The Nutritionist: Food, Nutrition, and Optimal Health, 2nd Edition

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The Nutritionist

Now in an updated and expanded new edition, The Nutritionist: Food, Nutrition, and Optimal Health, Second Edition, provides readers with vital information about how to simply but radically improve their daily lives with the science of nutrition, balance their diets to achieve more energy, and improve health and longevity. Complete with many informative and easy-to-read tables and charts, The Nutritionist: Food, Nutrition, and Optimal Health, Second Edition, utilizes the findings of the latest biological and medical studies to give experts and non-experts alike a comprehensive account of the needs of our bodies and the ways that healthy eating can improve performance in day-to-day activities. Author Dr Robert Wildman, renowned nutrition expert, debunks myths about carbohydrates, fat, and cholesterol, elucidates the role of water in nutrition, and clearly explains the facts of human anatomy and physiognomy, the process of digestion, and vitamin supplements. Complete with a practical and comprehensive guide to the nutrition information printed on the packaging of most food items, The Nutritionist: Food, Nutrition, and Optimal Health, Second Edition is a necessary and extremely useful nutrition resource for anyone interested in the science and practical benefits of good nutrition. Dr Robert E.C. Wildman is a graduate of the University of Pittsburgh, Florida State University, and Ohio State University, and is currently on the faculty at Kansas State University. Dr Wildman is also the author of Sports and Fitness Nutrition (2002) and editor of The Handbook of Nutraceuticals and Functional Foods, Second Edition (Taylor & Francis, 2007).

The Nutritionist Food, Nutrition, and Optimal Health Second Edition

Dr Robert E. C. Wildman

First published 2002 by Haworth This edition first published 2009 by Routledge 270 Madison Ave, New York, NY 10016 Simultaneously published in the UK by Routledge 2 Park Square, Milton Park, Abingdon, Oxon OX14 4RN Routledge is an imprint of the Taylor & Francis Group, an informa business This edition published in the Taylor & Francis e-Library, 2009. “To purchase your own copy of this or any of Taylor & Francis or Routledge’s collection of thousands of eBooks please go to www.eBookstore.tandf.co.uk.” © 2002 Haworth © 2009 Taylor & Francis All rights reserved. No part of this book may be reprinted or reproduced or utilized in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Library of Congress Cataloging in Publication Data Wildman, Robert E. C., 1964– The nutritionist: food, nutrition & optimal health / by Robert E.C. Wildman. p. cm. 1. Nutrition. I. Title QP141.W487 2009 612.3—dc22 2008029707 ISBN 0-203-88700-X Master e-book ISBN

ISBN10: 0–7890–3423–9 (hbk) ISBN10: 0–7890–3424–7 (pbk) ISBN10: 0–203–88700–X (ebk) ISBN13: 978–0–7890–3423–6 (hbk) ISBN13: 978–0–7890–3424–3 (pbk) ISBN13: 978–0–203–88700–4 (ebk)

For David

Contents

About the Author Preface 1 The Very Basics of Humans and the World We Inhabit

ix x

1

2 How Our Body Works

18

3 The Nature of Food

49

4 Carbohydrates Are Our Most Basic Fuel Source

66

5 Fats and Cholesterol Are Not All Bad

96

6 Proteins Are the Basis of Our Structure and Function

124

7 Water is the Basis of Our Body

145

8 Energy Metabolism, Body Weight and Composition, and Weight

155

9 Vitamins Are Vital Molecules in Food

191

10 The Minerals of Our Body

233

11 Exercise and Sports Nutrition

274

12 Nutrition Throughout Life

307

viii Contents

13 Nutrition, Heart Disease, and Cancer Appendix A: Periodic Table of Elements Index

334 365 367

About the Author

Dr Robert E.C. Wildman is a graduate of the University of Pittsburgh, Florida State University, and Ohio State University, and is currently on the faculty at Kansas State University. Dr Wildman is also the author of Sports and Fitness Nutrition (2002) and editor of The Handbook of Nutraceuticals and Functional Foods, Second Edition (Taylor & Francis, 2007) as well as founder of TheNutritionDr.com (www.thenutritiondr.com) and Demeter Consultants LLC (www. demeterconsultants.com).

