the Authors

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Acknowledgments

It takes a village to create a textbook and we are deeply indebted to all those who helped us make this book a reality. First and foremost, our deepest thanks go out to all those who reviewed our chapters and gave us thoughtful feedback on how to make them even better:

• Patricia Abraham, Arkansas State University • Jessica Adams, Colby-Sawyer College • Christine Bieszczad, Colby-Sawyer College • Douglas Bruce, Laney College • Kathleen L. Deegan, California State University, Sacramento • Lindsay Edwards, Hardin-Simmons University • Cathy Headley, Judson University • Laura Hutchinson, Holyoke Community College • Christa Koval, Colorado Christian University • Beth Ann Krueger, Central Arizona College–Aravaipa Campus • Patrick Mathews, Friends University • Jill O’Malley, Erie Community College • Ana Otero, Emmanuel College • Alfred Ordman, Beloit College • Paula Vineyard Most, John A. Logan College • Linda Wright, Dixie State College of Utah

We are especially thankful to Teresa Fung for her expert content editing. Teresa has a keen eye for scientific accuracy. Because she is steeped in the nutrition literature, her input has been invaluable.

The development editors included Melissa Lingohr-Smith, Lisa Benjamin, and Danielle Dresden.

We are also very grateful for the incredible support we received from the teams at Unnamed Publisher and The Research Masters. Melissa Yu of Unnamed Publisher and Amy Bethea of The Research Masters have provided such invaluable support in managing the creation of this book—it could not have happened without them. We would also like to thank Michael Boezi and all the others at Unnamed Publisher who have championed a nonmajors nutrition book.

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Dedications

Maureen Zimmerman

Many people have shaped my professional and personal life. I would be remiss not to acknowledge those who saw potential and hired me in 1991 to develop a nutrition program at Mesa Community College. To those who initiated and maintained the stellar teaching and learning movement in the Maricopa Community College District, I am grateful. To my colleagues and the doctoral faculty who helped form my teaching practice, thank you. Succor comes from my family. My five children, in particular, experienced my nutritional philosophies even before the cradle. They brought hummus to school before it ever hit the grocery store shelves. Studying and teaching nutrition has been a fulfilling part of my life; I am grateful to all who have influenced me, most especially the thousands of students I have learned with through the years.

Beth Snow

I dedicate this book to my mother, Ann Snow, who taught me the fun of cooking, and my father, the late Jack Snow, who showed me the amazing world of biology. Marrying these two interests led to my pursuit of an education in nutritional sciences and, ultimately, to authoring this textbook.

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Preface

Welcome to Essentials of Nutrition: A Functional Approach! This book is written for students who are not majoring in nutrition, but want to learn about the fundamental aspects of nutrition and how it applies to their own lives. We have written this book with the assumption that you have little or no prior knowledge of college level chemistry, biology, or physiology. But that does not mean it’s not scientific! Nutrition is a science-based discipline, so all the material included is backed up by rigorous scientific research, but it is presented in a clear, easy-to- understand fashion without requiring a background in science.

Focus on Sustainability

People are increasingly interested in sustainable food issues. They are looking for favorable ways to impact not only their health, but also the environment and their local economy. However, misinformation about how one can make a positive impact abounds. By highlighting effective sustainable food behaviors, supported by science, this book will provide you with a significant resource for increasing the sustainable practices in your day-to-day life.

Organization

This book is organized using a functional approach, which means that the material is organized around physiological functions, such as fluid and electrolyte balance, antioxidant function, bone health, energy and metabolism, and blood health, instead of organizing it strictly by nutrient. This makes the information easier to understand, retain, and apply to your own life. As this text explores the relationship between nutrition and physiology, you will receive a “behind the scenes” examination of health and disease in the body.

• In Chapter 1 “Nutrition and You”, we provide an overview of nutrition as an evidence-based science and explore the concepts of health, wellness, and disease. We also provide an introduction to the different types of nutrients, health factors, personal health assessment, and the concept of sustainable food systems.

• In Chapter 2 “Achieving a Healthy Diet”, we explore the tools you can use to achieve a healthy diet, as well as important nutrition concepts like balance and moderation.

