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In this second edition of the bestselling title from the acclaimed Nutrition Society Textbook series, Public Health Nutrition has been extensively revised to ensure that it reflects the latest evidence-based knowledge and research. Ground-breaking and comprehensive in both its scope and approach, Public Health Nutrition has been fully updated by an expert editorial team to cover the most recent changes in the field. It now offers a structured overview of the subject's core concepts and considers Public Health Nutrition tools and the application of intervention strategies. Divided into five key sections, Public Health Nutrition contains a wealth of information, including: * Public Health Nutrition concepts and assessment tools, and their application in light of the latest evidence. * Case studies to illustrate how best to apply the theory and evidence to policy and practice. * An examination of nutrition throughout the lifecycle, and the relationship between diet and disease, including in relation to obesity, diabetes, cancer, as well as mental health. * The impact of environmental factors on public health. * Public health strategies, policies and approaches. With a clear and concise structure, Public Health Nutrition is an essential purchase for students of nutrition, dietetics and other healthcare areas, as well as an invaluable practical guide for health professionals working within public health. A supporting companion website featuring multiple-choice, short answer, and essay style questions is available at www.wiley.com/go/buttriss/publichealth

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Contents

Cover

The Nutrition Society Textbook Series

Title Page

Copyright

Contributors

Series Foreword

Preface

Introduction

About the Companion Website

Part One: Public Health Nutrition Tools

Chapter 1: Introduction to Public Health Nutrition

1.1 Public Health and Nutrition

1.2 History of Nutrition in Public Health

1.3 Nutrition and Public Health in Different Parts of the World

1.4 Current Role of Nutrition in Public Health

1.5 Nutrition Through the Life Course

1.6 Principles of Public Health Nutrition

1.7 Conclusions

References

Chapter 2: Concepts and Definitions Used in Public Health Nutrition

2.1 Introduction

2.2 Nature of Evidence

2.3 Methods and Study Design

2.4 Measurement Error and Bias

2.5 Interpretation of Study Design and Hierarchy of the Evidence

2.6 Risk Assessment Versus Risk Management

2.7 Social Determinants of Diet and Health

2.8 Conclusion

References

Chapter 3: Assessment of Dietary Habits

3.1 Introduction

3.2 Dietary Assessment Methods

3.3 Selective Issues in Dietary Assessment

3.4 Conclusions

References

Chapter 4: Assessment of Nutritional Status in Public Health Nutrition Settings

4.1 Introduction

4.2 Anthropometric Measures

4.3 Assessment in Children and Adolescents: References, Norms and Percentile Charts

4.4 Conclusions

References

Chapter 5: Food Composition

5.1 Introduction

5.2 Uses of Food Composition Data

5.3 Food and Component Coverage and Description

5.4 Components

5.5 Sources of Data and Data Quality

5.6 Biodiversity

5.7 Limitations of Food Composition Data and Their Use

References

Chapter 6: Dietary Reference Values

6.1 Introduction

6.2 Evolution of Dietary Standards, Recommendations and Reference Values

6.3 Principles of Deriving Reference Values

6.4 Uncertainties in Setting Dietary Reference Values

6.5 Critique

References

Chapter 7: Assessment of Physical Activity

7.1 Nutrition, Physical Activity and Public Health

7.2 Physical Activity Definitions

7.3 Validity and Reliability

7.4 Methods to Assess Physical Activity and Sedentary Behaviour

References

Part Two: Current State of Evidence

Chapter 8: Poor Dietary Patterns

8.1 Introduction

8.2 Overview of Current Diets in the UK

8.3 Micronutrient Intakes in Europe

8.4 Food-Based Dietary Guidelines and Tools for Delivering Healthy Eating Advice

8.5 Dietary Patterns and Pattern Analysis

8.6 Conclusions

Acknowledgements

References

Chapter 9: Minerals and Vitamins of Current Concern

Iron

Iodine

Vitamin A

Iron

9.1 Introduction

9.2 Iron Absorption: Intestinal Mucosal Uptake and Transfer of Iron

9.3 Iron and Women in Their Reproductive Years

9.4 Infants and Children

9.5 Dietary Sources of Iron

9.6 Bioavailability of Iron

9.7 Iron Dietary Reference Values

9.8 Causes of Iron Deficiency

9.9 Features of Deficiency

9.10 Anaemia of Chronic Disease

9.11 Measuring Iron Inadequacy, Adequacy and Excess (Status)

9.12 Iron Excess

9.13 Treatment and Prevention of Iron Deficiency

9.14 Addressing Iron Deficiency as a Public Health Issue

9.15 Conclusion

Reference

Iodine

9.16 Introduction

9.17 Iodine Deficiency Disorders

9.18 Conclusions and Recommendations

References

Vitamin A

9.19 Introduction

9.20 History

9.21 Dietary Sources

9.22 Absorption and Transport

9.23 Functions

9.24 Requirements

9.25 Deficiency

9.26 Toxicity

9.27 Assessment of Status

9.28 Special Considerations

9.29 Perspectives on the Future

References

Chapter 10: Nutrition Pre-conception and during Pregnancy

10.1 Introduction

10.2 Nutritional Status Prior to Pregnancy

10.3 Nutritional Requirements During Pregnancy

10.4 Fluid Requirements in Pregnancy

10.5 Vulnerable Groups Within the UK Population

10.6 Diet and Lifestyle Advice for a Healthy Pregnancy

10.7 A Summary of Diet and Lifestyle Recommendations Before and During Pregnancy in the UK

10.8 Improving the Nutrition Status of Women of Childbearing Age

Acknowledgements

References

Chapter 11: Nutrition and Infant/Child Development

11.1 Introduction

11.2 Sources of Information about Infants and Young Children

11.3 Feeding the Infant: Breastfeeding

11.4 Feeding the Infant: Infant Formula

11.5 Feeding the Infant: Complementary Foods

11.6 Feeding the Child Over the Age of 18 Months

11.7 Conclusions

Further Reading

Chapter 12: Nutrition and Teenagers/Young Adults

12.1 Introduction

12.2 Puberty: A Time of Transition into Adulthood

12.3 Diet in Teenagers and Young Adults

12.4 Physical Activity in Teenagers and Young Adults

12.5 Overweight and Obesity in Teenagers and Young Adults

