Human Nutrition 2020 Edition PDF

Human Nutrition: 2020 Edition  Human Nutrition: 2020 Edition UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM ALAN TITCHENAL, SKYLAR HARA, NOEMI ARCEO CAACBAY, WILLIAM MEINKE-LAU, YA-YUN YANG, MARIE KAINOA FIALKOWSKI REVILLA, JENNIFER DRAPER, GEMA...

Human Nutrition: 2020 Edition  Human Nutrition: 2020 Edition UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM ALAN TITCHENAL, SKYLAR HARA, NOEMI ARCEO CAACBAY, WILLIAM MEINKE-LAU, YA-YUN YANG, MARIE KAINOA FIALKOWSKI REVILLA, JENNIFER DRAPER, GEMADY LANGFELDER, CHERYL GIBBY, CHYNA NICOLE CHUN, AND ALLISON CALABRESE Human Nutrition: 2020 Edition by University of Hawai‘i at Mānoa Food Science and Human Nutrition Program is licensed under a Creative Commons Attribution 4.0 International License, except where otherwise noted. Contents Preface xxv University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program About the Contributors xxvi University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Acknowledgements xl University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part I. Chapter 1. Basic Concepts in Nutrition Introduction 3 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Food Quality 14 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Units of Measure 18 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Lifestyles and Nutrition 21 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Achieving a Healthy Diet 30 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Research and the Scientific Method 34 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Types of Scientific Studies 41 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part II. Chapter 2. The Human Body Introduction 55 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Basic Biology, Anatomy, and Physiology 62 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Digestive System 68 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Cardiovascular System 82 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Central Nervous System 94 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Respiratory System 99 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Endocrine System 106 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Urinary System 110 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Muscular System 117 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Skeletal System 120 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Immune System 129 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Indicators of Health: Body Mass Index, Body Fat 133 Content, and Fat Distribution University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part III. Chapter 3. Water and Electrolytes Introduction 145 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Overview of Fluid and Electrolyte Balance 150 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Water’s Importance to Vitality 156 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Regulation of Water Balance 162 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Electrolytes Important for Fluid Balance 172 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Sodium 176 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Chloride 190 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Potassium 195 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Consequences of Deficiency or Excess 199 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Water Concerns 209 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Popular Beverage Choices 216 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part IV. Chapter 4. Carbohydrates Introduction 229 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Digestion and Absorption of Carbohydrates 240 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Functions of Carbohydrates in the Body 253 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Health Consequences and Benefits of High- 260 Carbohydrate Diets University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Carbohydrates and Personal Diet Choices 271 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part V. Chapter 5. Lipids Introduction 291 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Functions of Lipids in the Body 296 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Role of Lipids in Food 301 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program How Lipids Work 305 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Nonessential and Essential Fatty Acids 313 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Digestion and Absorption of Lipids 319 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Tools for Change 331 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Lipids and the Food Industry 340 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Lipids and Disease 345 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program A Personal Choice about Lipids 351 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part VI. Chapter 6. Protein Introduction 359 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Defining Protein 363 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Role of Proteins in Foods: Cooking and 374 Denaturation University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Protein Digestion and Absorption 378 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Protein’s Functions in the Body 383 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Diseases Involving Proteins 395 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Proteins in a Nutshell 405 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Proteins, Diet, and Personal Choices 409 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part VII. Chapter 7. Alcohol Introduction 431 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Alcohol Metabolism 436 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Health Consequences of Alcohol Abuse 442 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Health Benefits of Moderate Alcohol Intake 448 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part VIII. Chapter 8. Energy Introduction 453 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Atom 460 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Weight Management 472 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Factors Affecting Energy Intake 485 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Factors Affecting Energy Expenditure 492 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Dietary, Behavioral, and Physical Activity 501 Recommendations for Weight Management University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part IX. Chapter 9. Vitamins Introduction 515 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Fat-Soluble Vitamins 521 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Water-Soluble Vitamins 550 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Antioxidants 593 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Body’s Offense 597 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Phytochemicals 600 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part X. Chapter 10. Major Minerals Introduction 609 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Calcium 613 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Phosphorus 631 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Sulfur 635 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Magnesium 640 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Summary of Major Minerals 645 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XI. Chapter 11. Trace Minerals Introduction 651 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Iron 655 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Copper 666 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Zinc 671 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Selenium 675 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Iodine 681 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Chromium 686 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Manganese 689 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Molybdenum 692 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Fluoride 695 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Summary of Trace Minerals 700 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XII. Chapter 12. Nutrition Applications Introduction 707 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Understanding Dietary Reference Intakes 710 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Discovering Nutrition Facts 718 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Building Healthy Eating Patterns 740 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program MyPlate Planner 745 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Pacific Based Dietary Guidelines 760 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Understanding the Bigger Picture of Dietary 768 Guidelines University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XIII. Chapter 13. Lifespan Nutrition From Pregnancy to the Toddler Years Introduction 779 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Pregnancy 