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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Retrospectively registered

Titles & IDs
Public title
Susceptibility to Weight Gain: Studies of Appetite Regulation in Lean, Overweight & Obese Men & Women
Scientific title
Susceptibility to Weight Gain: Studies of Appetite Regulation
Secondary ID [1] 253565 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Appetite regulation 261122 0
Condition category
Condition code
Diet and Nutrition 259274 259274 0 0

Study type
Description of intervention(s) / exposure
The aims of the study are to identify eating & appetite behaviours which characterise people who may be susceptible to over-consumption, weight gain and obesity, by: (i) the use of eating behaviour questionnaires & (ii) investigating individuals responses to a range of dietary challenges which vary in energy, fat, carbohydrate & protein content.
There will be 5 visits to the Human Nutrition Unit appetite centre. One brief screening visit [Phase 1] (approx 40 min) plus 4 x 1 day study visits [Phase 2].

Visit 1 = Phase 1 characterization visit. This is a screening visit where volunteers will be consented and registered. At this visit subjects will complete a collection of screening questionnaires to complete the characterization phase of the study.
Visits 2-5 = Phase 2 intervention study visits. Once volunteers have completed the first phase of the study, they will come into the Human Nutrition Unit appetite centre fasted (=nothing to eat) on 4 additional separate days, arriving in the early morning (8am) and staying until the early afternoon (13:30pm).
The trial design will be a 4 treatment cross-over, single day intervention study comprising 100 healthy lean, overweight & obese male & female subjects (aged 18-60 years). Participants will be given either a high fat, low fat, high energy or low energy test breakfast followed by an ad libitum lunch meal 3.5 hours later. There will be a minimum washout period of 7 days in between treatments.
Each participant will complete all study arms of phase 2 in a randomized order according to a Latin square design.
The 4 interventions are:
A.High fat breakfast (2.5MJ; 50%en fat), followed by an ad libitum lunch meal.
B.Low fat breakfast (2.5MJ; 25%en fat), followed by an ad libitum lunch meal
C.High energy (2.5MJ; 37.5%en fat) breakfast, followed by an ad libitum lunch meal
D.Low energy (0.5.MJ; 37.5%enfat ) breakfast, followed by an ad libitum lunch meal
[MJ = mega joules; %en fat = the percent of the treatments energy contributed by fat]

The breakfast meals will comprise typical breakfast food items consumed in New Zealand including toast with butter & jam & scrambled eggs. All breakfast items provided must be consumed by participants.

The ad libitum lunch will comprise of a lamb casserole & rice. The lunch meal will provide items served in moderate excess and participants will be instructed to eat as much of all food items available until they feel comfortably full.
Intervention code [1] 257997 0
Comparator / control treatment
Patients act as their own control in this crossover study
Control group
Dose comparison

Primary outcome [1] 262091 0
The primary outcome is energy intake at the ad libitum lunch meal following the test breakfast meal. Lunch items will be weighed by research staff pre- and post-meal, and energy, fat, CHO and protein intake calculated using the dietary program Foodworks.
Timepoint [1] 262091 0
Lunch is served 3.5 hours (t=210 minutes) post the breakfast start time. Subjects have 30 minutes for lunch
Secondary outcome [1] 273138 0
Secondary Outcome 1: Visual Analogue Scale (VAS) scores for hunger and fullness.
Timepoint [1] 273138 0
Time points: t= 0, 15, 30, 45, 60, 120, 180, 210, 240 270 and 300 mins. These time points are set assuming t=0 is the time the breakfast meal is administered.
Secondary outcome [2] 273139 0
Secondary Outcome 2: Visual Analogue Scale (VAS) scores for satisfaction and thoughts of food.
Timepoint [2] 273139 0
Time points: t= 0, 15, 30, 45, 60, 120, 180, 210, 240 270 and 300 mins. These time points are set assuming t=0 is the time the breakfast meal is administered.