Preface

The seeming simplicity of our daily activities is greatly contrasted by the complexity of our true nature—quite a paradox, no doubt. It is simple in that, on the outside, the goals of our body may appear few. We internalize food, water, and oxygen while at the same time ridding ourselves of carbon dioxide and other waste materials. These operations support reproduction, growth, maintenance, and defense. Yet on the inside our body may seem very complex as various organs participate in a tremendous number of complicated processes intended to meet the simple goals previously mentioned. Nutrition is just one part of this paradoxical relationship. The objective of nutrition is simple: to supply our body with all of the necessary nutrients, and in appropriate quantities, to promote optimal health and function. However, in practice, nutrition is far from that simple. There seem to be too many nutrients, controversial nutrients, and different conditions, such as growth, pregnancy, and exercise, to allow nutrition to be a simple topic. Although we have long appreciated food, it has only been in the more recent years that we have really begun to understand the finer relationship between food and our body. Most nutrients have been identified within the last century or so and right now nutrition is one of the most prevalent areas of scientific research. This is to say that our understanding of nutrition is by no means complete. It continues to evolve in conjunction with the most current nutrition research. It seems that not a week goes by without hearing about yet another discovery in nutrition. It is hard to believe that just a few decades ago the basic four food groups were pretty much all the nutrition known by most people. Today nutrition deeply penetrates into many aspects of our lives, including preventative and treatment medicine, philosophy, exercise training, and weight management. Our diet has been linked to cardiovascular health, cancer, bowel function, moods, and brain activity, along with many other health domains. We no longer eat merely to satisfy hunger. Without doubt, nutrition has become a matter of great curiosity and/or concern for most of us today.

Preface

xi

A few problems have developed along with this most recent illumination of nutrition. One such problem is that we may have generated too much knowledge too fast. Even though we, as humans, have been eating throughout our existence, the importance of proper nutrition seems to have been thrust upon us suddenly. We did not have time to first wade into the waters of nutrition science, slowly increasing our depth. The reality is that we may be in over our heads, barely treading water to keep up with the latest recommendations. Sometimes, all we can do is try our best to follow the latest nutrition recommendations without really having the background or accessibility to proper resources truly to understand the reasons behind the recommendations. Although nutrition has become a very complex subject many authors still try to present it in an overly simplified manner. Perhaps they believe that people are not interested in the scientific details and merely wish to be told what to do. This book attempts to break that pattern. We will spend time laying a foundation in some of the basic concepts of science and of our body in hope that it will actually make nutrition a simpler subject. I believe that deep down a scientist lurks within all of us. Everyday we ponder the effects of certain actions before performing them. This is the so-called cause and effect relationship, the very basis of scientific experimentation. Furthermore, since most of us give at least some thought to the foods we eat, we are all a special breed of scientist. We are nutrition scientists! A nutrition scientist is one who ponders the relationship between food components and their body. You do not have to work in a laboratory to be a nutrition scientist. All you need is simple curiosity and the dedication of your time to pursue a greater understanding of nutrition. This book is written in a question and answer format to satisfy your curiosity. Fundamental questions regarding nutrition and our body will be posed and then answered based upon the most current research. If your educational background includes a solid foundation of biology and chemistry you may wish to skip the first few chapters. However, if your science background is weak or far in the past, you may find the first few chapters of service. So, here we go. Good luck and good science!

1

The Very Basics of Humans and the World We Inhabit

Have you ever stopped and wondered why we (humans) are as we are, and why we do what we do? It is truly remarkable what our bodies are capable of doing and how our bodies operate to perform various tasks. Yet, we are just one of millions of different species inhabiting this planet, all with a unique story to tell. And, like our fellow planet-mates, we must abide by the basic objectives of life, namely to function as an independent being (self-operate), defend ourselves both externally and internally, nourish ourselves, and of course to reproduce, which is without question the ultimate objective of all life-forms. Yet, we are special in that we have a relatively large brain and the intellectual capacity to try to understand ourselves and, in accordance, how we are to be nourished. In this chapter we will begin to explore the very basis of our being and the world we live in. This will begin to set the stage for understanding what it will take to nourish our body for optimal health and longevity. We will answer questions about basic concepts such as elements, atoms, molecules, oxidation, chemical reactions, water solubility, and acids and bases. If you have a science background this chapter might seem too rudimentary and you might consider moving on to the next chapter.