785 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Infancy 807 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Toddler Years 852 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XIV. Chapter 14. Lifespan Nutrition During Childhood and Adolescence Introduction 867 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Childhood 871 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Adolescence 884 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Late Adolescence 889 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XV. Chapter 15. Lifespan Nutrition in Adulthood Introduction 903 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Young Adulthood 907 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Middle Age 913 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Older Adulthood: The Golden Years 919 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XVI. Chapter 16. Performance Nutrition Introduction 933 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Essential Elements of Physical Fitness 936 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Benefits of Physical Activity 945 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Fuel Sources 950 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Sports Nutrition 959 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Water and Electrolyte Needs 972 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Food Supplements and Food Replacements 977 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XVII. Chapter 17. Food Safety Introduction 987 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Major Types of Foodborne Illness 992 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Causes of Food Contamination 997 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Protecting the Public Health 1011 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Food System 1017 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Food Preservation 1019 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Food Processing 1025 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program The Effect of New Technologies 1030 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Efforts on the Consumer Level: What You Can Do 1034 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program  Part XVIII. Chapter 18. Nutritional Issues Introduction 1043 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Comparing Diets 1046 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program 1. Calories In Versus Calories Out 1063 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Nutrition, Health and Disease 1076 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Threats to Health 1098 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Undernutrition, Overnutrition, and Malnutrition 1121 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Food Insecurity 1132 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Careers in Nutrition 1143 University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Part XIX. Appendices Appendix A 1151 Appendix A University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Appendix B 1156 Attributions University of Hawai‘i at Mānoa Food Science and Human Nutrition Program and Human Nutrition Program Preface UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM ‘A‘ohe pau ka ‘ike i ka hālau ho‘okahi Knowledge isn’t taught in all one place This open access textbook was developed as an introductory nutrition resource to reflect the diverse dietary patterns of people in Hawai‘i and the greater Pacific. Using the ‘ōlelo no‘eau, or Hawaiian proverb, stated above, we believe that the principles of nutrition should be taught through the context of our communities and environments. Its intended audience are students from the University of Hawai‘i at Mānoa enrolled in the Food Science and Human Nutrition (FSHN) 185 course, The Science of Human Nutrition. However, this open access textbook may be of interest to other courses interested in teaching nutrition through a Hawai‘i- Pacific framed lens. This book is best viewed online using the pressbooks format however, multiple formats (e.g., pdf, epub, mobi) are also made available. Preface | xxv About the Contributors UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM This open access textbook was made possible through the collaboration of faculty, students and staff at the University of Hawai‘i at Mānoa demonstrating the value of working together, ho‘okahi ka ‘ilau like ana. Faculty Jennifer Draper xxvi | About the Contributors  Jennifer Draper is a Lecturer in the Department of Human Nutrition, Food and Animal Sciences. She received her MA in Nutrition Science from the University of Texas at Austin. She is a Registered Dietitian in private practice specializing in eating disorders and emotional over-eating. She enjoys interacting with students and is passionate about helping people have a healthy relationship with food and their bodies. Marie Kainoa Fialkowski Revilla Marie Kainoa Fialkowski Revilla is a Native Hawaiian faculty member in the Department of Human Nutrition, Food, and Animal Sciences at the University of Hawai‘i at Mānoa. She teaches a number of courses in nutrition both face to face and online. She is dedicated to developing readily available and accessible nutrition education materials and curricula that reflect Hawai‘i and the Pacific to ensure that her students can relate to the content being learned. She enjoys spending time with her ‘ohana (family) at their home in Ahuimanu on the island of O‘ahu. About the Contributors | xxvii Alan Titchenal Dr. Titchenal received a PhD in nutrition from the University of California at Davis with emphasis on exercise physiology and physiological chemistry. His work at the University of Hawai‘i at Mānoa has focused on the broad areas of nutrition and human performance and translation of nutrition science for public consumption. This has included the “Got Nutrients?” project that provides daily messages on topics related to nutrition, fitness, and health and the publication of over 600 articles in the Honolulu Star- Advertiser newspaper. xxviii | About the Contributors Students Noemi Arceo Caacbay Noemi Arceo Caacbay is a Masters Student in the Public Health, Health Policy and Management Program at the University of Hawai‘i at Mānoa. She enjoys learning about all things health-science related. She is passionate about returning to her home of Saipan, CNMI where she will give back and serve her community. About the Contributors | xxix Allison Calabrese Allison Calabrese is currently a MS graduate student in the Nutritional Sciences Program at University of Hawai‘i at Mānoa. She obtained her BS from California Lutheran University in Exercise Science with an emphasis in Health Professions. Her research interests include the relationship between diet and optimal health. xxx | About the Contributors Chynna Nicole Chun Chynna Chun is an undergraduate student majoring in Tropical Agriculture and the Environment (TAE) with a specialty in plant production and management at the University of Hawai‘i at Mānoa. She also serves as a student assistant at the CTAHR Academic and Student Affairs Office (ASAO) and the 2019-2020 Future Farmers of America Hawai‘i State Treasurer. About the Contributors | xxxi Cheryl Gibby Cheryl Gibby was born and raised in Hawai‘i and is a wife and mother of three. She received her BA, MS in Nutritional Sciences, and PhD in Nutrition from the University of Hawai‘i at Mānoa. She has served as an instructor for the introductory Nutrition course at the University of Hawai‘i at Mānoa, and her research interests include infant and child health, dental and bone health, mobile health interventions, school nutrition policies, and online education. xxxii | About the Contributors Skylar Hara Skylar Hara is an undergraduate student student in the Tropical Agriculture and the Environment program at the University of Hawai‘i at Mānoa. She has a growing love for plants and hopes to go to graduate school to conduct research in the future. About the Contributors | xxxiii Gemady Langfelder Gemady Langfelder is an undergraduate dietetics student at the University of Hawai‘i at Mānoa. She is an ACSM certified personal trainer and a novice horticulturist. Her interests are nutritional epidemiology, infant and pre-/post-natal nutrition, and health policy. xxxiv | About the Contributors Ya-Yun Yang Ya-Yun is a Graduate Assistant in the Distance Education Program for the College of Tropical Agriculture and Human Resources. She is currently a PhD student in Learning Design and Technology (LTEC) at the University of Hawai‘i at Mānoa. Christina Gar Lai Young About the Contributors | xxxv  Christina Gar Lai Young is currently an undergraduate student in Dietetics at the College of Tropical Agriculture and Human Resources at the University of Hawaiʻi at Mānoa. She plans to become a Registered Dietitian after obtaining her undergraduate degree and completing her supervised practice in dietetics. Staff Ty Lim Ty Lim is an instructional designer who received his MA in Education and BA in Anthropology. He is excited about helping to create open