12.6 Bone and Muscle Development during Teenage and Young Adulthood

12.7 Iron Deficiency in Teenagers and Young Adults

12.8 Cognitive Function and Mental Health

12.9 Pregnancy in Teenage and Young Adulthood

12.10 Conclusions

References

Chapter 13: Nutrition in Older Adults

13.1 Introduction

13.2 Associations between Diet and Disease in Older Adults

13.3 Approaches to Nutritional Screening and Assessment

13.4 Challenges to Nutrition in Older Adults

13.5 Conclusion

Disclaimer

References

Part Three: Diet and Disease

Chapter 14: Obesity: Maternal

14.1 Introduction

14.2 Challenges

14.3 Conclusion and Recommendations

References

Chapter 15: Obesity: Childhood

15.1 Introduction

15.2 The Obesogenic Environment

15.3 Genetics

15.4 Parental Influences

15.5 Diagnosis of Childhood Obesity

15.6 Consequences

15.7 Prevention

15.8 Treatment Management

References

Chapter 16: Cardiovascular Diseases: Sodium and Blood Pressure

16.1 Introduction

16.2 Dietary Sodium Intake

16.3 The Evidence on Sodium Intake, Blood Pressure and Cardiovascular Health

16.4 Public Health Strategies to Reduce Population-Wide Sodium Intake

References

Chapter 17: Carbohydrates and Metabolic Health

17.1 Introduction

17.2 Carbohydrate Definitions

17.3 Recommendations on Total Carbohydrate

17.4 Recommendations on Dietary Fibre

17.5 Recommendations on Sugars

17.6 The Carbohydrate Recommendations in Context

References

Chapter 18: Cardiovascular Disease: Dietary Fat Quality

18.1 Introduction

18.2 Relationship between Diet and Plasma Lipid Concentrations

18.3 Atherogenic Lipoprotein Phenotype

18.4 Postprandial Lipids

18.5 Increased Adiposity and Cardiovascular Disease Risk Factors

18.6 Evidence from Cohort Studies and Trials with Clinical Endpoints

18.7 Current Dietary Guidelines

References

Chapter 19: Diet and Cancer

19.1 Global Burden of Cancer

19.2 Aetiology

19.3 Diet, Epigenetics and Cancer

19.4 Early Life Diet and Cancer

19.5 Gut Microbiota as a Modulator of the Effect of Diet on Cancer Risk

19.6 Dietary Recommendations

19.7 Future Research Directions

Acknowledgements

References

Chapter 20: Bone Health

20.1 Introduction

20.2 Definition of Bone Diseases and Public Health Impact of Poor Bone Health

20.3 Fundamentals of Bone Physiology

20.4 Bone Changes Throughout the Life Course

20.5 Diagnosis of Osteoporosis and Assessment of Bone Health

20.6 Regulation of Calcium Homeostasis

20.7 Nutritional Influences on Bone Health

20.8 Concluding Remarks and Areas for Further Research

References

Chapter 21: Dental Health

21.1 Introduction

21.2 Public Health Significance of Oral Diseases

21.3 Diet and Oral Diseases: Overview of the Evidence

21.4 Implications for Action

21.5 Conclusions

References

Chapter 22: Mental Health and Cognitive Function

Iron

Caffeine

B Vitamins

Physical Activity

Iron

22.1 Introduction: Iron Accumulation in the Brain

22.2 Iron Deficiency and Cognitive Development

22.3 Iron and Neurodegeneration

22.4 Summary

References

Caffeine

22.5 Introduction

22.6 Disposition, Metabolism and Physiological Actions of Caffeine

22.7 Psychostimulant Effects of Caffeine

22.8 Motor Performance and Tremor

22.9 Blood Pressure

22.10 Hypertension, Vascular Disease, Stroke and Dementia

22.11 Caffeine Reinforcement, Dependence and Addiction

References

B Vitamins

22.12 Introduction: B Vitamins and the Nervous System

22.13 B Vitamins and Cognitive Development in Early Life

22.14 B Vitamins and Cognitive Function in Ageing

22.15 B Vitamins and Mental Health

22.16 Dealing with Low B Vitamin Status and Related Public Health Challenges

22.17 Conclusions

References

Physical Activity

22.18 Introduction

22.19 Physical Activity and the Prevention of Mental Illness

22.20 Physical Activity and the Treatment of Mental Illness and Disorders

22.21 Psychological Well-Being and Physical Activity

22.22 How do we make a difference?

References

Part Four: Environmental Factors

Chapter 23: Obesogenic Neighbourhood Food Environments

23.1 Introduction to Obesogenic Environments and the Concept of the Food Environment

23.2 Eating Behaviours and how the Food Environment Influences Diet and Obesity

23.3 Defining Spatial Access to Food Outlets

23.4 Urban Planning and Health in the UK

23.5 Conclusions

Acknowledgements

References

Chapter 24: The Wider Environment and its Effect on Dietary Behaviour

24.1 Introduction

24.2 Government-Led Initiatives and Policy

24.3 Income, Price, Marketing, Promotions, Portion Size and Fiscal Strategies

24.4 Cultural-, Environmental- and School-Related Influences

24.5 Social and Health Marketing

24.6 Food Labelling

24.7 Impact of Fortification/Supplementation

24.8 Conclusions

References

Part Five: Public Health Nutrition Strategies and Approaches

Chapter 25: Global and National Public Health Nutrition Approaches

25.1 Introduction

25.2 The Scope for Global Public Health Nutrition Approaches: Global Nutrition Challenges

25.3 Global policy fora discussing public health nutrition

25.4 Role of Non-Government Actors in Nutrition

25.5 Effective Policies and Effective Interventions

25.6 Developing national nutrition policies and programmes

25.7 Conclusions

References

Chapter 26: Developing Strategies in the Community

26.1 Introduction to the Chapter

26.2 Group or Population Approaches

26.3 Individual Approaches

26.4 Omics Approaches (Stratified or ‘Personalised’ Nutrition)

26.5 Overall Conclusion

References

Chapter 27: Dietary Change and Evidence on How to Achieve This

27.1 Introduction to the Chapter

27.2 Behaviour Change Theories and Models

27.3 Strategies Used to Change Dietary Behaviours and Food Intake

27.4 Advantages and Limitations of Individual Approaches and Upstream Approaches

27.5 Conclusions

References

Chapter 28: Evaluation of Public Health Nutrition Interventions and Policies

28.1 Introduction: background

28.2 Evaluation design

28.3 Data collection tools and their validation

28.4 Data analysis and statistics

28.5 Ethical issues

28.6 Recommendations

28.7 Conclusions

References

Chapter 29: Considerations for Evaluation of Public Health Nutrition Interventions in Diverse Communities