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• In Chapter 3 “Nutrition and the Human Body”, because we know that you may not have a background in biology, we start with a tour through the human body, from the single cell to the full organism, we set up for a discussion about the processes of digestion and absorption, followed by explorations of the other organ systems. After that, we discuss the concept of energy and calories. We also discuss some disorders and diseases related to nutritional health.

• In Chapter 4 “Carbohydrates”, we explore the many types of carbohydrates, including their functions. We also take a look at diabetes and at sugar substitutes.

• In Chapter 5 “Lipids”, we look at the types, structure, and roles of lipids, and we explain the different types of cholesterol in the blood. We also explore topics of interest such as omega-3 and omega-6 fatty acids and trans fats.

• In Chapter 6 “Proteins”, we cover the structure and roles of protein, and explore the consequences of getting too little or too much protein in your diet. Tips for getting the right amount and quality of protein, as well as a look at special populations, such as the elderly and athletes, are also covered.

• In Chapter 7 “Nutrients Important to Fluid and Electrolyte Balance”, we look at the nutrients important to fluid and electrolyte balance, including water, sodium, chloride, and potassium. We also look at sports drinks, caffeinated beverages, and alcohol.

• In Chapter 8 “Nutrients Important As Antioxidants”, nutrients important as antioxidants are explored, starting with an explanation of what oxidation and antioxidants are, then looking at vitamins E, C, and A, selenium, and phytochemicals.

• In Chapter 9 “Nutrients Important for Bone Health”, we delve into nutrients important for bone health. First, we explore the structure and function of bones, and then calcium, vitamin D, phosphorus, magnesium, fluoride, and vitamin K. A look at osteoporosis and at supplements rounds out this chapter.

• In Chapter 10 “Nutrients Important for Metabolism and Blood Function”, we look at the nutrients important in energy metabolism and blood health, by first looking at blood and at metabolism, and then discussing the B vitamins, vitamin K, magnesium, iron, zinc, and other micronutrients. We also explore iron-deficient anemia and iron toxicity.

• In Chapter 11 “Energy Balance and Body Weight”, we take a look at the obesity epidemic and eating disorders—the extremes of energy imbalance—and we look at evidence-based recommendations for maintaining a healthy weight.

• Chapter 12 “Nutrition through the Life Cycle: From Pregnancy to the Toddler Years” is the first of two chapters exploring nutrition through

Preface

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the life cycle and it looks at pregnancy through the toddler years. Topics include pregnancy, breastfeeding, introducing solid foods, and nutrition during the toddler years.

• In Chapter 13 “Nutrition through the Life Cycle: From Childhood to the Elderly Years” we continue to explore nutrition through the life cycle, this time looking at childhood to the elderly years.

• In Chapter 14 “Nutrition and Society: Food Politics and Perspectives”, we explore food politics, sustainability, the food industry, food security, and diets from around the world.

• In Chapter 15 “Achieving Optimal Health: Wellness and Nutrition”, we look at a number of topics of interest to students: diet trends, food supplements and food replacements, fitness, chronic diseases, and food safety. Also included in this chapter are tips for living a sustainable lifestyle, and information about careers in nutrition.

Features

Each chapter starts with a “Big Idea,” which provides a preview of the main theme of the chapter.

You Decide challenges you to apply what you are learning about nutrition topics—sometimes controversial ones—to your own life.

Key Takeaways and Key Terms provide the key take-home messages and definitions from each section, helping you to focus on the main points you should be learning.

Discussion Starters are questions that can prompt discussions with fellow students and your instructor to examine and extend what you’ve learned in the chapter.

There are many Videos available online and it is not always clear which ones have reliable information. We have done the legwork for you by providing interesting videos from reputable sources to accompany and highlight the content. Similarly, we provide links to useful online learning tools through the Interactive feature.

Most of the databases for diet analysis programs primarily feature industrial food. As we promote sustainable food activities in our text, we cannot use these common diet analysis programs because they do not cater to students who eat real food prepared at home. As a result, we provide links to http://www.choosemyplate.gov/ throughout the text. You will be encouraged to create your own meals, shop

Preface

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