educational resources for FSHN and CTAHR. xxxvi | About the Contributors Billy Meinke Billy is the Open Educational Resources Technologist for the Outreach College at the University of Hawai‘i at Mānoa. About the Contributors | xxxvii Kellie Taguchi Kellie is the Distance Education Coordinator for the College of Tropical Agriculture and Human Resources at the University of Hawai‘i at Mānoa. Contact Person Dr. Marie Kainoa Fialkowski Revilla [email protected] 808-956-8337 1955 East West Road Honolulu, HI 96822 University of Hawaii at Manoa Department of Human Nutrition, Food, and Animal Sciences xxxviii | About the Contributors Note to Educators Using this Resource Please send edits and suggestions directly to Dr. Fialkowski Revilla on how we may improve the textbook. We also welcome others to adopt the book for their own course needs, however, we would like to be able to keep a record of users so that we may update them on any critical changes to the textbook. Please contact Dr. Fialkowski Revilla if you are considering to adopt the textbook for your course. About the Contributors | xxxix Acknowledgements UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM This Open Educational Resource textbook has been adapted from: OpenStax Anatomy and Physiology // CC BY 4.0 Chapter 2 The Human Body An Introduction to Human Nutrition // CC BY-NC-SA 3.0 Chapter 1 Basic Concepts in Nutrition Chapter 3 Water and Electrolytes Chapter 4 Carbohydrates Chapter 5 Lipids Chapter 6 Protein Chapter 8 Energy Chapter 12 Nutrition Applications Chapter 13 Lifespan Nutrition From Pregnancy to the Toddler Years Chapter 14 Lifespan Nutrition During Childhood and Adolescence Chapter 15 Lifespan Nutrition in Adulthood Chapter 17 Food Safety Chapter 18 Nutritional Issues Chapters and sections were borrowed and adapted from the above existing OER textbooks on human nutrition. Without these foundational texts, a lot more work would have been required to complete this project. Mahalo (thank you) to those who shared before us. All other content should include the following attribution statement: — xl | Acknowledgements  This work is licensed under a Creative Commons Attribution 4.0 International License. Human Nutrition by the University of Hawai’i at Mānoa Food Science and Human Nutrition Program. Download this book for free at: http://pressbooks.oer.hawaii.edu/ humannutrition/ — This Open Educational Resource textbook was also inspired by: Kansas State University Human Nutrition | goo.gl/vOAnR // CC BY 3.0 Edited and Reviewed by Carolyn Donohoe-Mather – University of Hawai’i at Mānoa, Chapter reviewer Cecille Farnum — Ryerson University, Copyeditor Changqi Leu — San Diego State University, Chapter reviewer Billy Meinke — University of Hawai’i at Mānoa, Project manager Paula Parslow — Private, Copyeditor Trina Robertson — Saddleback College, Chapter reviewer Allison Tepper — American University, Chapter reviewer Front Cover Photo Noa Kekuewa Lincoln / CC BY 4.0 Acknowledgements | xli Special Thanks to Bill Chismar – University of Hawai’i at Mānoa, Dean of Outreach College The Children’s Healthy Living Summer Institute – University of Hawai’i at Mānoa Open Educational Resources This text is provided to you as an Open Educational Resource (OER) which you access online. It is designed to give you a comprehensive introduction to human nutrition at no or very nominal cost. It contains both written and graphic text material, intra-text links to other internal material which may aid in understanding topics and concepts, intra-text links to the appendices and glossary for tables and definitions of words, and extra-text links to videos and web material that clarifies and augments topics and concepts. xlii | Acknowledgements PART I CHAPTER 1. BASIC CONCEPTS IN NUTRITION Chapter 1. Basic Concepts in Nutrition | 1 Introduction UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM ʻO ke kahua ma mua, ma hope ke kūkulu The foundation comes first, then the building Image by Jim Hollyer / CC BY 4.0 Introduction | 3  Learning Objectives By the end of this chapter, you will be able to: Describe basic concepts in nutrition Describe factors that affect your nutritional needs Describe the importance of research and scientific methods to understanding nutrition What are Nutrients? The foods we eat contain nutrients. Nutrients are substances required by the body to perform its basic functions. Nutrients must be obtained from our diet, since the human body does not synthesize or produce them. Nutrients have one or more of three basic functions: they provide energy, contribute to body structure, and/or regulate chemical processes in the body. These basic functions allow us to detect and respond to environmental surroundings, move, excrete wastes, respire (breathe), grow, and reproduce. There are six classes of nutrients required for the body to function and maintain overall health. These are carbohydrates, lipids, proteins, water, vitamins, and minerals. Foods also contain non-nutrients that may be harmful (such as natural toxins common in plant foods and additives like some dyes and preservatives) or beneficial (such as antioxidants). 4 | Introduction Macronutrients Nutrients that are needed in large amounts are called macronutrients. There are three classes of macronutrients: carbohydrates, lipids, and proteins. These can be metabolically processed into cellular energy. The energy from macronutrients comes from their chemical bonds. This chemical energy is converted into cellular energy that is then utilized to perform work, allowing our bodies to conduct their basic functions. A unit of measurement of food energy is the calorie. On nutrition food labels the amount given for “calories” is actually equivalent to each calorie multiplied by one thousand. A kilocalorie (one thousand calories, denoted with a small “c”) is synonymous with the “Calorie” (with a capital “C”) on nutrition food labels. Water is also a macronutrient in the sense that you require a large amount of it, but unlike the other macronutrients, it does not yield calories. Carbohydrates Carbohydrates are molecules composed of carbon, hydrogen, and oxygen. The major food sources of carbohydrates are grains, milk, fruits, and starchy vegetables, like potatoes. Non-starchy vegetables also contain carbohydrates, but in lesser quantities. Carbohydrates are broadly classified into two forms based on their chemical structure: simple carbohydrates, often called simple sugars; and complex carbohydrates. Simple carbohydrates consist of one or two basic units. Examples of simple sugars include sucrose, the type of sugar you would have in a bowl on the breakfast table, and glucose, the type of sugar that circulates in your blood. Complex carbohydrates are long chains of simple sugars that can be unbranched or branched. During digestion, the body breaks Introduction | 5 down digestible complex carbohydrates to simple sugars, mostly glucose. Glucose is then transported to all our cells where it is stored, used to make energy, or used to build macromolecules. Fiber is also a complex carbohydrate, but it cannot be broken down by digestive enzymes in the human intestine. As a result, it passes through the digestive tract undigested unless the bacteria that inhabit the colon or large intestine break it down. One gram of digestible carbohydrates yields four kilocalories of energy for the cells in the body to perform work. In addition to providing energy and serving as building blocks for bigger macromolecules, carbohydrates are essential for proper functioning of the nervous system, heart, and kidneys. As mentioned, glucose can be stored in the body for future use. In humans, the storage molecule of carbohydrates is called glycogen, and in plants, it is known as starch. Glycogen and starch are complex carbohydrates. Lipids Lipids are also a family of molecules composed of carbon, hydrogen, and oxygen, but unlike carbohydrates, they are insoluble in water. Lipids are found predominantly in butter, oils, meats, dairy products, nuts, and seeds, and in many processed foods. The three main types of lipids are triglycerides (triacylglycerols), phospholipids, and sterols. The main job of lipids is to provide or store energy. Lipids provide more energy per gram than carbohydrates (nine kilocalories per gram of lipids versus four kilocalories per gram of carbohydrates). In addition to energy storage, lipids serve as a major component of cell membranes, surround and protect organs (in fat-storing tissues), provide insulation to aid in temperature regulation, and regulate many other functions in the body. 6 | Introduction Proteins Proteins are macromolecules composed of chains of subunits called amino acids. Amino acids are simple subunits composed of carbon, oxygen, hydrogen, and nitrogen. Food sources of proteins include meats, dairy products, seafood, and a variety of different plant- based foods, most notably soy. The word protein comes from a Greek word meaning “of primary importance,” which is an apt description of these macronutrients; they are also known colloquially as the “workhorses” of life. Proteins provide four kilocalories of energy