29.1 Introduction

29.2 Cultural competency

29.3 Ethnic and cultural diversity

29.4 Literacy

29.5 Evaluation of dietary change in diverse communities

29.6 Conclusion

References

Appendix

Daily Reference Values in the UK

Outside of the UK

References

WHO/FAO data

European data

USA data

Index

End User License Agreement

List of Tables

Table 1.1

Table 2.1

Table 3.1

Table 4.1

Table 4.2

Table 4.3

Table 4.4

Table 5.1

Table 5.2

Table 5.3

Table 6.1

Table 7.1

Table 7.2

Table 8.1

Table 8.2

Table 8.3

Table 8.4

Table 8.5

Table 8.6

Table 8.7

Table 8.8

Table 8.9

Table 9.1

Table 9.2

Table 9.3

Table 9.4

Table 9.5

Table 9.6

Table 9.7

Table 9.8

Table 9.9

Table 9.10

Table 9.11

Table 10.1

Table 10.2

Table 10.3

Table 10.4

Table 10.5

Table 10.6

Table 10.7

Table 10.8

Table 10.9

Table 10.10

Table 10.11

Table 10.12

Table 10.13

Table 10.14

Table 10.15

Table 11.1

Table 11.2

Table 12.1

Table 13.1

Table 13.2

Table 13.3

Table 13.4

Table 13.5

Table 13.6

Table 13.7

Table 15.1

Table 15.2

Table 17.1

Table 17.2

Table 17.3

Table 17.4

Table 17.5

Table 17.6

Table 18.1

Table 19.1

Table 20.1

Table 20.2

Table 21.1

Table 21.2

Table 22.1

Table 23.1

Table 25.1

Table 26.1

Table 26.2

Table 27.1

Table 27.2

Table A.1

Table A.2

Table A.3

List of Illustrations

Figure 1.1

Figure 2.1

Figure 2.2

Figure 2.3

Figure 2.4

Figure 3.1

Figure 4.1

Figure 6.1

Figure 6.2

Figure 6.3

Figure 7.1

Figure 8.1

Figure 8.2

Figure 8.3

Figure 9.1

Figure 9.2

Figure 9.3

Figure 10.1

Figure 10.2

Figure 10.3

Figure 10.4

Figure 10.5

Figure 11.1

Figure 11.2

Figure 11.3

Figure 11.4

Figure 11.5

Figure 11.6

Figure 11.7

Figure 11.8

Figure 11.9

Figure 11.10

Figure 11.11

Figure 11.12

Figure 11.13

Figure 12.1

Figure 12.2

Figure 12.3

Figure 12.4

Figure 12.5

Figure 13.1

Figure 13.2

Figure 15.1

Figure 16.1

Figure 16.2

Figure 16.3

Figure 16.4

Figure 17.1

Figure 17.2

Figure 17.3

Figure 17.4

Figure 18.1

Figure 18.2

Figure 18.3

Figure 18.4

Figure 20.1

Figure 20.2

Figure 21.1

Figure 21.2

Figure 21.3

Figure 21.4

Figure 21.5

Figure 23.1

Figure 23.2

Figure 23.3

Figure 23.4

Figure 24.1

Figure 24.2

Figure 24.3

Figure 25.1

Figure 25.2

Figure 26.1

Figure 27.1

Figure 27.2

Figure 27.3

Figure A.1

Guide

Cover

Table of Contents

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The Nutrition Society Textbook Series

Now widely adopted in courses throughout the world, the prestigious Nutrition Society Textbook Series provides students with both specific scientific information and appropriate context.

These groundbreaking titles:

Provide students with the required scientific basics of nutrition in the context of a systems and health approach

Enable teachers and students to explore the core principles of nutrition, to apply these throughout their training, and to foster critical thinking at all times

Are fully peer reviewed, to ensure completeness and clarity of content, as well as to ensure that each book takes a global perspective.

Nutrition Research Methodologies

Edited by Lovegrove, Hodson, Sharma & Lanham-New

March 2015

ISBN: 978-1-118-55467-8

Clinical Nutrition, 2nd Edition

Edited by Elia, Ljungqvist, Stratton & Lanham-New

January 2013

ISBN: 978-1-4051-6810-6

Sport and Exercise Nutrition

Edited by Lanham-New, Stear, Shirreffs & Collins

October 2011

ISBN: 978-1-4443-3468-5

Nutrition and Metabolism, 2nd Edition

Edited by Lanham-New, MacDonald & Roche

November 2010

ISBN: 978-1-4051-6808-3

Introduction to Human Nutrition, 2nd Edition

Edited by Gibney, Lanham-New, Cassidy & Vorster

March 2009

ISBN: 978-1-4051-6807-6

Public Health Nutrition

Second Edition

Edited on behalf of The Nutrition Society by

Professor Judith L Buttriss

Director General, British Nutrition Foundation

Dr Ailsa A Welch

Reader in Nutritional Epidemiology, University of East Anglia

Dr John M Kearney

Lecturer, Epidemiology, Dublin Institute of Technology

Editor-in-Chief

Professor Susan A Lanham-New

Head of the Department of Nutritional Sciences, University of Surrey

This edition first published 2018 © 2018 by The Nutrition Society.

Edition History 1e © The Nutrition Society 2004.

Registered office:

John Wiley & Sons, Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK

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All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher.

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Library of Congress Cataloging-in-Publication Data

Names: Buttriss, Judith L, editor. | Welch, Ailsa A, editor. | Kearney, John M., editor. | Lanham-New, Susan A, Editor-in-Chief. | The Nutrition Society (Great Britain), Issuing Body.

