Understanding Nutrition, Sixteenth Edition
By Ellie Whitney and Sharon Rady Rolfes
Table of Contents:
Preface xiii
Acknowledgments xvii
Reviewers of Recent Editions xviii
CHAPTER 1
An Overview of Nutrition 2
1.1 Food Choices 3
1.2 The Nutrients 6
Nutrients in Foods and in the Body 6
The Energy-Yielding Nutrients: Carbohydrate, Fat, and
Protein 7
The Vitamins 7
The Minerals 11
Water 11
1.3 The Science of Nutrition 12
Conducting Research 12
Analyzing Research Findings 14
Publishing Research 16
1.4 Dietary Reference Intakes (DRI) 17
Establishing Nutrient Recommendations 17
Establishing Energy Recommendations 20
Using Nutrient Recommendations 21
Comparing Nutrient Recommendations 21
1.5 Nutrition Assessment 22
Nutrition Assessment of Individuals 22
Nutrition Assessment of Populations 24
1.6 Diet and Health 25
Risk Factors for Chronic Diseases 26
Highlight 1 > Nutrition Information and Misinformation 28
CHAPTER 2
Planning a Healthy Diet 34
2.1 Principles and Guidelines 35
Diet-Planning Principles 35
Dietary Guidelines for Americans 38
2.2 Diet-Planning Guides 40
USDA Food Patterns 40
Food Lists 47
Putting the Plan into Action 47
From Guidelines to Groceries 49
2.3 Food Labels 53
The Ingredient List 53
Nutrition Facts Panel 54
Claims on Labels 56
Consumer Education 58
Highlight 2 > Plant-Based Diets 60
CHAPTER 3
Digestion, Absorption, and Transport 66
3.1 Digestion 67
Anatomy of the Digestive Tract 68
The Muscular Action of Digestion 70
The Secretions of Digestion 71
The Final Stage 72
3.2 Absorption 74
Anatomy of the Absorptive System 75
A Closer Look at the Intestinal Cells 75
3.3 The Circulatory Systems 77
The Vascular System 77
The Lymphatic System 79
3.4 The Health and Regulation of the GI Tract 80
Gastrointestinal Microbes 80
Gastrointestinal Hormones and Nerve Pathways 80
The System at Its Best 83
Highlight 3 > Common Digestive Problems 85
CHAPTER 4
The Carbohydrates: Sugars, Starches,
and Fibers 92
4.1 The Chemist’s View of Carbohydrates 93
Monosaccharides 94
Disaccharides 95
Polysaccharides 96
4.2 Digestion and Absorption of Carbohydrates 99
Carbohydrate Digestion 99
Carbohydrate Absorption 101
Lactose Intolerance 101
4.3 Glucose in the Body 103
A Preview of Carbohydrate Metabolism 103
The Constancy of Blood Glucose 104
4.4 Health Effects and Recommended Intakes of Sugars 107
Health Effects of Sugars 108
Recommended Intakes of Sugars 111
Alternative Sweeteners 112
4.5 Health Effects and Recommended Intakes of Starch and
Fibers 114
Health Effects of Starch and Fibers 114
Recommended Intakes of Starch and Fibers 117
From Guidelines to Groceries 118
Highlight 4 > Carbs, kCalories, and Controversies 122
CHAPTER 5
The Lipids: Triglycerides, Phospholipids,
and Sterols 126
5.1 The Chemist’s View of Fatty Acids and Triglycerides 127
Fatty Acids 128
Triglycerides 130
Characteristics of Solid Fats and Oils 131
5.2 The Chemist’s View of Phospholipids and Sterols 134
Phospholipids 134
Sterols 135
5.3 Digestion, Absorption, and Transport of Lipids 136
Lipid Digestion 136
Lipid Absorption 139
Lipid Transport 139
5.4 Lipids in the Body 142
Roles of Triglycerides 142
Essential Fatty Acids 143
A Preview of Lipid Metabolism 144
5.5 Health Effects and Recommended Intakes of Saturated
Fats, Trans Fats, and Cholesterol 145
Health Effects of Saturated Fats, Trans Fats, and Cholesterol 146
Recommended Intakes of Saturated Fat, Trans Fat, and
Cholesterol 147
5.6 Health Effects and Recommended Intakes of
Monounsaturated and Polyunsaturated Fats 147
Health Effects of Monounsaturated and Polyunsaturated