per gram; however providing energy is not protein’s most important function. Proteins provide structure to bones, muscles and skin, and play a role in conducting most of the chemical reactions that take place in the body. Scientists estimate that greater than one-hundred thousand different proteins exist within the human body. The genetic codes in DNA are basically protein recipes that determine the order in which 20 different amino acids are bound together to make thousands of specific proteins. Figure 1.1 The Macronutrients: Carbohydrates, Lipids, Protein, and Water Figure 1.1 The Macronutrie nts: Carbohydrat es, Lipids, Protein, and Water Introduction | 7 Water There is one other nutrient that we must have in large quantities: water. Water does not contain carbon, but is composed of two hydrogens and one oxygen per molecule of water. More than 60 percent of your total body weight is water. Without it, nothing could be transported in or out of the body, chemical reactions would not occur, organs would not be cushioned, and body temperature would fluctuate widely. On average, an adult consumes just over two liters of water per day from food and drink combined. Since water is so critical for life’s basic processes, the amount of water input and output is supremely important, a topic we will explore in detail in Chapter 4. Micronutrients Micronutrients are nutrients required by the body in lesser amounts, but are still essential for carrying out bodily functions. Micronutrients include all the essential minerals and vitamins. There are sixteen essential minerals and thirteen vitamins (See Table 1.1 “Minerals and Their Major Functions” and Table 1.2 “Vitamins and Their Major Functions” for a complete list and their major functions). In contrast to carbohydrates, lipids, and proteins, micronutrients are not sources of energy (calories), but they assist in the process as cofactors or components of enzymes (i.e., coenzymes). Enzymes are proteins that catalyze chemical reactions in the body and are involved in all aspects of body functions from producing energy, to digesting nutrients, to building macromolecules. Micronutrients play many essential roles in the body. Table 1.1 Minerals and Their Major Functions 8 | Introduction Minerals Major Functions Macro Sodium Fluid balance, nerve transmission, muscle contraction Chloride Fluid balance, stomach acid production Potassium Fluid balance, nerve transmission, muscle contraction Bone and teeth health maintenance, nerve transmission, Calcium muscle contraction, blood clotting Phosphorus Bone and teeth health maintenance, acid-base balance Protein production, nerve transmission, muscle Magnesium contraction Sulfur Protein production Trace Iron Carries oxygen, assists in energy production Protein and DNA production, wound healing, growth, Zinc immune system function Iodine Thyroid hormone production, growth, metabolism Selenium Antioxidant Copper Coenzyme, iron metabolism Manganese Coenzyme Bone and teeth health maintenance, tooth decay Fluoride prevention Chromium Assists insulin in glucose metabolism Molybdenum Coenzyme Minerals Minerals are solid inorganic substances that form crystals and are classified depending on how much of them we need. Trace minerals, such as molybdenum, selenium, zinc, iron, and iodine, are only required in a few milligrams or less. Macrominerals, such as calcium, magnesium, potassium, sodium, and phosphorus, are required in hundreds of milligrams. Many minerals are critical for enzyme Introduction | 9 function, others are used to maintain fluid balance, build bone tissue, synthesize hormones, transmit nerve impulses, contract and relax muscles, and protect against harmful free radicals in the body that can cause health problems such as cancer. Vitamins The thirteen vitamins are categorized as either water-soluble or fat-soluble. The water-soluble vitamins are vitamin C and all the B vitamins, which include thiamine, riboflavin, niacin, pantothenic acid, pyridoxine, biotin, folate and cobalamin. The fat-soluble vitamins are A, D, E, and K. Vitamins are required to perform many functions in the body such as making red blood cells, synthesizing bone tissue, and playing a role in normal vision, nervous system function, and immune system function. Table 1.2 Vitamins and Their Major Functions 10 | Introduction Vitamins Major Functions Water-soluble Thiamin (B1) Coenzyme, energy metabolism assistance Riboflavin (B2 ) Coenzyme, energy metabolism assistance Niacin (B3) Coenzyme, energy metabolism assistance Pantothenic acid Coenzyme, energy metabolism assistance (B5) Pyridoxine (B6) Coenzyme, amino acid synthesis assistance Biotin (B7) Coenzyme, amino acid and fatty acid metabolism Folate (B9) Coenzyme, essential for growth Cobalamin (B12) Coenzyme, red blood cell synthesis C (ascorbic acid) Collagen synthesis, antioxidant Fat-soluble A Vision, reproduction, immune system function Bone and teeth health maintenance, immune system D function E Antioxidant, cell membrane protection K Bone and teeth health maintenance, blood clotting Vitamin deficiencies can cause severe health problems and even death. For example, a deficiency in niacin causes a disease called pellagra, which was common in the early twentieth century in some parts of America. The common signs and symptoms of pellagra are known as the “4D’s—diarrhea, dermatitis, dementia, and death.” Until scientists found out that better diets relieved the signs and symptoms of pellagra, many people with the disease ended up hospitalized in insane asylums awaiting death. Other vitamins were also found to prevent certain disorders and diseases such as scurvy (vitamin C), night blindness vitamin A, and rickets (vitamin D). Table 1.3 Functions of Nutrients Introduction | 11  Necessary for tissue formation, cell reparation, and Protein hormone and enzyme production. It is essential for building strong muscles and a healthy immune system. Provide a ready source of energy for the body and Carbohydrates provide structural constituents for the formation of cells. Provides stored energy for the body, functions as structural components of cells and also as signaling Fat molecules for proper cellular communication. It provides insulation to vital organs and works to maintain body temperature. Regulate body processes and promote normal Vitamins body-system functions. Regulate body processes, are necessary for proper Minerals cellular function, and comprise body tissue. Transports essential nutrients to all body parts, Water transports waste products for disposal, and aids with body temperature maintenance. Learning Activities Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are available in the web-based textbook and not available in the downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document). Learning activities may be used across various mobile devices, however, for the best user experience it is strongly 12 | Introduction recommended that users complete these activities using a desktop or laptop computer and in Google Chrome. An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=46 An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=46 Introduction | 13 Food Quality UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM Image by David De Veroli on unsplash.co m / CC0 One measurement of food quality is the amount of nutrients it contains relative to the amount of energy it provides. High-quality foods are nutrient-dense, meaning they contain significant amounts of one or more essential nutrients relative to the amount of calories they provide. Nutrient-dense foods are the opposite of “empty- calorie” foods such as carbonated sugary soft drinks, which provide many calories and very little, if any, other nutrients. Food quality is additionally associated with its taste, texture, appearance, microbial content, and how much consumers like it. Food: A Better Source of Nutrients It is better to get all your micronutrients from the foods you eat as opposed to from supplements. Supplements contain only what is 14 | Food Quality listed on the label, but foods contain many more macronutrients, micronutrients, and other chemicals, like antioxidants, that benefit health. While vitamins, multivitamins, and supplements are a $20 billion industry in the United States, and more than 50 percent of Americans purchase and use them daily, there is no consistent evidence that they are better than food in promoting health and preventing disease. Everyday Connection Make a list of some of your favorite foods and visit the “What’s In the Foods You Eat?” search tool provided by the USDA. What are some of the nutrients found in your favorite foods? Food Quality | 15  USDA https://ww w.ars.usda. gov/ northeast- area/ beltsville- md-bhnrc/ beltsville-h uman-nutr ition-resea rch-center / food-surve ys-researc h-group/ docs/ whats-in-t he-foods-y ou-eat-ems earch-toole m/ Learning Activities Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are available in the web-based textbook and not available in the 16 | Food Quality downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document). Learning activities may be used across various mobile