Title: Public Health Nutrition / edited on behalf of The Nutrition Society by Judith L. Buttriss, Ailsa A. Welch, John M. Kearney, Susan A. Lanham-New.

Other titles: Public Health Nutrition (The Nutrition Society (Great Britain))

Description: Second edition. | Chichester, West Sussex, UK ; Ames, Iowa, USA : John Wiley & Sons, Inc., 2017. | Includes bibliographical references and index.

Identifiers: LCCN 2016056644| ISBN 9781118660973 (paper) | ISBN 9781118660935 (Adobe PDF) | ISBN 9781118660966 (epub)

Subjects: | MESH: Nutritional Physiological Phenomena | Dietetics | Public Health

Classification: LCC RA645.N87 | NLM QU 145 | DDC 616.3/9—dc23 LC record available at https://lccn.loc.gov/2016056644

A catalogue record for this book is available from the British Library.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Cover image: © skystardream/iStockphoto

Contributors

Professor Peter J Aggett

Lancaster University

UK

Dr Sarah C Bath

University of Surrey

UK

Bridget Benelam

British Nutrition Foundation

UK

Dr Francesco Branca

World Health Organization

Switzerland

Professor Eric J Brunner

University College London

UK

Dr Thomas Burgoine

University of Cambridge

UK

Professor Judith L Buttriss

British Nutrition Foundation

UK

Professor Janet E Cade

University of Leeds

UK

Dr U. Ruth Charrondiere

Food and Agriculture Organization of the United Nations

Italy

Dr Clare A Corish

University College Dublin

Ireland

Dr Andrea L Darling

University of Surrey

UK

Johanna T Dwyer

Tufts University

USA

Professor Ulf Ekelund

Norwegian School of Sport Sciences (NIH)

Norway

Professor Basma Ellahi

University of Chester

UK

Professor Paul Elliott

Imperial College London

UK

Cassandra H Ellis

The Nutrition Society

UK

Dr Charlotte EL Evans

University of Leeds

UK

Paul Finglas

Institute of Food Research

UK

Dr Emma Foster

Newcastle University

UK

Professor Kenneth R. Fox

University of Bristol

UK

Dr Christine Furber

The University of Manchester

UK

Jenny Gillespie

NHS Tayside

UK

Dr Bjørge H Hansen

Norwegian School of Sport Sciences (NIH)

Norway

Dr Richard PG Hayhoe

University of East Anglia

UK

Dr Anja Heilmann

University College London

UK

Dr Jayne Hutchinson

University of Leeds

UK

Elizabeth J Johnson

Tufts University

USA

Ashley T LaBrier

Tufts University

USA

Dr Amelia A Lake

Durham University

UK

Professor Susan A Lanham-New

University of Surrey

UK

Professor Alison M Lennox

University of Surrey

UK

Professor H David McCarthy

London Metropolitan University

UK

Professor Helene McNulty

Ulster University

UK

Dr Tracey A Mills

The University of Manchester

UK

Dr Emily Mohn

Tufts University

USA

Dr Farah Naja

American University of Beirut

Lebanon

Dr Lara Nasreddine

American University of Beirut

Lebanon

Dr Anne P Nugent

University College Dublin

Ireland

Dr Marga Ocke

National Institute for Public Health and the Environment

Netherlands

Dr Linda M Oude Griep

Imperial College London

UK

Jenny Plumb

Institute of Food Research

UK

Professor Margaret P Rayman

University of Surrey

UK

Mark Roe

Institute of Food Research

UK

Professor Peter J Rogers

University of Bristol

UK

Professor Tom Sanders

Kings College London

UK

Dr Paul A Sharp

Kings College London

UK

Dr Debbie M Smith

The University of Manchester

UK

Dr Sara Stanner

British Nutrition Foundation

UK

Dr Laura Stewart

NHS Tayside

UK

Professor Janice L Thompson

University of Birmingham

UK

Professor Tim G Townshend

Newcastle University

UK

Professor Richard G Watt

University College London

UK

Dr Elisabeth Weichselbaum

Nutrition Science and Consultancy

New Zealand

Dr Ailsa A Welch

University of East Anglia

UK

Dr Louise R Wilson

University of Surrey

UK

Professor Martin Wiseman

World Cancer Research Fund & University of Southampton

UK

Taryn Young

NHS Tayside

UK

As Patron of the British Nutrition Foundation I am pleased to contribute the Foreword for this comprehensive new edition of a popular textbook on Public Health Nutrition. Much has changed in the world of nutrition since the first edition was published in 2004, especially through confusing headlines and specialist research that seemed to contradict each other. The aim of the editorial team for the second edition, led by Professor Judith Buttriss from the British Nutrition Foundation, has been to bring the book up to date and, at the same time, to meet the requirements of students of nutrition and practitioners, as well as try to balance all that information. The book provides the reader with a comprehensive series of chapters in five themed sections, covering basic principles through to practical application of public health nutrition in local, national and international settings, and its translation into policy.

The Nutrition Society textbook series, first established by Professor Michael Gibney in 1998 and now under the direction of the second Editor-in-Chief, Professor Susan Lanham-New, continues to be an extraordinarily successful venture for the Society. This series of human nutrition textbooks is designed for use worldwide and this has been achieved by translating the series into many different languages including Spanish, Greek and Portuguese. The popularity of the textbooks is a tribute to the quality of the authorship and the value placed on them, both in the UK and Worldwide, as a core educational tool. I am sure this textbook will make a very valuable contribution to the Nutrition debate. Perhaps I might suggest a strapline: all things in moderation!

Preface

I am absolutely delighted in my capacity as Editor-in-Chief (E-i-C) of the Nutrition Society (NS) Textbook Series to introduce the Second Edition of Public Health Nutrition. So much planning and hard work has gone into producing this Second Edition, following a most successful production of Public Health Nutrition First Edition. We owe a great deal of thanks to Professor Barrie Margetts, Professor Lenore Arab and Dr John Kearney for their original work on this important book in the NS Textbook Series.