Fats 148
Recommended Intakes of Monounsaturated and
Polyunsaturated Fats 149
From Guidelines to Groceries 150
Highlight 5 > High-Fat Foods—Friend or Foe? 158
CHAPTER 6
Protein: Amino Acids 166
6.1 The Chemist’s View of Proteins 167
Amino Acids 167
Proteins 169
6.2 Digestion and Absorption of Proteins 170
Protein Digestion 170
Protein Absorption 172
6.3 Proteins in the Body 172
Protein Synthesis 172
Roles of Proteins 175
A Preview of Protein Metabolism 178
6.4 Protein in Foods 180
Protein Quality 181
Complementary Proteins 181
6.5 Health Effects and Recommended Intakes of Protein 182
Health Effects of Protein 182
Recommended Intakes of Protein 183
From Guidelines to Groceries 184
Read Food Labels 185
Protein and Amino Acid Supplements 185
Highlight 6 > Nutritional Genomics 188
CHAPTER 7
Energy Metabolism 194
7.1 Chemical Reactions in the Body 195
7.2 Breaking Down Nutrients for Energy 198
Glucose 200
Glycerol and Fatty Acids 203
Amino Acids 205
The Final Steps of Energy Metabolism 206
7.3 Feasting and Fasting 211
Feasting—Excess Energy 211
The Transition from Feasting to Fasting 212
Fasting—Inadequate Energy 212
Low-Carbohydrate Diets 215
Highlight 7 > Alcohol in the Body 218
CHAPTER 8
Energy Balance and Body Composition 228
8.1 Energy Balance 229
8.2 Energy In: The kCalories Foods Provide 230
Food Composition 230
Food Intake 231
8.3 Energy Out: The kCalories the Body Expends 233
Components of Energy Expenditure 233
Estimating Energy Requirements 236
8.4 Body Weight and Body Composition 238
Defining Healthy Body Weight 238
Body Fat and Its Distribution 240
8.5 Health Risks Associated with Body Weight and Body Fat 243
Health Risks of Underweight 243
Health Risks of Overweight and Obesity 243
Other Considerations 245
Highlight 8 > Eating Disorders 248
CHAPTER 9
Weight Management: Overweight, Obesity,
and Underweight 256
9.1 Overweight and Obesity 257
Fat Cell Development 257
Fat Cell Metabolism 258
Set-Point Theory 259
9.2 Causes of Overweight and Obesity 259
Genetics and Epigenetics 259
Environment 262
9.3 Problems of Overweight and Obesity 264
Health Risks 264
Perceptions and Prejudices 264
Dangerous Interventions 265
9.4 Aggressive Treatments for Obesity 266
Drugs 266
Surgery 266
Other Medical Procedures 267
9.5 Lifestyle Strategies 268
Changes, Losses, and Goals 268
Eating Patterns 268
Physical Activity 271
Environmental Influences 273
Behavior and Attitude 274
Weight Maintenance 276
Prevention 277
Community Programs 277
9.6 Underweight 278
Problems of Underweight 278
Weight-Gain Strategies 278
Highlight 9 > The Latest and Greatest Weight-Loss
Diet—Again 284
CHAPTER 10
The Water-Soluble Vitamins: B Vitamins
and Vitamin C 288
10.1 The Vitamins—An Overview 289
10.2 The B Vitamins 292
Thiamin 293
Riboflavin 296
Niacin 298
Biotin 300
Pantothenic Acid 300
Vitamin B6 301
Folate 303
Vitamin B12 307
Choline 309
Nonvitamins 309
Interactions among the B Vitamins 309
10.3 Vitamin C 313
Vitamin C Roles 314
Vitamin C Recommendations 315
Vitamin C Deficiency 316
Vitamin C Toxicity 316
Vitamin C Food Sources 317
Highlight 10 > Vitamin and Mineral Supplements 321
CHAPTER 11
The Fat-Soluble Vitamins: A, D, E, and K 328
11.1 Vitamin A and Beta-Carotene 329
Vitamin A Roles 330
Vitamin A Deficiency 332
Vitamin A Toxicity 333
Vitamin A Recommendations 334
Vitamin A Food Sources 334
11.2 Vitamin D 336
Vitamin D Roles 337
Vitamin D Deficiency 338
Vitamin D Toxicity 339
Vitamin D Recommendations and Sources 339
11.3 Vitamin E 341
Vitamin E Roles 342