devices, however, for the best user experience it is strongly recommended that users complete these activities using a desktop or laptop computer and in Google Chrome. An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=50 Food Quality | 17 Units of Measure UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM In nutrition, there are two systems of commonly used measurements: Metric and US Customary. We need both because the US won’t adopt the metric system completely. The Metric and US Customary System These are commonly used prefixes for the Metric System: Micro- (μ) 1/1,000,000th (one millionth) Milli- (m) 1/1000th (one thousandth) Centi- (c) 1/100th (one hundredth) Deci- (d) 1/10th (one tenth) Kilo- (k) 1000x (one thousand times) Mass Metric System US Customary System Conversions Microgram (μg) Ounce (oz) 1 oz = 28.35 g Milligram (mg) Pound (lb) 1 lb = 16 oz Gram (g) 1 lb = 454 g Kilogram (kg) 1 kg = 2.2 lbs 18 | Units of Measure Volume Metric System US Customary System Conversions Milliliter (mL) Teaspoon (tsp) 1 tsp = 5 mL Deciliter (dL) Tablespoon (tbsp) 1 tbsp = 3 tsp = 15 mL Liter (L) Fluid ounce (fl oz) 1 fl oz = 2 tbsp = 30 mL Cup (c) 1 c = 8 fl oz = 237 mL Pint (pt) 1 pt = 2 c = 16 fl oz Quart (qt) 1 qt = 4 c = 32 fl oz = 0.95 L Gallon (gal) = 4 qt 1 gal = 4 qt Length Metric System US Customary System Conversions Millimeter (mm) Inch (in) 1 in = 25.4 mm Centimeter (cm) Foot (ft) 1 ft= 30.5 cm Meter (m) Yard (yd) 1 yd = 0.9 m Kilometer (km) Mile (mi) 1 mi = 1.6 km Learning Activities Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are Units of Measure | 19  available in the web-based textbook and not available in the downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document). Learning activities may be used across various mobile devices, however, for the best user experience it is strongly recommended that users complete these activities using a desktop or laptop computer and in Google Chrome. An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=52 20 | Units of Measure Lifestyles and Nutrition UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM Image by John Towner on unsplash.co m / CC0 In addition to nutrition, health is affected by genetics, the environment, life cycle, and lifestyle. One facet of lifestyle is your dietary habits. Recall that we discussed briefly how nutrition affects health. A greater discussion of this will follow in subsequent chapters in this book, as there is an enormous amount of information regarding this aspect of lifestyle. Dietary habits include what a person eats, how much a person eats during a meal, how frequently meals are consumed, and how often a person eats out. Other aspects of lifestyle include physical activity level, recreational drug use, and sleeping patterns, all of which play a role in health and impact nutrition. Following a healthy lifestyle improves your overall health. Lifestyles and Nutrition | 21  Physical Activity In 2008, the Health and Human Services (HHS) released the Physical 1 Activity Guidelines for Americans. The HHS states that “Being physically active is one of the most important steps that Americans of all ages can take to improve their health. The 2008 Physical Activity Guidelines for Americans provides science-based guidance to help Americans aged six and older improve their health through appropriate physical activity.” The guidelines recommend exercise programs for people in many different stages of their lifecycle. The HHS reports that there is strong evidence that increased physical activity decreases the risk of early death, heart disease, stroke, Type 2 diabetes, high blood pressure, and certain cancers; prevents weight gain and falls; and improves cognitive function in the elderly. These guidelines are scheduled for an update in 2018. Also unveiled recently are the Canadian Physical Activity Guidelines, which are available at the website of The Canadian Society for Exercise 2 Physiology. Recreational Drug Use Recreational drug use, which includes tobacco-smoking, electronic smoking device use, and alcohol consumption along with narcotic and other illegal drug use, has a large impact on health. Smoking 1. U.S. Department of Health and Human Services' Office of Disease Prevention and Health Promotion. Physical Activity. https://health.gov/paguidelines/ 2. Canadian Society for Exercise Physiology. http://www.csep.ca/english/view.asp?x=804 22 | Lifestyles and Nutrition  cigarettes can cause lung cancer, eleven other types of cancer, heart disease, and several other disorders or diseases that markedly decrease quality of life and increase mortality. In the United States, smoking causes more than four hundred thousand deaths every single year, which is far more than deaths associated with any other 3 lifestyle component. Also, according to the Centers for Disease Control and Prevention (CDC), excessive alcohol intake causes an estimated seventy-five 4 thousand deaths per year. Staying away from excessive alcohol intake lowers blood pressure, the risk from injury, heart disease, stroke, liver problems, and some types of cancer. While excessive alcohol consumption can be linked to poor health, consuming alcohol in moderation has been found to promote health such as reducing the risk for heart disease and Type 2 diabetes in some people. The United States Department of Health and Human Services (HHS) defines drinking in moderation as no more than one 5 drink a day for women and two drinks a day for men. Illicit and prescription drug abuse are associated with decreased health and is a prominent problem in the United States. The health 3. Centers for Disease Control and Prevention (2020, April 28). Tobacco and Mortality. http://www.cdc.gov/ tobacco/data_statistics/fact_sheets/health_effects/ tobacco_related_mortality/Index.htm. 4. Centers for Disease Control and Prevention (2020, January 3). Underage Drinking. http://www.cdc.gov/ healthyyouth/alcoholdrug/ 5. U.S. Department of Health and Human Services and U.S. Department of Agriculture (2015, December). 2015 – 2020 Dietary Guidelines for Americans. 8th Edition. https://health.gov/our-work/food-nutrition/ 2015-2020-dietary-guidelines/guidelines/ Lifestyles and Nutrition | 23  effects of drug abuse can be far-reaching, including the increased 6 risk of stroke, heart disease, cancer, lung disease, and liver disease. Sleeping Patterns Inadequate amounts of sleep, or not sleeping well, can also have remarkable effects on a person’s health. In fact, sleeping can affect your health just as much as your diet. Scientific studies have shown that insufficient sleep increases the risk for heart disease, Type 2 diabetes, obesity, and depression. Abnormal breathing during sleep, a condition called sleep apnea, is also linked to an increased risk for 7 chronic disease. Personal Choice: The Challenge of Choosing Foods There are other factors besides environment and lifestyle that influence the foods you choose to eat. Different foods affect energy level, mood, how much is eaten, how long before you eat again, and if cravings are satisfied. We have talked about some of the physical effects of food on your body, but there are other effects too. Food regulates your appetite and how you feel. Multiple studies 6. National Institute on Drug Abuse (2017, March 23). Health Consequences of Drug Misuse. https://www.drugabuse.gov/related-topics/health- consequences-drug-misuse. 7. National Sleep Foundation. Sleep Disorders. https://sleepfoundation.org/sleep-disorders-problems 24 | Lifestyles and Nutrition have demonstrated that some high fiber foods and high-protein foods decrease appetite by slowing the digestive process and prolonging the feeling of being full or satiety. The effects of individual foods and nutrients on mood are not backed by consistent scientific evidence, but in general, most studies support that healthier diets are associated with a decrease in depression and improved well-being. To date, science has not been able to track the exact path in the brain that occurs in response to eating a particular food, but it is quite clear that foods, in general, stimulate emotional responses in people. Food also has psychological, cultural, and religious significance, so your personal choices of food affect your mind, as well as your body. The social implications of food have a great deal to do with what people eat, as well as how and when. Special events in individual lives—from birthdays to funerals—are commemorated with equally special foods. Being aware of these forces can help people make healthier food choices—and still honor the traditions and ties they hold dear. Typically, eating kosher food means a person is Jewish; eating fish on Fridays during Lent means a person is Catholic; fasting during the ninth month of the Islamic calendar means a person is Muslim. On New Year’s Day, Japanese take part in an annual tradition of Mochitsuki also known as Mochi pounding in hopes of gaining good fortune over the coming year. Several hundred miles away in Hawai‘i, people eat poi made from pounded taro root with great significance in the Hawaiian culture, as it represents Hāloa, the ancestor of chiefs and