Public Health Nutrition 2nd Edition (PHN2e) has been led superbly by Professor Judith Buttriss (Director General, British Nutrition Foundation) as Senior Editor of the book, and her Editorial Team in the name of Dr Ailsa Welch (University of East Anglia) and Dr John Kearney (Dublin Institute of Technology). They have meticulously planned out the details of the chapters and managed to secure the world-leaders in the field to contribute key chapters. Professor Buttriss is a most inspirational leader, and the team have complemented one another admirably with their expertise and knowledge in the field, as well as providing great continuity from the First Edition. How indebted we are to all the contributors for making the book such a comprehensive review and we are absolutely thrilled, as Professor Buttriss outlines in her Introductory Chapter, to have so many global experts who have written chapters to make PHN2e a complete review of this key area.

PHN2e is intended for those with an interest in nutritional science whether they are nutritionists, food scientists, dietitians, medics, nursing staff or other allied health professionals. We hope that both undergraduate and postgraduate students will find the book of great help with their respective studies and that the book will really put public health nutrition as a discipline into context.

PHN2e comprises of a total 29 chapters; commencing with a detailed overview of the book structure and then a focus of five sections; namely: 1) Public Health Nutrition Tools; 2) Current State of Evidence; 3) Diet and Disease; 4) Environmental Factors and 5) Public Health Nutrition Strategies and Approaches, with each chapter providing a key summary of the take home messages.

We are extremely honoured and most sincerely grateful that the Foreword for PHE2e has been written by Her Royal Highness The Princess Royal, who has a great depth of knowledge in the field and who speaks with authority on key issues in Public health Nutrition. It gives us great confidence in this textbook to have such a Royal seal of approval.

The first and second textbooks in the Series: Introduction to Human Nutrition (IHN) and Nutrition & Metabolism (N&M), are now out in 2nd Edition and sales continue to go extremely well, with third editions now fully under-preparation. Sales of Professor Marinos Elia et al's Clinical Nutrition 2nd Edition (CN2e - fourth textbook) continue to sell apace and our fifth textbook in the Series, Sport and Exercise Nutrition 1st Edition (SEN1e) has surpassed all expectations. Our sixth textbook, Nutrition Research Methodology 1st Edition (NRM1e) led by Professor Julie Lovegrove et al provides great complementarity to PHN2e, and the Series, and is proving to be an excellent textbook in its own right.

We are most grateful to the following individuals for their support and most generous Forewords in SEN1e, CN2e and NRM1e respectively; namely - Professor Richard Budgett OBE, Chief Medical Officer for the London 2012 Olympic and Paralympic Games and now Medical and Scientific Director at the International Olympic Committee (IOC) based in Lausanne, Switzerland; Dame Sally Davies, Chief Medical Officer (CMO) for England, and the UK Government's Principal Medical Adviser; Professor Lord John Krebs, Principal, Jesus College, University of Oxford and our first Chairman of the UK Food Standards Agency.

The Society is most grateful to the textbook publishers, Wiley-Blackwell for their continued help with the production of the textbook and in particular, James Watson, Jennifer Seward and Francesca Giovannetti. We would also like to thank Garima Singh from Thomson Digital for her great help with PHN2e finalisation. In addition, I would like to acknowledge formally my great personal appreciation to Professor G.Q. Max Lu AO, FRSC, FIChemE, Vice-Chancellor of the University of Surrey, and Professor David Blackbourn FRSB, Head of the School of Bioscience and Medicine, University of Surrey, for their respective great encouragement of the nutritional sciences field in general, and the Textbook Series production in particular.

Sincerest appreciation indeed to the Nutrition Society past-Presidents, Professor Sean J.J. Strain OBE (Ulster University) and Professor Catherine Geissler (King's College London) and current-President, Professor Philip Calder (University of Southampton) for their belief in the Textbook Series. With special thanks to past-Honorary Publications Officer, Professor David Bender (University College London), and present-Honorary Publications Officer Professor Paul Trayhurn (University of Liverpool) for being such tremendous sounding boards for the Textbook Series. I am hugely grateful for their wise counsel. And finally a very big thank you indeed to Cassandra Ellis, Assistant Editor, NS Textbook Series, for her incredibly important contribution to the development of the Series.

Finally, as I always write and absolutely do not forget (ever!), the Series is indebted to the forward thinking focus that Professor Michael Gibney (University College Dublin) had at that time of the Textbook Series development. It remains such a tremendous privilege for me to continue to follow in his footsteps as the second E-i-C.

I really hope that you will find the textbook a great resource of information and inspiration…please enjoy, and with so many grateful thanks to all those who made it happen!

With my warmest of wishes indeed

Professor Susan A Lanham-New RNutr, FAfN FRSB

E-i-C, Nutrition Society Textbook Series and Head, Department of Nutritional Sciences School of Biosciences and Medicine, Faculty of Health and Medical Sciences University of Surrey

Introduction

Much has changed in the 12 years since the launch of the first edition of Public Health Nutrition. With an explosion of research in this area, changes in nutrition policy and food-related legislation, and shifts in population health, dietary patterns and the food supply, the second edition represents a complete rewrite. We are honoured to have so many global experts in public health nutrition (PHN) contributing to make this textbook a comprehensive review.

To ensure the second edition reflects the most recent knowledge and research, and meets the requirements of students and practitioners alike, an expert advisory group was consulted throughout the planning process. The group members, representing research, teaching and PHN practice, were asked to comment on the content and structure of the new edition, and to provide guidance on what they were looking for in a PHN resource.

The textbook not only introduces PHN concepts, it is also intended to support learning for students and to be a practical guide for health professionals and those working within public health. More generally, feedback highlighted the benefit of including case studies to illustrate the practical application of the evidence and how this translates to policy. Case studies have therefore been included throughout to support the evidence and to offer practical advice for those working within PHN.

The clear message throughout consultation was the importance of structure and flow through the textbook. To ensure a clear, concise structure, the 29 chapters have been divided into clearly defined sections covering five key areas of PHN.

Part One outlines PHN assessment tools. This provides an introduction to concepts in PHN, followed by an overview of dietary assessment methodology, anthropometry and physical activity measures, with a focus on contemporary measures using new technology as well as traditional methods. This part then outlines the importance of food composition data in nutrition research, food safety and food security, and discusses dietary guidelines.

Part Two moves on to considering the application of PHN tools in a review of the current evidence. It begins by outlining dietary patterns and how they are defined before discussing vitamins and minerals that are of particular concern due to prevalent deficiency. This part also examines nutrition through the lifecycle, from pre-conception to old age, considering the public health challenges and risk factors at each phase.

Part Three reviews the relationship between diet and disease. Beginning with the risks of obesity in pregnancy and childhood, chapters that follow discuss some of the comorbidities of obesity, cardiovascular disease and type 2 diabetes. The relationship between diet and cancer is also examined, with consideration to both the protective and the carcinogenic roles of dietary factors. The PHN challenges associated with bone and dental health are also reviewed, and the relationship between diet and mental health and cognitive function is explored.

Part Four looks at the impact of environmental factors on public health, starting with consideration of the effects that obesogenic environments have on diets and health. Also explored is how aspects such as advertising, health promotion, food reformulation and food legislation can affect dietary behaviours.

Finally, Part Five outlines current public health strategies, policies and approaches. It begins broadly with a global perspective, before considering community strategies and engagement, how these strategies can be used to influence behaviour change, and the importance of culturally sensitive interventions and policies. The final chapters provides an evaluation of current policies and interventions and the social determinants of diet and health.

Judith L Buttriss

About the Companion Website

This book is accompanied by a companion website:

www.wiley.com/go/buttriss/publichealth

The website includes:

Multiple choice questions

Short answer questions

Essay titles

Further readings

Part OnePublic Health Nutrition Tools

1Introduction to Public Health Nutrition

Martin Wiseman

Key Messages

Nutrition is fundamental for life and health. The term ‘nutrition’ encompasses both biological and sociological aspects of how cells, tissues and organisms access the substrates and cofactors that are necessary for normal conception, growth, development and ageing.

Public health nutrition refers to nutritional aspects of public health, which is the science and art of promoting and protecting health and well-being, preventing ill health and prolonging life through the organised efforts of society.

The historical focus of public health nutrition has been on undernutrition, which is still a major problem across all levels of development. In less economically developed countries, it most commonly manifest as deficiencies of micronutrients as well as wasting and stunting (acute and chronic malnutrition) in childhood. In economically developed countries undernutrition is a common feature of ageing, though nutrition-related chronic non-communicable diseases such as obesity, type 2 diabetes, cardiovascular disease and several common cancers predominate. Increasingly, as less economically developed countries undergo nutritional transition, they are experiencing a rising burden of these diseases, so that these are now the major nutrition-related disease burden globally.

The characterisation of human nutrient requirements is a fundamental activity for public health nutrition, and their application in clinical or public health settings requires training and experience that marks professional nutritional practice.

Effective public health nutrition requires three discrete functions

the acquisition, synthesis and dissemination of knowledge relating nutrition to health and disease;

surveillance programmes to detect potential nutritional problems across the life course among the population, and to monitor change;

evidence-informed policy development, implementation and evaluation.

Public health nutrition policy relies on ensuring that people have the necessary information to make healthy choices around food and physical activity, as well as on ensuring that the environment in which they live is conducive to making those healthy choices. Policy makers need to balance the evidence for health need against economic and other socio-political factors in determining what action to take.

1.1 Public Health and Nutrition

Nutrition lies at the heart of health. Human life – from conception or even before, through fetal and childhood growth, development and maturation, to adult life and old age – creates a demand for energy and nutrients, and relies on their adequate provision, and on the body's metabolic capability to transform these substrates and cofactors into the multitude of chemicals needed by cells for normal structure and function, driven by their genetic endowment. Nutrition is the process by which cells, tissues, organs, people and populations achieve this. Poor nutrition leads to poor health; and poor health also often leads to poor nutrition.

Public health refers to those aspects of health that affect the population as a whole, their study and the services that aim to deliver it. Public health nutrition is where these two concerns – population health and nutrition – interact or overlap.

Public health is defined as ‘The science and art of promoting and protecting health and well-being, preventing ill health and prolonging life through the organised efforts of society’.

It is worth elaborating on that concise definition, first to note the implicit recognition that the evidence (science) underpinning actions to promote or protect health may often be incomplete, and that professional judgement (art) is needed to interpret and apply it. This is no different in concept from the application of science in clinical care, where the demand for evidence-based practice exposes gaps in knowledge of how to manage the very variable presentations of individual patients, but does not paralyse clinical action. Second, it is important that prolongation of life is linked with the promotion of health and prevention of ill health, in order to avoid prolonged disability with ageing. The aim is to shorten the period of ill health (compression of morbidity) before death in old age. Third, public health needs to be organised. It is not a default, as can be seen in the many parts of the world where effective public health structures and systems do not exist, and where infant and maternal mortality are high, expectation of life is low, and infectious and increasingly non-communicable diseases are common, as was the case in now economically developed countries in the past. Finally, the responsibility to make efforts falls not only to the small group of people who are professionals in public health, but to society as a whole. This recognises that the determinants of health in populations have little to do with the health care system (which deals with the problems of failed health), and are mostly related to the wider environmental conditions in which people are conceived, born, grow, live, work and age. Public health is about creating environments that are conducive to health, and public health nutrition is about creating environments that are conducive to healthy nutrition.

1.2 History of Nutrition in Public Health

The ancients regarded food and medicine as related aspects, and since the demonstration in the 18th century by James Lind that lime juice was effective in curing and preventing scurvy (even though the finding was initially ignored and later had to be rediscovered), it has been clear that the provision of appropriate quality and quantity of food is essential in securing people's health.

The importance of food for growth, development and health was apparent despite lack of knowledge of the biological processes involved. This ignorance of the detail of the body's nutritional demands and how different foods and diets can meet them meant that it was difficult to derive rational nutrition policies.

The UK offers a good illustration. In the UK during the First World War, disruption to food imports from abroad had a major impact on the food supply (see Table 1.1), but there was insufficient understanding of the nutritional consequences for a coherent political response to be mounted.

Table 1.1 When food imports were seriously disrupted in the First World War (WW1), limited nutrition knowledge meant that a coherent food policy was not possible and the food supply was adversely affected. In contrast, despite similar disruption to food imports in the Second World War (WW2), the application of the new nutritional science into effective policy ensured that the food supply was maintained and equitably distributed to secure the health of the population.

Source: Magee (1946). Reproduced with permission of BMJ Publishing Ltd.

WW1

WW2

Milk

−26%

+28%

Eggs

−40%

−6%

Meat

−27%

−21%

Vegetables

−9%

+34%

Subsequently, the British population experienced food shortages, and malnutrition was a major problem. After the establishment of the Ministry of Health in 1919, food and nutrition were early targets for a more systematic approach to policy. In 1921 the Ministry published a report on ‘Diet in Relation to Normal Nutrition’ that identified the importance of so-called ‘protective foods’ – green leafy vegetables, milk and eggs – for healthy growth in children. This period coincided with the explosion of nutrition research into the accessory food factors (vitamins, minerals and trace elements) and the biological mechanisms for their effects – a discipline which spawned the new word ‘biochemistry’. By the time of the Second World War, when there was a similar disruption as in the first war to the food imports on which the British food supply depended, nutritional science had progressed sufficiently for the Government to base its food policy on sound science. This policy, which involved public education with enhanced local food production and controls on the equitable distribution of food, led to quite different effects on the food supply (see Table 1.1), and its success to the British Ministries of Food and Health later receiving the prestigious Lasker Award for public health.

This period set the foundations for the essential elements of food and nutrition policy into the future. The key aspects are

a transparent mechanism for the provision of scientific nutrition advice to government;

reliable means for monitoring diet and nutrition status among the population;

effective means of developing and evaluating policies to assure the quality and quantity of the food supply, and the nutritional health of the population.

The most prominent aspect of nutritional advice was the establishment by groups of experts of so-called recommended daily (or dietary) allowances. These set the amounts of essential nutrients needed to be consumed by populations to minimise risk of deficiencies, based on the growing science. These reports, published in the UK in the same series as the 1921 report for the Ministry of Health, have now been supplanted in most countries, following the UK 1991 report on dietary reference values, by attempts to describe the estimated range of dietary requirements for different nutrients among populations, including the balance of macronutrients considered desirable to reduce risk of chronic disease.

The establishment in Britain in 1940 of the National Food Survey was the forerunner of a systematic programme of diet and nutrition surveys which characterise the food and drink consumption of the population from childhood to old age, as well as their nutrition status in terms of anthropometry and biochemical measurements of blood and urine, and relevant physiological measures such as blood pressure. Such food and health monitoring systems play an essential role in the detection of nutritional problems in the population, tracking their development, and evaluating the effectiveness of policies to address them.

The success of the wartime food policy in the UK may in part be ascribed to the possibility of applying stringent controls and restrictions on the national diet due to the national emergency, as well as the coincidentally high levels of physical activity that were prevalent at the time. However, such restrictive approaches, though effective, are unlikely to find favour beyond the stringent circumstances of such an emergency, and a critical issue for policy makers is to find effective means of promoting healthy nutrition without inappropriate interference with people's freedom to choose how they live. This dilemma has been addressed by various commentators, including the Nuffield Council on Bioethics.

1.3 Nutrition and Public Health in Different Parts of the World

For the majority of the 20th century, nutrition policy in industrialised countries was directed to the elimination of classic micronutrient deficiency diseases such as scurvy and rickets, which were major scourges in particular among the least affluent in society. In less economically developed countries, gross malnutrition with wasting and stunting of children, and high levels of maternal and child mortality, as well as specific nutrient deficiencies, remain common, mirroring the situation of the previous century in industrialised countries.

During the latter part of the 20th century and in the 21st century, the prominence in economically developed countries of deficiency diseases diminished with better access for all to a wide variety of foods, and effective food fortification policies. However, this was replaced by a growing burden of chronic non-communicable disease, at first cardiovascular disease, but increasingly cancers, obesity and diabetes. At the same time, some micronutrient deficiencies – in particular rickets – began to re-emerge, while undernutrition in the ageing population has become an important concern, sometimes simply due to poor dietary intake (with low lean mass and activity levels), and sometimes consequent to disease.

In less economically developed countries, the problems of malnutrition with stunting and wasting continue to dominate, but as the populations undergo an economic transition from rural to more urbanised ways of life, they also undergo a nutrition transition so that rates of obesity, and other chronic non-communicable diseases, are also rising, creating the so-called double burden (of over– and undernutrition). In places such as Thailand and Chile, which have had tangible success in reducing undernutrition, this has been at the cost of a rise in prevalence of overweight and obesity.

Clearly, malnutrition in all its forms affects all parts of the globe, though its segmentation within society varies.

1.4 Current Role of Nutrition in Public Health

Socio-demographic changes are affecting many parts of the globe. In most countries people are living longer, while economic development is also driving increased urbanisation, with rapid and profound changes in ways of life. In more affluent countries, average smoking rates are declining, while prevalence of overweight and obesity are increasing, and levels of physical activity have fallen. Traditional diets are being replaced by typical ‘westernised’ patterns, with more processed foods including fats, oils, refined starches and sugars, higher salt intake and a greater reliance on foods from animal as opposed to plant sources.

In less economically developed countries there is a rising burden of cardiovascular disease, and increasingly also the cancers more typical of affluent nations – breast, colorectal and prostate – related to nutritional factors, in place of the cancers caused by infections – liver, stomach and cervix. Lung cancer remains a scourge – though mostly of men – as smoking rates have not declined as in more affluent countries, and indeed are still rising in some.

In more affluent nations, rates of cardiovascular disease are declining, so that with increasing age the major non-communicable disease group is predicted to be cancers, many of which are related to dietary patterns, body fatness and physical activity levels.

Meanwhile malnutrition – stunting and wasting in children, short stature in adulthood, as well as specific micronutrient deficiencies – remains prevalent, often within the same communities as increasing overweight and obesity. Even in richer countries, where food security is less of a problem, micronutrient deficiencies such as rickets remain persistent in vulnerable groups, and are possibly increasing.

