the role of appetite in regulating the quality and quantity of children's dietary intake

438 Pages·2016·6.44 MB·English

THE RELATIONSHIP BETWEEN APPETITIVE TRAITS,
DIETARY INTAKE AND WEIGHT GAIN IN THE GEMINI
COHORT

Hayley Syrad

A thesis submitted for the degree of Doctor of Behavioural
Nutrition
UCL

1
DECLARATION

I, Hayley Syrad confirm that the work presented in this thesis is my own. Where
information has been derived from other sources, I confirm that this has been
indicated in the text and acknowledgements.

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ACKNOWLEDGEMENTS

I would first like to express my gratitude to the late Jane Wardle for providing me
with the opportunity to work on this project. Her expertise and guidance helped to
shape my work into something I am incredibly proud of and she inspired me
enormously. I also must thank Clare Llewellyn for her support and encouragement
throughout. Her intellectual ability and insight, coupled with her light-hearted, bubbly
and warm personality made for a fantastic supervisor. Thank you also to Ellen van
Jaarsveld who saw me off on this journey back in 2012, and David Boniface for
dedicating his time to help me with statistics. Thank you also to Laura Johnson for
making me think outside of the box. I am privileged to have had invaluable input
from Susan Jebb during this process, and Alison Fildes has offered a fresh
perspective on my work.

I have a number of friends at the HBRC whom I wish to thank for making it a joy to
come into work, especially my fellow PhD students. This work would also not have
been possible without the Gemini families completing questionnaires and food
diaries; I am extremely grateful for the time they have taken over the years to remain
involved in the Gemini study. I would also like to acknowledge the Human Nutrition
Research Unit for analysing the dietary data, and the Medical Research Council,
Nutricia Ltd, and UCL for their financial and administrative support.

I must of course mention the office mascot; my dog Pepper, for making me laugh
every day and making the PhD room a happier place. Rob - thank you for the fun,
love and laughter, and for making the final stages of my PhD such a happy time.
Finally, thank you to my wonderful family. My Dad recently said “you know we will
always support you in whatever ventures you embark on” and without their never-
ending emotional (and financial!!) support I could not have done this. I will forever be
grateful.

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TABLE OF CONTENTS

ABSTRACT ............................................................................................................ 13
LIST OF TABLES .................................................................................................. 14
LIST OF FIGURES ................................................................................................ 17
LIST OF APPENDICES .......................................................................................... 18
CHAPTER 1. APPETITE, DIETARY INTAKE AND WEIGHT GAIN IN EARLY
LIFE: A REVIEW OF THE LITERATURE ............................................................... 20
1.1 Weight gain in early life ................................................................................. 20
1.1.1 Risk factors for childhood obesity ....................................................... 21
1.2 Appetite and childhood weight ....................................................................... 24
1.2.1 Measuring appetite in children ............................................................. 25
1.2.1.1 Behavioural methods .................................................................. 25
1.2.1.1.1 Limitations of behavioural studies in children .................... 27
1.2.1.2 Psychometric methods .............................................................. 27
1.2.1.2.1 Dutch Eating Behaviour Questionnaire (DEBQ) ................ 28
1.2.1.2.2 Child Eating Behaviour Questionnaire (CEBQ) ................. 28
1.2.2 Current evidence for associations between appetite and weight in
children ............................................................................................................... 29
1.2.2.1 Behavioural evidence ................................................................. 29
1.2.2.1.1 Food cue reactivity and weight .......................................... 29
1.2.2.1.2 Eating in the absence of hunger and weight...................... 30
1.2.2.1.3 Energy compensation and weight ..................................... 32
1.2.2.2 Psychometric evidence ............................................................... 33
1.3 Appetite and eating behaviour ....................................................................... 37
1.3.1 Measuring dietary intake in children .................................................... 38
1.3.1.1 Food Frequency Questionnaires ................................................ 38
1.3.1.2 24 hour dietary recall ................................................................. 39
1.3.1.3 Doubly Labelled Water (DLW) ................................................... 39
1.3.1.4 Diet diaries................................................................................. 40
1.3.1.5 Evaluation of dietary assessment methods ................................ 40
1.3.2 Defining meal patterns ......................................................................... 41
1.3.3 Current evidence for associations between appetite and eating
patterns.. ............................................................................................................. 42
1.4 The role of eating patterns in childhood weight .............................................. 45
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1.4.1 Current evidence for associations between meal frequency and
childhood weight ................................................................................................. 47
1.4.2 Current evidence for associations between meal size and childhood
weight ................................................................................................................. 51
1.4.3 The interplay between meal size and frequency and effects on energy
intake .................................................................................................................. 55
1.4.4 The relative role of meal size and meal frequency in weight gain ........ 57
1.5 Current evidence for the continuity and stability of weight, appetite and eating
patterns in children .............................................................................................. 58
1.6 Conclusions and future research ................................................................... 59