Vitamin E Deficiency 342
Vitamin E Toxicity 342
Vitamin E Recommendations 342
Vitamin E Food Sources 342
11.4 Vitamin K 343
Vitamin K Roles 343
Vitamin K Deficiency 343
Vitamin K Toxicity 344
Vitamin K Recommendations and Sources 344
Highlight 11 > Antioxidant Nutrients in Disease Prevention 348
CHAPTER 12
Water and the Major Minerals 352
12.1 Water and the Body Fluids 353
Distribution and Movement of Body Fluids 354
Regulation of Fluid Balance 356
Fluid and Electrolyte Imbalance 357
Acid–Base Balance 358
Water Balance and Recommended Intakes 360
12.2 The Minerals—An Overview 363
12.3 The Major Minerals 364
Sodium 364
Chloride 367
Potassium 368
Calcium 370
Phosphorus 374
Magnesium 376
Sulfur 377
Highlight 12 > Osteoporosis and Calcium 380
CHAPTER 13
The Trace Minerals 386
13.1 The Trace Minerals—An Overview 387
13.2 The Trace Minerals 389
Iron 389
Zinc 398
Copper 401
Manganese 402
Iodine 403
Selenium 404
Fluoride 405
Chromium 406
Molybdenum 406
13.3 Contaminant Minerals 407
Highlight 13 > Phytochemicals and Functional Foods 410
CHAPTER 14
Fitness: Physical Activity, Nutrients, and Body
Adaptations 416
14.1 Fitness 417
Benefits of Fitness 417
Developing Fitness 420
The Components of Fitness 421
Cardiorespiratory Endurance 421
Muscle Strength and Endurance 422
14.2 Energy Systems and Fuels to Support Activity 423
The Energy Systems of Physical Activity 423
Glucose Use during Physical Activity 425
Fat Use during Physical Activity 428
Protein Use during Physical Activity—and between
Times 428
14.3 Vitamins and Minerals to Support Activity 431
Dietary Supplements 431
Iron—A Mineral of Concern 431
14.4 Fluids and Electrolytes to Support Activity 432
Temperature Regulation 433
Sports Drinks 435
Poor Beverage Choices: Caffeine and Alcohol 437
14.5 Diets for Physically Active People 437
Choosing a Diet to Support Fitness 437
Meals before and after Competition 439
Highlight 14 > Supplements as Ergogenic Aids 443
CHAPTER 15
Life Cycle Nutrition: Pregnancy and Lactation 448
15.1 Nutrition prior to Pregnancy 449
15.2 Growth and Development during Pregnancy 450
Placental Development 450
Fetal Growth and Development 450
Critical Periods 452
15.3 Maternal Weight 455
Weight prior to Conception 455
Weight Gain during Pregnancy 455
Exercise during Pregnancy 457
15.4 Nutrition during Pregnancy 458
Energy and Nutrient Needs during Pregnancy 459
Common Nutrition-Related Concerns of Pregnancy 462
15.5 High-Risk Pregnancies 463
The Infant’s Birthweight 464
Malnutrition and Pregnancy 464
Food Assistance Programs 465
Maternal Health 465
The Mother’s Age 466
Practices Incompatible with Pregnancy 468
15.6 Nutrition during Lactation 470
Lactation: A Physiological Process 471
Breastfeeding: A Learned Behavior 471
Maternal Energy and Nutrient Needs
during Lactation 472
Maternal Health 474
Practices Incompatible with Lactation 475
Highlight 15 > Fetal Alcohol Syndrome 479
CHAPTER 16
Life Cycle Nutrition: Infancy, Childhood,
and Adolescence 482
16.1 Nutrition during Infancy 483
Energy and Nutrient Needs 483
Breast Milk 485
Infant Formula 488
Special Needs of Preterm Infants 490
Introducing Cow’s Milk 490
Complementary Foods 491
Mealtimes with Toddlers 494
16.2 Nutrition during Childhood 495
Energy and Nutrient Needs 495
Hunger and Malnutrition in Children 497
The Malnutrition-Lead Connection 498
Hyperactivity and “Hyper” Behavior 499
Food Allergy and Intolerance 500
Childhood Obesity 502
Mealtimes at Home 507
Nutrition at School 510
16.3 Nutrition during Adolescence 512
Growth and Development 513