1.5 Nutrition Through the Life Course

Nutritional problems have always been recognised at all stages of the life course. Maternal overweight or obesity, or underweight, are known to influence the outcome of pregnancy both for the mother and the infant. Low birth weight remains a problem among low-income countries, and nutritional factors are key. Poor growth with wasting and stunting are classic nutritional problems of undernutrition, which remain prevalent in low income countries, while increasingly in high income countries obesity is becoming a serious problem in childhood. One consequence of the nutrition transition is the development of a cohort of people of short stature from undernutrition in childhood, but who then become overweight or obese; this combination carries enhanced risk for nutrition-related problems, in particular for maternal and fetal outcomes in pregnancy. Adolescence is a period of rapid growth and development, with increased demands for energy and nutrients, and so is a period of vulnerability to any constraint on supply, and this can be compounded by early pregnancy, which drives competing demands between mother and fetus. Micronutrient deficiencies remain prevalent where food supply is monotonous and insecure, emphasising the need for dietary diversity, while adult obesity with its attendant co-morbidities of diabetes, cardiovascular disease and some cancers is a major problem for high-income countries and increasingly so for middle– and even low-income countries. Undernutrition is also becoming an important cause of morbidity and mortality among older people.

There is growing recognition of the impact of nutrition not only in the immediate context, but as a determinant of future health. Non-communicable chronic diseases such as obesity, diabetes, cardiovascular disease and cancers result from the interaction of people's current exposures – their diet, activity levels and nutritional state – with their susceptibility. Susceptibility is partly determined by genetic endowment; however, it is now clear that early life events (in particular constraint of growth due to imbalance between the amount or quality of the demands for energy or nutrients, and their supply, from conception to adulthood) can have a profound impact on later risk of these conditions.

1.6 Principles of Public Health Nutrition

Effective public health nutrition requires three discrete functions

the acquisition, synthesis and dissemination of knowledge relating nutrition to health and disease;

surveillance programmes to detect potential nutritional problems across the life course among the population, and to monitor change;

evidence-informed policy development and implementation.

The primary prevention of disease relies on the identification of the causes of disease, so that they may be addressed. The identification of infectious causes has led to the development of vaccination and antibiotics, and of means to control their vectors, such as the mosquito for malaria. The identification of a deficiency of the essential nutrients allowed for dietary approaches to their prevention, and policies such as food fortification. For nutrition-related chronic non-communicable diseases, with multiple causes and highly variable susceptibility in the population, not only is the identification and characterisation of the pathways of causation complex, but equally the appropriate medical, public health or political response is often difficult to agree. Nevertheless, an analogous approach to these problems allows an open dialogue on how to address them.

It is essential that any approach relies on the whole body of scientific evidence. As in all health practice, this may be epidemiological information, clinical trial data or laboratory evidence, or less reliable forms. In clinical medicine, randomised controlled trials (RCTs) are rightly regarded as superior to other forms of investigation because of their ability to test relevant hypotheses with a robust design and avoid the problems of confounding that arise in epidemiological studies. However, for primary prevention of chronic non-communicable disease that manifests in adulthood but has roots in early life, and where the impact of environmental exposures takes decades, it is less clear that RCTs have net overall advantage. While well-designed and –executed RCTs have strong internal validity (they give a correct answer to the hypothesis tested), they often lack external validity (that is, they cannot test the right hypothesis) perhaps because they are not conducted in an appropriate population or use atypical exposures. For primary prevention, intelligent interrogation of the whole body of evidence is required to infer causation from observed associations. This can be aided by using accepted frameworks such as that derived by Bradford Hill. Such synthetic approaches to the evidence can identify preferred patterns of diet or lifestyle likely to reduce disease and promote health.

Once such patterns are identified, it is important to explore to what extent they are present in the population, and in potentially vulnerable subgroups. For this reason, proactive nutritional surveillance of the population is a necessary component of rational public health nutrition. Such monitoring surveys may identify the prevalence of disease risk factors in the population such as obesity or physical inactivity, or of biological factors such as high blood pressure or disordered blood lipids. They also allow the impact of policy to be evaluated.

Vulnerable subgroups may be defined in several ways. They are often defined in terms of age, sex, ethnicity or socio-economic state. However, it is equally possible to conceive vulnerability from a biological perspective. Diet and health surveys allow the distribution of relevant variables (such as risk factors or markers of nutritional status) within the population to be calculated. Though one aim of policy is to shift the whole distribution of risk in a population in a beneficial direction, interest – aided by newer technologies – is increasingly being paid to exploring the variability itself. Such variability reflects individual characteristics that determine susceptibility (e.g. to disease), and characterising the risks of individuals within the population and their determinants (as well as the determinants of differential risk between populations, which may be different) is an increasing focus of attention. For example, fortification of staple foods with folic acid has been proposed (and in some countries implemented) to ensure adequate intake in women who become pregnant to reduce the risk of neural tube defects in their offspring. However, there are concerns that such broad exposure to fortified foods might lead to excessive intakes among those who already have high intakes, emphasising the need to consider the shape of the distribution of intake, and not only the average.

Finally, effective public health action requires the development of policies based on the evidence. Though seemingly obvious, much nutrition policy may nevertheless be based on preconceptions or ideological preferences. Because the evidence for effectiveness of policy is difficult to obtain by conventional medical models of investigation, policy needs first to identify the nutritional problems that need addressing; to develop policies based on the best evidence available (even if incomplete) and implement them in a way that can be evaluated to allow the policy to be continuously improved (that is, to develop evidence from the evaluation of policies in action). Because policy often involves politics, and the solution needs to embrace not only the health aspects but also socio-political considerations, tensions may arise in identifying the appropriate intervention or its degree. This aspect has been addressed by the Nuffield Council on Bioethics, which developed a ‘ladder’ of different degrees of intervention as a framework for consideration (Figure 1.1). While this ladder offers a valuable framework, it is predicated on relatively simple, single actions. This limits its practical use in public health, which has the characteristics of a complex system. Failure to recognise the inherent complexity in the determinants of people's behaviour may in part be responsible for the relatively modest effects observed from many more linear interventions, as well as unwillingness to adopt policies that are more restrictive.

Figure 1.1 The intervention ladder. Source: Nuffield Council on Bioethics (2007). Reproduced with permission of Nuffield Council on Bioethics.