Key inclusion criteria
1. men and women, aged 18-60y
2. lean, overweight or obese
3. all ethnicities
4. desire to participate in clinical trial
Minimum age
18 Years
Maximum age
60 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
1. Vegetarian/ vegan
2. Smoking (current or previous 6 months)
3. Appetite suppressant medications e.g. sibutramine
4. Known allergy or hypersensitivity to any trial food ingredients
5. unwilling or unable to comply with protocol/ participation in another clinical trial

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
This is a randomised, cross-over trial. Randomisation is carried out using a Latin square design which is stratified to match the high fat & low fat breakfasts (treatments A & B) and the high energy & low energy breakfasts (treatments C & D) together. The order in which eligible participants are enrolled will determine the order in which they will complete the treatment arms. Allocation is not concealed.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
The randomisation will be stratified to ensure that treatments (A)/(B) & (C)/(D) are completed as 2 x 2 pairs in the latin square design to maximise outcome considering potential drop out
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not applicable
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment outside Australia
Country [1] 3170 0
New Zealand
State/province [1] 3170 0

Funding & Sponsors
Funding source category [1] 258459 0
Name [1] 258459 0
The University of Auckland
Address [1] 258459 0
Human Nutrition Unit, The University of Auckland, 18 Carrick Place, Mt Eden 1024
Country [1] 258459 0
New Zealand
Primary sponsor type
The University of Auckland
Human Nutrition Unit, the University of Auckland, 18 Carrick Place, Mt Eden 1024
New Zealand
Secondary sponsor category [1] 257601 0
Name [1] 257601 0
Address [1] 257601 0
Country [1] 257601 0
Other collaborator category [1] 251809 0
Name [1] 251809 0
Queensland University of Technology
Address [1] 251809 0
Institute of Health and Biomedical Innovation (IHBI)
Queensland University of Technology (QUT), 60 Musk Avenue, Kelvin Grove Urban Village, Kelvin Grove, Queensland, 4059 Australia
Country [1] 251809 0

Ethics approval
Ethics application status
Ethics committee name [1] 260437 0
Northern X Regional Ethics Comittee
Ethics committee address [1] 260437 0
3rd floor, Unisys Building 650 Great South Rd Penrose 1061. Private Bag 92-522, Wellesley St Auckland
Ethics committee country [1] 260437 0
New Zealand
Date submitted for ethics approval [1] 260437 0
Approval date [1] 260437 0
Ethics approval number [1] 260437 0

Brief summary
Appetite regulation, which encompasses the physiological control of sensations of hunger and fullness as well as the regulation of food intake, is key to the prevention and treatment of obesity (Blundell et al, 1993; Uay & Diaz 2005; Abete et al. 2007)

It is clear that groups of individuals within the population have greater susceptibility to obesity than their lean counterparts, despite comparable environmental pressure encouraging overconsumption and sedentary behaviour, and that these individuals preferentially gain body weight (adiposity) and hence are overweight and/or obese (Blundell & Cooling 1999; Blundell et al 2002, 2005).

It is likely that appetite-related behaviours which characterise an increased susceptibility to obesity can be identified through a combination of:
a) administration of questionnaires investigating eating behaviour
[characterization] and
b) identification of responses to acute dietary interventions designed to assess feelings of hunger, fullness & associated appetitive sensations and measure eating behaviour (i.e. food intake) [intervention]
Trial website
Not applicable
Trial related presentations / publications
Public notes

Principal investigator
Name 32187 0
Prof Sally Poppitt
Address 32187 0
18 Carrirck Place
Mt Eden
Auckland 1024
Country 32187 0
New Zealand
Phone 32187 0
Fax 32187 0
Email 32187 0
Contact person for public queries
Name 15434 0
Miss Katy Wiessing
Address 15434 0
Human Nutrition Unit, the University of Auckland, 18 Carrick Place, Mt Eden 1024
Country 15434 0
New Zealand
Phone 15434 0
+64 9 630 3744
Fax 15434 0
+64 9 630 5764
Email 15434 0
Contact person for scientific queries
Name 6362 0
Prof Sally Poppitt
Address 6362 0
Human Nutrition Unit, the University of Auckland, 18 Carrick Place, Mt Eden 1024
Country 6362 0
New Zealand
Phone 6362 0
+64 9 630 5160
Fax 6362 0
+64 9 630 5764
Email 6362 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary