Contents
Acknowledgments ix
Introduction xi
Chapter 1: A Cultural Context for Human-Microbe Symbiosis 1
Evolution of the Human Diet: What Our Ancestors
Ate and Why It Matters 2
The Industrialized Western Diet 13
Conclusion 16
Chapter 2: The Gastrointestinal Tract and Its Microorganisms 17
Classification of Gut Bacteria 18
Introduction to the Gastrointestinal Tract and Its Microorganisms 22
The Stomach and Small Intestine 24
The Large Intestine 28
Bacteroidetes, Firmicutes, and Actinobacteria 31
Archaea and Fungi 36
Baby’s First Encounter with Microorganisms 41
The Aging Microbiome 44
Conclusion 44
Chapter 3: Nutrition and the Gut Microbiota 45
Culture, Diet, and Varying Gut Microbiota Populations 45
Carbohydrates: Nutrition for Host and Commensal Bacteria 50
Bacterial Metabolism 57
Conclusion 73
Chapter 4: Immunity 75
Microbes Influence the Development and Function of the
Immune System 76
Innate and Adaptive Immunity 81
Acknowledgments ix
Introduction xi
Chapter 1: A Cultural Context for Human-Microbe Symbiosis 1
Evolution of the Human Diet: What Our Ancestors
Ate and Why It Matters 2
The Industrialized Western Diet 13
Conclusion 16
Chapter 2: The Gastrointestinal Tract and Its Microorganisms 17
Classification of Gut Bacteria 18
Introduction to the Gastrointestinal Tract and Its Microorganisms 22
The Stomach and Small Intestine 24
The Large Intestine 28
Bacteroidetes, Firmicutes, and Actinobacteria 31
Archaea and Fungi 36
Baby’s First Encounter with Microorganisms 41
The Aging Microbiome 44
Conclusion 44
Chapter 3: Nutrition and the Gut Microbiota 45
Culture, Diet, and Varying Gut Microbiota Populations 45
Carbohydrates: Nutrition for Host and Commensal Bacteria 50
Bacterial Metabolism 57
Conclusion 73
Chapter 4: Immunity 75
Microbes Influence the Development and Function of the
Immune System 76
Innate and Adaptive Immunity 81