kanaka maoli (Native Hawaiians). National food traditions are carried to other countries when people immigrate. The local cuisine in Hawai‘i would not be what it is today without the contributions of Japanese, Chinese, European, and other immigrant communities. Lifestyles and Nutrition | 25 Factors that Drive Food Choices Along with these influences, a number of other factors affect the dietary choices individuals make, including: Taste, texture, and appearance. Individuals have a wide range of tastes which influence their food choices, leading some to dislike milk and others to hate raw vegetables. Some foods that are very healthy, such as tofu, may be unappealing at first to many people. However, creative cooks can adapt healthy foods to meet most people’s taste. Economics. Access to fresh fruits and vegetables may be scant, particularly for those who live in economically disadvantaged or remote areas, where cheaper food options are limited to convenience stores and fast food. Early food experiences. People who were not exposed to different foods as children, or who were forced to swallow every last bite of overcooked vegetables, may make limited food choices as adults. Habits. It’s common to establish eating routines, which can work both for and against optimal health. Habitually grabbing a fast food sandwich for breakfast can seem convenient, but might not offer substantial nutrition. Yet getting in the habit of drinking an ample amount of water each day can yield multiple benefits. Culture. The culture in which one grows up affects how one sees food in daily life and on special occasions. Geography. Where a person lives influences food choices. For instance, people who live in Midwestern US states have less access to seafood than those living along the coasts. Advertising. The media greatly influences food choice by persuading consumers to eat certain foods. Social factors. Any school lunchroom observer can testify to the impact of peer pressure on eating habits, and this 26 | Lifestyles and Nutrition  influence lasts through adulthood. People make food choices based on how they see others and want others to see them. For example, individuals who are surrounded by others who consume fast food are more likely to do the same. Health concerns. Some people have significant food allergies, to peanuts for example, and need to avoid those foods. Others may have developed health issues which require them to follow a low salt diet. In addition, people who have never worried about their weight have a very different approach to eating than those who have long struggled with excess weight. Emotions. There is a wide range in how emotional issues affect eating habits. When faced with a great deal of stress, some people tend to overeat, while others find it hard to eat at all. Green food/Sustainability choices. Based on a growing understanding of diet as a public and personal issue, more and more people are starting to make food choices based on their environmental impact. Realizing that their food choices help shape the world, many individuals are opting for a vegetarian diet, or, if they do eat animal products, striving to find the most “cruelty-free” options possible. Purchasing local and organic food products and items grown through sustainable processes also helps shrink the size of one’s dietary footprint. People choose a vegetarian diet for various reasons, including religious doctrines, health concerns, ecological and animal welfare concerns, or simply because they dislike the taste of meat. There are different types of vegetarians, but a common theme is that vegetarians do not eat meat. Four common forms of vegetarianism are: 1. Lacto-ovo vegetarian. This is the most common form. This type of vegetarian diet includes the animal foods eggs and dairy products. 2. Lacto-vegetarian. This type of vegetarian diet includes dairy products but not eggs. Lifestyles and Nutrition | 27 3. Ovo-vegetarian. This type of vegetarian diet includes eggs but not dairy products. 4. Vegan. This type of vegetarian diet does not include dairy, eggs, or any type of animal product or animal by-product. Learning Activities Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are available in the web-based textbook and not available in the downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document). Learning activities may be used across various mobile devices, however, for the best user experience it is strongly recommended that users complete these activities using a desktop or laptop computer and in Google Chrome. An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=55 28 | Lifestyles and Nutrition  An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=55 Lifestyles and Nutrition | 29 Achieving a Healthy Diet UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM Achieving a healthy diet is a matter of balancing the quality and quantity of food that is eaten. There are five key factors that make up a healthful diet: 1. A diet must be adequate, by providing sufficient amounts of each essential nutrient, as well as fiber and adequate calories. 2. A balanced diet results when you do not consume one nutrient at the expense of another, but rather get appropriate amounts of all nutrients. 3. Calorie control is necessary so that the amount of energy you get from the nutrients you consume equals the amount of energy you expend during your day’s activities. 4. Moderation means not eating to the extremes, neither too much nor too little. 5. Variety refers to consuming different foods from within each of the food groups on a regular basis. A healthy diet is one that favors whole foods. As an alternative to modern processed foods, a healthy diet focuses on “real” fresh whole foods that have been sustaining people for generations. Whole foods supply the needed vitamins, minerals, protein, carbohydrates, fats, and fiber that are essential to good health. Commercially prepared and fast foods are often lacking nutrients and often contain inordinate amounts of sugar, salt, saturated and trans fats, all of which are associated with the development of diseases such as atherosclerosis, heart disease, stroke, cancer, obesity, diabetes, and other illnesses. A balanced diet is a mix of food from the different food groups (vegetables, legumes, fruits, grains, protein foods, and dairy). 30 | Achieving a Healthy Diet Adequacy An adequate diet is one that favors nutrient-dense foods. Nutrient- dense foods are defined as foods that contain many essential nutrients per calorie. Nutrient-dense foods are the opposite of “empty-calorie” foods, such as sugary carbonated beverages, which are also called “nutrient-poor.” Nutrient-dense foods include fruits and vegetables, lean meats, poultry, fish, low-fat dairy products, and whole grains. Choosing more nutrient-dense foods will facilitate weight loss, while simultaneously providing all necessary nutrients. Balance Balance the foods in your diet. Achieving balance in your diet entails not consuming one nutrient at the expense of another. For example, calcium is essential for healthy teeth and bones, but too much calcium will interfere with iron absorption. Most foods that are good sources of iron are poor sources of calcium, so in order to get the necessary amounts of calcium and iron from your diet, a proper balance between food choices is critical. Another example is that while sodium is an essential nutrient, excessive intake may contribute to congestive heart failure and chronic kidney disease in some people. Remember, everything must be consumed in the proper amounts. Moderation Eat in moderation. Moderation is crucial for optimal health and survival. Eating nutrient-poor foods each night for dinner will lead to health complications. But as part of an otherwise healthful diet and consumed only on a weekly basis, this should not significantly Achieving a Healthy Diet | 31 impact overall health. It’s important to remember that eating is, in part, about enjoyment and indulging with a spirit of moderation. This fits within a healthy diet. Monitor food portions. For optimum weight maintenance, it is important to ensure that energy consumed from foods meets the energy expenditures required for body functions and activity. If not, the excess energy contributes to gradual, steady accumulation of stored body fat and weight gain. In order to lose body fat, you need to ensure that more calories are burned than consumed. Likewise, in order to gain weight, calories must be eaten in excess of what is expended daily. Variety Variety involves eating different foods from all the food groups. Eating a varied diet helps to ensure that you consume and absorb adequate amounts of all essential nutrients required for health. One of the major drawbacks of a monotonous diet is the risk of consuming too much of some nutrients and not enough of others. Trying new foods can also be a source of pleasure—you never know what foods you might like until you try them. Developing a healthful diet can be rewarding, but be mindful that all of the principles presented must be followed to derive maximal health benefits. For instance, introducing variety in your diet can still result in the consumption of too many high-calorie, nutrient poor foods and inadequate nutrient intake if you do not also employ moderation and calorie control. Using all of these principles together will promote lasting health benefits. 32 | Achieving a Healthy Diet  Learning Activities Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are available in the web-based textbook and not available in the downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document). Learning activities may be used across various mobile devices, however, for the best user experience it is strongly recommended that users complete these activities using a desktop or laptop computer and in Google Chrome. An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=57 Achieving a Healthy Diet | 33 Research and the Scientific Method UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM ask more questions signage https://www.peakpx.com /519652/ ask-more-qu estions-sign age Nutritional scientists discover the health effects of food and its nutrients by first making an observation. Once observations are made, they come up with a hypothesis, test their hypothesis, and then interpret the results. After this, they gather additional evidence from multiple sources and finally come up with a conclusion. This organized process of inquiry used in science is called the scientific method. 34 | Research and the Scientific Method  Figure 1.2 Scientific Method Steps Scientific Method steps In 1811, French chemist Bernard Courtois was isolating saltpeter for producing gunpowder to be used by Napoleon’s army. To carry out this isolation, he burned some seaweed and in the process, observed an intense violet vapor that crystallized when he exposed it to a cold surface. He sent the violet crystals to an expert on gases, Joseph Gay-Lussac, who identified the crystal as a new element. It was named iodine, the Greek word for violet. The following scientific record is some of what took place in order to conclude that iodine is a nutrient. Observation. Eating seaweed is a cure for goiter, a gross enlargement of the thyroid gland in the neck. Hypothesis. In 1813, Swiss physician Jean-Francois Coindet hypothesized that the seaweed contained iodine, and that iodine 1 could be used instead of seaweed to treat his patients. 1. Zimmerman, M.B. (2008). Research on Iodine Deficiency and Goiter in the 19th and Early 20th Centuries. Journal Research and the Scientific Method | 35  Experimental test. Coindet administered iodine tincture orally to his patients with goiter. Interpret results. Coindet’s iodine treatment was successful. Hypothesis. French chemist Chatin proposed that the low iodine content in food and water in certain areas far away from the ocean was the primary cause of goiter, and renounced the theory that goiter was the result of poor hygiene. Experimental test. In the late 1860s the program, “The stamping- out of goiter,” started with people in several villages in France being given iodine tablets. Results. The program was effective and 80 percent of goitrous children were cured. Hypothesis. In 1918, Swiss doctor Bayard proposed iodizing salt as a good way to treat areas endemic with goiter. Experimental test. Iodized salt was transported by mules to a small village at the base of the Matterhorn where more than 75 percent of school children were goitrous. It was given to families to use for six months. Results. The iodized salt was beneficial in treating goiter in this remote population. Experimental test. Physician David Marine conducted the first experiment of treating goiter with iodized salt in America in Akron, 2 Ohio. of Nutrition, 138(11), 2060–63. http://jn.nutrition.org/ content/138/11/2060.full 2. Carpenter, K.J. (2005). David Marine and the Problem of Goiter. Journal of Nutrition, 135(4), 675–80. http://jn.nutrition.org/content/135/4/ 675.full?sid=d06fdd35-566f -42a2-a3fd- ef be0736b7ba 36 | Research and the Scientific Method  Results. This study was conducted on over four-thousand school children, and found that iodized salt prevented goiter. Conclusions. Seven other studies similar to Marine’s were conducted in Italy and Switzerland, which also demonstrated the effectiveness of iodized salt in treating goiter. In 1924, US public health officials initiated the program of iodizing salt and started eliminating the scourge of goiter. Today, more than 70% of American households use iodized salt and many other countries have followed the same public health strategy to reduce the health consequences of iodine deficiency. Career Connection What are some of the ways in which you think like a scientist, and use the scientific method in your everyday life? Any decision-making process uses some aspect of the scientific method. Think about some of the major decisions you have made in your life and the research you conducted that supported your decision. For example, what brand of computer do you own? Where is your money invested? What college do you attend? Evidence-Based Approach to Nutrition It took more than one hundred years from iodine’s discovery as an effective treatment for goiter until public health programs recognized it as such. Although a lengthy process, the scientific method is a productive way to define essential nutrients and determine their ability to promote health and prevent disease. The Research and the Scientific Method | 37  scientific method is part of the overall evidence-based approach to 3 designing nutritional guidelines. An evidence-based approach to 4 nutrition includes : Defining the problem or uncertainty (e.g., the incidence of goiter is lower in people who consume seaweed) Formulating it as a question (e.g., Does eating seaweed decrease the risk of goiter?) Setting criteria for quality evidence Evaluating the body of evidence Summarizing the body of evidence and making decisions Specifying the strength of the supporting evidence required to make decisions Disseminating the findings The Food and Nutrition Board of the Institute of Medicine, a nonprofit, non-governmental organization, constructs its nutrient recommendations (i.e., Dietary Reference Intakes, or DRI) using an evidence-based approach to nutrition. The entire procedure for setting the DRI is documented and made available to the public. The same approach is used by the USDA and HHS, which are 3. Myers E. (2003). Systems for Evaluating Nutrition Research for Nutrition Care Guidelines: Do They Apply to Population Dietary Guidelines? Journal of the American Dietetic Association, 12(2), 34–41. http://jandonline.org/article/S0002-8223(03)01378-6/ abstract 4. Briss PA, Zara S, et al. (2000). Developing an Evidence- Based Guide to Community Preventive Services—Methods. Am J Prev Med, 18(1S), 35–43. https://www.ncbi.nlm.nih.gov/pubmed/10806978 38 | Research and the Scientific Method departments of the US federal government. The USDA and HHS websites are great tools for discovering ways to optimize health; however, it is important to gather nutrition information from multiple resources, as there are often differences in opinion among various scientists and public health organizations. Full text versions of the DRI publications are available in pdf format at https://www.nap.edu/, along with many other free publications. Learning Activities Technology Note: The second edition of the Human Nutrition Open Educational Resource (OER) textbook features interactive learning activities. These activities are available in the web-based textbook and not available in the downloadable versions (EPUB, Digital PDF, Print_PDF, or Open Document). Learning activities may be used across various mobile devices, however, for the best user experience it is strongly recommended that users complete these activities using a desktop or laptop computer and in Google Chrome. An interactive or media element has been excluded from this version of the text. You can view it online here: Research and the Scientific Method | 39  http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=61 An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=61 An interactive or media element has been excluded from this version of the text. You can view it online here: http://pressbooks.oer.hawaii.edu/ humannutrition2/?p=61 40 | Research and the Scientific Method Types of Scientific Studies UNIVERSITY OF HAWAI‘I AT MĀNOA FOOD SCIENCE AND HUMAN NUTRITION PROGRAM AND HUMAN NUTRITION PROGRAM There are various types of scientific studies on humans that can be used to provide supporting evidence for a particular hypothesis. These include epidemiological studies, interventional clinical trials, and randomized clinical trials. Valuable nutrition knowledge also is obtained from animal studies and cellular and molecular biology research. Table 1.4 Types of Scientific Studies Types of Scientific Studies | 41 Type Description Example Notes Observational study of Diets with a high populations consumption of Does not around the saturated fat are determine Epidemiological world and the associated with an cause-and-effect impact of increased risk of relationships. nutrition on heart attacks. health. Testing the effect of different diets on blood pressure. Scientific One group investigations If done correctly, consumes an where a it does Intervention American diet, variable is determine Clinical Trials group 2 eats a diet changed cause-and-effect rich in fruits and between relationships. vegetables, and groups. group 3 eats a combination of groups 1 and 2. Participants Testing the effect are assigned of calcium by chance to supplements on separate women with groups that osteoporosis. compare Participants are different given a pill daily of Considered the Randomized treatments. a placebo or “gold” standard Clinical Trials Neither the calcium for scientific researchers supplement. studies. nor the Neither the participants participant nor can choose the researcher which group a know what group participant is the participant is assigned. in. Testing the effects Less expensive of a new blood than human Studies are pressure drug on trials. Study is Animal and conducted on guinea pigs or on not on whole Cellular Biology animals or on the lipid humans so it cells. membrane of a may be not cell. applicable. 