Energy and Nutrient Needs 513
Food Choices and Health Habits 514
Highlight 16 > Childhood Obesity and the Early Development of
Chronic Diseases 521
CHAPTER 17
Life Cycle Nutrition: Adulthood and the
Later Years 526
17.1 Nutrition and Longevity 527
Observations of Older Adults 528
Manipulation of Diet 530
17.2 The Aging Process 532
Physiological Changes 532
Other Changes 534
17.3 Energy and Nutrient Needs of Older Adults 535
Water 536
Energy and Energy Nutrients 536
Vitamins and Minerals 537
Dietary Supplements 538
17.4 Nutrition-Related Concerns of Older Adults 539
Vision 539
Arthritis 540
The Aging Brain 540
Alcohol 543
17.5 Food Choices and Eating Habits of Older Adults 544
Malnutrition 545
Food Assistance Programs 545
Meals for Singles 546
Highlight 17 > Nutrient-Drug Interactions 550
CHAPTER 18
Disease Prevention 554
18.1 Nutrition and Infectious Diseases 555
The Immune System 556
Nutrition and Immunity 557
Inflammation and Chronic Diseases 558
18.2 Nutrition and Chronic Diseases 558
18.3 Cardiovascular Disease 560
How Atherosclerosis Develops 560
Risk Factors for Coronary Heart Disease 562
Recommendations for Reducing Cardiovascular Disease
Risk 565
18.4 Hypertension 566
How Hypertension Develops 567
Risk Factors for Hypertension 568
Recommendations for Reducing Hypertension Risk 568
18.5 Diabetes 570
How Diabetes Develops 570
Complications of Diabetes 572
Dietary Recommendations for Diabetes 573
18.6 Cancer 576
How Cancer Develops 577
Recommendations for Reducing Cancer Risks 578
18.7 Recommendations for Chronic Diseases 580
Highlight 18 > Complementary and Alternative Medicine 586
CHAPTER 19
Consumer Concerns about Foods and Water 594
19.1 Food Safety and Foodborne Illnesses 595
Foodborne Infections and Food Intoxications 596
Food Safety in the Marketplace 598
Food Safety in the Kitchen 599
Food Safety while Traveling 603
Advances in Food Safety 603
19.2 Nutritional Adequacy of Foods and Diets 606
Obtaining Nutrient Information 606
Minimizing Nutrient Losses 606
19.3 Environmental Contaminants 607
Harmfulness of Environmental Contaminants 607
Contaminants in the Food Supply 607
Guidelines for Consumers 608
19.4 Natural Toxins in Foods 609
19.5 Pesticides 610
Hazards and Regulation of Pesticides 610
Monitoring Pesticides 611
Consumer Concerns 611
19.6 Food Additives 613
Regulations Governing Additives 613
Intentional Food Additives 614
Indirect Food Additives 617
19.7 Consumer Concerns about Water 620
Sources of Drinking Water 620
Water Systems and Regulations 620
Highlight 19 > Food Biotechnology 624
CHAPTER 20
Hunger and the Environment 630
20.1 Hunger in the United States 631
Defining Hunger in the United States 632
Relieving Hunger in the United States 633
20.2 World Hunger 635
Food Shortages 636
Population Needs 637
20.3 Malnutrition 637
Nutrient Deficiencies 637
Growth Failure 638
Medical Nutrition Therapy 638
20.4 Feeding the World 639
Environmental Damage 639
Sustainable Solutions 641
Highlight 20 > Environmentally Friendly Food Choices 646
APPENDIX A
Cells, Hormones, and Nerves
APPENDIX B
Basic Chemistry Concepts
APPENDIX C
Biochemical Structures and Pathways
APPENDIX D
Measures of Protein Quality
APPENDIX E
Nutrition Assessment
APPENDIX F
Estimated Energy Needs
APPENDIX G
Choose Your Foods: Food Lists for Diabetes and Weight
Management
APPENDIX H
Aids to Calculation
APPENDIX I
WHO Nutrition Recommendations
Glossary GL-1
Index IN-1
INSIDE COVERS
Dietary Reference Intakes (DRI) A
Daily Values (DV) for Food Labels Y
Body Mass Index (BMI) Z