CHAPTER 2. RESEARCH AIMS OF THE CURRENT THESIS ............................. 60
2.1 Aims and outline of the research in the current thesis ................................... 60
2.1.1 Dietary intakes of young children in the UK ......................................... 63
2.1.2 The role of appetite in formula milk and food intake in early life ........... 63
2.1.3 Appetitive traits and eating patterns in early life ................................... 64
2.1.4 Eating patterns in early life and adiposity ............................................. 64
2.1.5 Appetite, eating patterns and adiposity ................................................ 65
2.1.6 The continuity and stabilitty of dietary intake and appetite from early to
mid-childhood ...................................................................................................... 65
2.2 Samples ........................................................................................................ 66
2.3 My contributions to the research included in this thesis ................................. 67

CHAPTER 3. SAMPLING AND METHODOLOGY ................................................ 68
3.1 Gemini – Health and Development in Twins .................................................. 68
3.2 Methods ........................................................................................................ 68
3.2.1 Study population and recruitment ............................................................ 68
3.2.1.1 Non-response analyses ................................................................ 69
3.2.2 Data collection ........................................................................................ 74
3.2.2.1 Socio-demographic information ..................................................... 76
3.2.2.1.1 Age ..................................................................................... 76
3.2.2.1.2 Socio-economic status ........................................................ 76
3.2.2.1.3 Ethnicity .............................................................................. 77
3.2.2.1.4 Representativeness of the Gemini sample .......................... 78
3.2.2.2 Appetitive traits ............................................................................. 82
3.2.2.3 Anthropometrics ............................................................................ 83
3.2.2.3.1 Adiposity aged two years..................................................... 84
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3.2.2.3.2 Growth up to five years of age ............................................. 85
3.2.2.4 Dietary intake (21 months of age) ................................................. 85
3.2.2.4.1 Portion guide ....................................................................... 86
3.2.2.4.2 Diet diary ............................................................................. 87
3.2.2.4.3 Coding of dietary data ......................................................... 90
3.2.2.4.4 Deriving dietary variables for analysis ................................. 91
3.2.2.4.4.1 Devising a coding system for classifying food and
drinks… ........................................................................................................... 91
3.2.2.4.4.2 Consumption patterns ................................................. 98
3.2.2.4.4.3 Meal composition ....................................................... 99
3.2.2.4.4.4 Energy and nutrient intakes ....................................... 100
3.2.2.4.5 Estimating misreporting of dietary intake ........................... 101
3.2.2.5 Dietary intake (seven years of age) ............................................. 104
3.2.2.5.1 Portion guide ..................................................................... 104
3.2.2.5.2 Diet diary ........................................................................... 105
3.2.2.5.3 Coding of dietary data ....................................................... 108
3.2.3 Statistical analyses ............................................................................... 108
3.2.3.1 Non-response analyses .............................................................. 108
3.2.3.2 Quantitative analyses .................................................................. 109
3.2.3.3 Qualitative analyses .................................................................... 109
3.2.3.4 Power.......................................................................................... 109
3.3 Discussion ................................................................................................... 110

CHAPTER 4. DIETARY INTAKES OF YOUNG CHILDREN IN THE UK ............. 111
4.1 Background ................................................................................................. 111
4.2 Study aim .................................................................................................... 112
4.3 Methods ...................................................................................................... 113
4.3.1 Study populations ............................................................................... 113
4.3.2 Measures ........................................................................................... 114
4.3.2.1 Dietary intake ............................................................................ 114
4.3.3 Statistical analyses ............................................................................. 115
4.3.3.1 Descriptive statistics .................................................................. 115
4.3.3.1.1 Energy and nutrient intakes .............................................. 115
4.3.3.1.2 Meal size and frequency ................................................... 116
4.3.3.1.3 Food and drink intakes ...................................................... 116
4.3.3.2 Comparisons between Gemini and the National Diet and Nutrition
Survey (NDNS) ................................................................................................. 116
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4.3.3.3 Comparisons with Dietary Reference Values ............................. 116
4.4 Results ........................................................................................................ 117
4.4.1 Sample characteristics ....................................................................... 117
4.4.2 Dietary intake in the Gemini sample ................................................... 119
4.4.2.1 Energy and nutrient intakes ...................................................... 119
4.4.2.2 Meal size and frequency ........................................................... 122
4.4.2.3 Food and drink intakes ............................................................. 123
4.4.3 Comparisons between Gemini and the National Diet and Nutrition
Survey (NDNS) ................................................................................................. 124
4.4.3.1 Energy and Nutrient intakes ...................................................... 124
4.4.3.2 Meal size and frequency ........................................................... 124
4.4.4 Comparisons with Dietary Reference Values ..................................... 124
4.5 Discussion ................................................................................................... 129
4.5.1 Summary of findings ........................................................................... 129
4.5.2 Implications ........................................................................................ 135
4.5.3 Strengths and limitations .................................................................... 137
4.5.4 Conclusions ........................................................................................ 138

CHAPTER 5. THE ROLE OF APPETITE IN FORMULA MILK AND FOOD INTAKE
IN EARLY LIFE .................................................................................................... 139
5.1 Background ................................................................................................. 139
5.2 Study aim .................................................................................................... 142
5.3 Methods ...................................................................................................... 142
5.3.1 Study population ................................................................................. 142
5.3.2 Measures ........................................................................................... 142
5.3.2.1 Appetite .................................................................................... 142
5.3.2.2 Dietary intake ............................................................................ 143
5.3.2.2.1 Formula consumption ...................................................... 143
5.3.2.2.2 Daily food and drink intake ............................................... 143
5.3.2.2.3 Daily energy intake .......................................................... 143
5.3.2.3 Anthropometrics and demographics......................................... 143
5.3.2.4 Qualitative interviews ............................................................... 143
5.3.3 Statistical analyses ............................................................................ 144
5.3.3.1 Identifying covariates ............................................................... 144
5.3.3.2 Quantitative analyses .............................................................. 144
5.3.3.2.1 Establishing relationships between extended formula milk
feeding and i) appetite, ii) food, milk and daily energy intake, and iii) adiposity . 144
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5.3.3.2.2 Establishing relationships between appetitive traits and total
milk consumption .............................................................................................. 145
5.3.3.3 Qualitative analyses ................................................................... 146
5.4 Results ........................................................................................................ 146
5.4.1 Quantitative study ............................................................................... 146
5.4.1.1 Sample characteristics .............................................................. 146
5.4.1.2 Descriptive statistics: formula consumption .............................. 148
5.4.1.3 The relationship betweeen extended formula milk feeding and i)
appetite, ii) food, milk and daily energy intake, and iii) adiposity ........................ 148
5.4.1.4 The relationship betweeen appetite and total milk
consumption ..................................................................................................... .152
5.4.2 Qualitative analyses ........................................................................... 153
5.4.2.1 Sample characteristics .............................................................. 153
5.4.2.2 Themes .................................................................................... 154
5.5 Discussion ................................................................................................... 157
5.5.1 Summary of findings ........................................................................... 157
5.5.2 Implications ........................................................................................ 159
5.5.3 Strengths and limitations .................................................................... 159
5.5.4 Conclusions ........................................................................................ 160

CHAPTER 6. APPETITIVE TRAITS AND CONSUMPTION PATTERNS IN EARLY
LIFE...................................................................................................................... 162
6.1 Background ................................................................................................. 162
6.2 Study aim .................................................................................................... 163
6.3 Methods ...................................................................................................... 164
6.3.1 Study population ................................................................................ 164
6.3.2 Measures .......................................................................................... 164
6.3.2.1 Appetite ................................................................................... 164
6.3.2.2 Dietary intake ........................................................................... 164
6.3.2.3 Anthropometrics and demographics......................................... 164
6.3.3 Statistical analyses ............................................................................ 165
6.3.3.1 Identifying covariates ............................................................... 165
6.3.3.2 Establishing associations between appetitive traits, consumption
patterns and daily energy intake ........................................................................ 165
6.4 Results ........................................................................................................ 166
6.4.1 Sample characteristics ...................................................................... 166
6.4.2 Associations between appetitive traits and consumption patterns ...... 169
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6.4.2.1 Appetite and eating patterns .................................................... 169
6.4.2.2 Appetite and drinking patterns ................................................. 169
6.4.3 Associations between appetitive traits and daily energy intake .......... 174
6.5 Discussion ................................................................................................... 175
6.5.1 Summary of findings .......................................................................... 175
6.5.2 Implications ........................................................................................ 177
6.5.3 Strengths and limitations .................................................................... 179
6.5.4 Conclusions ........................................................................................ 181

CHAPTER 7. CONSUMPTION PATTERNS IN EARLY LIFE AND
ADIPOSITY ........................................................................................................ ..182
7.1 Background ................................................................................................. 182
7.2 Study aim .................................................................................................... 184
7.3 Methods ...................................................................................................... 185
7.3.1 Study populations ............................................................................... 185
7.3.1.1 Gemini ....................................................................................... 185
7.3.1.2 Diet and Nutrition Survey for Infants and Young Children
(DNSIYC). ......................................................................................................... 186
7.3.2 Measures ........................................................................................... 187
7.3.2.1 Dietary intake ............................................................................ 187
7.3.2.1.1 Consumption patterns ...................................................... 187
7.3.2.1.2 Dietary composition ......................................................... 187
7.3.2.2 Anthropometrics and demographics ......................................... 187
7.3.2.2.1 Gemini ............................................................................. 187
7.3.2.2.2 DNSIYC ........................................................................... 188
7.3.2.3 Adjusting for misreporting of energy intake .............................. 189
7.3.3 Statistical analyses ............................................................................. 191
7.3.3.1 Meal size, meal frequency and weight gain ............................... 191
7.3.3.2 Characterising the relationships between meal size and meal
frequency .......................................................................................................... 191
7.3.3.3 Meal size, meal frequency and concurrent weight and weight
status ................................................................................................................ 192
7.3.3.4 Meal composition and weight status .......................................... 193
7.3.3.5 Replicating cross-sectional associations in a sample of singletons
from the DNSIYC .............................................................................................. 193
7.4 Results ........................................................................................................ 194
7.4.1 Sample characteristics ...................................................................... 194
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7.4.2 Meal size, meal frequency and weight gain ....................................... 198
7.4.3 Relationships between meal size and meal frequency ....................... 201
7.4.4 Meal size, meal frequency and concurrent weight and weight
status .............................................................................................................. ..203
7.4.4.1 Concurrent weight at two years of age ..................................... 203
7.4.4.2 Weight status at two and five years of age ............................... 205
7.4.5 Meal composition and weight status .................................................. 211
7.4.5.1 Weight status at two years of age ............................................ 211
7.4.5.2 Weight status at five years of age ............................................ 213
7.4.6 Replicating cross-sectional associations in a sample of singletons from
the DNSIYC ...................................................................................................... 215
7.4.6.1 Meal size, meal frequency and concurrent weight ...................... 215
7.4.6.2 Meal size, meal frequency and weight status .............................. 217
7.4.6.3 Meal composition and weight status ........................................... 223
7.5 Discussion ................................................................................................... 225
7.5.1 Summary of findings ........................................................................... 225
7.5.2 Implications ........................................................................................ 233
7.5.3 Strengths and limitations .................................................................... 235
7.5.4 Conclusions ........................................................................................ 239

CHAPTER 8. MEAL SIZE AS A MEDIATOR OF THE ASSOCIATION BETWEEN
SATIETY REPONSIVENESS AND ADIPOSITY................................................... 240
8.1 Background ................................................................................................. 240
8.2 Study aim .................................................................................................... 240
8.3 Methods ...................................................................................................... 240
8.3.1 Study population ................................................................................. 240
8.3.2 Measures ........................................................................................... 241
8.3.2.1 Satiety Responsiveness............................................................ 241
8.3.2.2 Meal size .................................................................................. 241
8.3.2.3 Anthropometrics and demographics ......................................... 241
8.3.3 Statistical analyses ........................................................................... 241
8.3.3.1 Residualised variables ............................................................... 241
8.3.3.2 Mediation analysis ..................................................................... 242
8.4 Results ........................................................................................................ 243
8.4.1 Sample characteristics ....................................................................... 243
8.4.2 Meal size as a mediator of the association between appetite and
adiposity ............................................................................................................ 246
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