42 | Types of Scientific Studies Nutrition Assessment Nutritional assessment is the interpretation of anthropometric, biochemical (laboratory), clinical and dietary data to determine whether a person or groups of people are well nourished or malnourished (overnourished or undernourished). Nutritional assessment can be done using the ABCD methods. These refer to the following: A. Anthropometry B. Biochemical methods C. Clinical methods D. Dietary methods Anthropometry methods of assessing nutritional status The word anthropometry comes from two words: Anthropo means ‘human’ and metry means ‘measurement’. The different measurements taken to assess growth and body composition are presented below. To assess growth, several different measurements including length, height, weight, head circumference, mid-arm circumference, skin-fold thickness, head/chest ratio, and hip/waist ratio can be used. Height and weight measurements are essential in children to evaluate physical growth. As an additional resource, the NHANES Anthropometry Procedures Manual (revised January 2004) can be viewed here https://www.cdc.gov/nchs/data/nhanes/ nhanes_03_04/BM.pdf Figure 1.3 Measuring Height Types of Scientific Studies | 43  (Source: UNICEF, 1986, How to weigh and measure children: assessing the nutrition status of young children) Biochemical methods of assessing nutritional status Biochemical or laboratory methods of assessment include measuring a nutrient or its metabolite in the blood, feces, urine or other tissues that have a relationship with the nutrient. An example of this method would be to take blood samples to measure levels of glucose in the body. This method is useful for determining if an individual has diabetes. Figure 1.4 Measuring Blood Glucose Levels 44 | Types of Scientific Studies  Image by TesaPhotogr aphy / CC0 Clinical methods of assessing nutritional status In addition to the anthropometric assessments, you can also assess clinical signs and symptoms that might indicate potential specific nutrient deficiency. Special attention are given to organs such as skin, eyes, tongue, ears, mouth, hair, nails, and gums. Clinical methods of assessing nutritional status involve checking signs of deficiency at specific places on the body or asking the patient whether they have any symptoms that might suggest nutrient deficiency. Dietary methods of assessing nutritional status Dietary methods of assessment include looking at past or current intakes of nutrients from food by individuals or a group to determine their nutritional status. There are several methods used to do this: Types of Scientific Studies | 45 24 hour recall A trained professional asks the subject to recall all food and drink consumed in the previous 24 hours. This is a quick and easy method. However, it is dependent upon the subject’s short-term memory and may not be very accurate. Food frequency questionnaire The subject is given a list of foods and asked to indicate intake per day, per week, and per month. This method is inexpensive and easy to administer. It is more accurate than the 24 hour recall. Food Diary Food intake is recorded by the subject at the time of eating. This method is reliable but difficult to maintain. Also known as a food journal or food record. Observed food consumption This method requires food to be weighed and exactly calculated. It is very accurate but rarely used because it is time-consuming and expensive. Evolving Science Science is always moving forward, albeit sometimes slowly. One study is not enough to make a guideline or a recommendation, or 46 | Types of Scientific Studies cure a disease. Science is a stepwise process that builds on past evidence and finally culminates into a well-accepted conclusion. Unfortunately, not all scientific conclusions are developed in the interest of human health, and some can be biased. Therefore, it is important to know where a scientific study was conducted and who provided the funding, as this can have an impact on the scientific conclusions being made. For example, an air quality study paid for by a tobacco company diminishes its value in the minds of readers as well as a red meat study performed at a laboratory funded by a national beef association. Nutritional Science Evolution One of the newest areas in the realm of nutritional science is the scientific discipline of nutritional genetics, also called nutrigenomics. Genes are part of DNA and contain the genetic information that make up all of our traits. Genes are codes for proteins and when they are turned “on” or “off,” they change how the body works. While we know that health is defined as more than just the absence of disease, there are currently very few accurate genetic markers of good health. Rather, there are many more genetic markers for disease. However, science is evolving, and nutritional genetics aims to identify what nutrients to eat to “turn on” healthy genes and “turn off” genes that cause disease. Using Science and Technology to Change the Future As science evolves, so does technology. Both can be used to create a healthy diet, optimize health, and prevent disease. Picture yourself not too far into the future: you are wearing a small “dietary watch” Types of Scientific Studies | 47 that painlessly samples your blood, and downloads the information to your cell phone, which has an app that evaluates the nutrient profile of your blood and then recommends a snack or dinner menu to assure you maintain adequate nutrient levels. What else is not far off? How about another app that provides a shopping list that adheres to all dietary guidelines and is emailed to the central server at your local grocer, who then delivers the food to your home? The food is then stored in your smart fridge which documents your daily diet at home and delivers your weekly dietary assessment to your home computer. At your computer, you can compare your diet with other diets aimed at weight loss, optimal strength training, reduction in risk for specific diseases or any other health goals you may have. You also may delve into the field of nutritional genetics and download your gene expression profiles to a database that analyzes your genes against millions of others. Nutrition and the Media A motivational speaker once said, “A smart person believes half of what they read. An intelligent person knows which half to believe.” In this age of information, where instant Internet access is just a click away, it is easy to be misled if you do not know where to go for reliable nutrition information. Using Eyes of Discernment “New study shows that margarine contributes to arterial plaque.” “Asian study reveals that two cups of coffee per day can have detrimental effects on the nervous system.” How do you react when you read news of this nature? Do you boycott margarine and coffee? When reading nutrition-related 48 | Types of Scientific Studies claims, articles, websites, or advertisements, always remember that one study does not substantiate a fact. One study neither proves nor disproves anything. Readers who may be looking for complex answers to nutritional dilemmas can quickly misconstrue such statements and be led down a path of misinformation. Listed below are ways that you can develop discerning eyes when reading nutritional news. 1. The scientific study under discussion should be published in a peer reviewed journal, such as the Journal of Nutrition. Question studies that come from less trustworthy sources (such as non peer-reviewed journals or websites) or that are not formally published. 2. The report should disclose the methods used by the researcher(s). Did the study last for three or thirty weeks? Were there ten or one hundred participants? What did the participants actually do? Did the researcher(s) observe the results themselves or did they rely on self reports from program participants? 3. Who were the subjects of this study? Humans or animals? If human, are any traits/characteristics noted? You may realize you have more in common with certain program participants and can use that as a basis to gauge if the