What Is Nutrition? We will start out as simply as possible. The shortest definition of nutrition is the science pertaining to the factors involved in nourishing our body. Nutrition hinges upon the special relationship that exists between our body and the world we live in. From the moment of conception to the waning hours of advanced age, we live in a continuum to nourish our body. More specifically, we strive on a daily basis to bring nourishing substances into our body. These nourishing substances are called nutrients, which are chemicals that are used by our body for energy or other human processes. Proper nourishment supports body businesses such as growth, movement, immunity, injury recovery, and disease prevention, and, of course, the ultimate business at hand for all life-forms, reproduction.

2

The Very Basics of Humans

All that we (our body) are, ever were, or are going to be is borrowed from the environment that we inhabit. This unique state of indebtedness is primarily attributed to our nutrition intake. We must be grateful to the earth’s crust for lending us minerals that strengthen our bones and teeth and allow us to have electrical operations that drives nerve and muscle function. We must also pay homage to plants for the carbohydrate forms that power our operations and for the amino acids that make the protein in our muscle. Nutrition refers to the science of nourishing our body.

All too often we do not truly appreciate the relevance of nutrition to our basic being. But again, please keep in mind that nearly everything we are and are able to do is either a direct or indirect reflection of our past and current nutrition intake. No matter how oversimplified nutrition may seem in television commercials and on cereal boxes, it is without a doubt one of the most complex and interesting sciences out there. One of the major tasks of this book is to provide an understandable overview of nutrition as it applies to optimal health and longevity. How Do We Begin to Understand Nutrition? Certainly any great building must be constructed upon a solid foundation. So let us go ahead and commit ourselves to building a solid scientific foundation to explore nutrition. So, before we begin to learn how to nourish our body, we need to have a better understanding of what needs to be nourished. Our body is the product of nature and as such it must adhere to the basic laws of nature. In fact, you can think of nutrition as the scientific offspring of more basic sciences such as chemistry and biology. Therefore, understanding the what’s, why’s, and how’s of nutrition will be a lot easier once a few basic areas of chemistry and biology are appreciated. What follows are some fundamental principles of chemistry and biology and a description of their relevance to nutrition and the body.

It’s Atoms and Molecules That Make the Man, Not Clothes What Is the Most Basic Composition of Our Body? Let’s say that we had access to fancy laboratory equipment capable of determining the most fundamental composition of an object. If we used this equipment to assess a man or woman it would spit out some interesting data on our most basic level of composition—elements. Elements are

The Very Basics of Humans

3

substances that cannot be broken down into other substances. Scientists have determined that there are one hundred or so of these elements in nature. Some of the more recognizable elements include carbon, oxygen, hydrogen, nitrogen, iron, zinc, copper, potassium, and calcium. All of the elements known to exist can be found on the periodic table of elements, which we have all come across at one point or another in our schooling. (the periodic table of elements is included as Appendix A in case you feel the need for another peek.) Now, imagine that everything that you can think of is merely a skillful combination of these same elements. This includes cars, boats, buildings, clouds, oceans, trees, and of course our body. In fact, our body employs about twenty-seven of the elements as displayed in Table 1.1 and Appendix A. What Is the Element Composition of Our Body? The late, great Carl Sagan in his personal exploration of the cosmos said that we are made up of “star stuff.” What he meant was that our body is made up of many of the very same elements that make up planets and other celestial bodies in the universe. We humans, as well as other lifeforms on our planet, have simply borrowed these elements. Interestingly, four of these elements, namely oxygen, carbon, hydrogen, and nitrogen, make up greater than 90 percent of our body weight. Since the majority of these elements are found in our body as part of substances such as water, proteins, carbohydrates, fats, and nucleic acids (DNA and RNA), it only makes sense that these substances must be the major chemicals of Table 1.1 Elements of Our Bodies Major Elements (>0.1% Body Weight)

Percentage of Body Weight

Minor Elements (