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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
Targeting the ileal brake – effects of carbohydrate (CHO) on hunger, satiety and energy intake
Scientific title
Targeting the ileal brake – effects of carbohydrate (CHO) on hunger, satiety and energy intake: A Tube Feeding Study in healthy male participants
Secondary ID [1] 280307 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Appetite regulation 286266 0
Condition category
Condition code
Oral and Gastrointestinal 286487 286487 0 0
Normal oral and gastrointestinal development and function

Study type
Description of intervention(s) / exposure
This is a gastrointestinal infusion study where a CHO load or saline control will be infused directly into the distal ileum and the proximal duodenum using an extended naso-gastric (NG) feeding tube (catheter). Introduction of an NG catheter is a commonly used clinical procedure in enterally fed patients.
The objective of this study is to determine whether direct infusion of dietary CHO into the distal small intestine (terminal ileum) alters appetite-related sensations and food intake in a group of lean healthy men.
The study aims to determine the effect of CHO infused into the ileum using a naso-ileal (NI) tube on:
(i) subjective VAS-rated feelings of hunger, fullness and associated measures of satiety
(ii) energy intake at a subsequent lunch and dinner meal
(iii) gut peptides associated with satiety including cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1) and peptide YY (PYY)
The primary hypotheses are:

1. Infusion of a CHO load into the ileum will increase satiety and decrease subsequent food intake when compared with a duodenal infusion

2. Infusion of a CHO load into the ileum will increase circulating levels of the appetite-related gut peptides CCK, GLP-1 and PYY.

This is a 5 day residential study.
Four treatments comprising:
1. Saline control – infused into the duodenum
2. Glucose - infused into the duodenum
3. Saline control - infused into the ileum
4. Glucose - infused into the ileum

The CHO dose will be a 15g bolus of glucose

The infusions wil be administered over a duration of 1.5 hours. Participants will receive all 4 infusion treatments in a random order
Intervention code [1] 284657 0
Treatment: Other
Comparator / control treatment
Control group

Primary outcome [1] 286930 0
Visual Analogue Scale (VAS) scores for hunger and fullness.
Timepoint [1] 286930 0
Subjective ratings of satiety and nausea measured using visual analogue scales (VAS) at -120, -105, -90, -60, -30 & 0 (immediately before the test preload), 15, 30, 45, 60, 90, 120 (ad lib lunch), 150, 180, 240, 300, 360, 420 and 480 (ad lib dinner) and 510 minutes post preload.
t = 0 is the time that the infusion (treatment) begins
Secondary outcome [1] 297011 0
Energy Intake at ad libitum lunch meal. Energy, fat, carbohydrate (CHO) and protein intake will be calculated using the dietary program Foodworks Copyright (c) 1998-2007 Xyris Software.
Timepoint [1] 297011 0
Immediately post the ad libitum lunch, snack & dinner meals (t=150, t=255 and t=510)

Key inclusion criteria
Age 18-60 years
Lean, as defined by BMI <25kg/m2
Healthy, as ascertained by self-report and blood test
Minimum age
18 Years
Maximum age
60 Years
Can healthy volunteers participate?
Key exclusion criteria
Any medical conditions or medications known to affect appetite -related parameters, including depression
Low iron status, hence unsuitable for cannulation studies
Participation in an active diet program and/or loss/gain of >10% body weight within the last 6 months
Smoker or ex-smoker who quit within the last 6 months
Hypersensitivities or allergies to any foods or ingredients included in the study
Dislike and/or unwilling to consume items listed as study foods
Unwilling/unable to comply with study protocol
Participating in another clinical intervention 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, whereby the order at which participants agree to commence the study determines the order at which they receive the treatments Participants are randomized to receive all 4 treatments. the person who determined if a subject was eligible for inclusion in the trial was unaware, when this decision was made, to which group the subject would be allocated.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
A Latin square will be used to randomise the subjects to each of the 4 intervention arms. Each participant is randomized to complete all 4 intervention arms.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
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] 4252 0
New Zealand
State/province [1] 4252 0

Funding & Sponsors
Funding source category [1] 285076 0
Government body
Name [1] 285076 0
Foundation for Science and Research (FRST)/Ministry of Science Innovation
Address [1] 285076 0
Wellington office
Level 3, 33 Bowen Street.

PO Box 5762
Wellington 6145
Country [1] 285076 0
New Zealand
Primary sponsor type
Government body
Foundation for Science and Research (FRST)Ministry of Science Innovation
Wellington office
Level 3, 33 Bowen Street.

PO Box 5762
Wellington 6145
New Zealand
Secondary sponsor category [1] 283939 0
Name [1] 283939 0
Address [1] 283939 0
Country [1] 283939 0
Other collaborator category [1] 260719 0
Name [1] 260719 0
The University of Auckland
Address [1] 260719 0
Human Nutrition Unit
University of Auckland
18 Carrick Place
Mt Eden
Auckland 1024
Country [1] 260719 0
New Zealand
Other collaborator category [2] 260720 0
Commercial sector/Industry
Name [2] 260720 0
Plant & Food Research Ltd
Address [2] 260720 0
120 Mt Albert Road
Sandringham 1142
Country [2] 260720 0
New Zealand

Ethics approval
Ethics application status
Ethics committee name [1] 287088 0
Northern Y Regional Ethics Committee
Ethics committee address [1] 287088 0
C/o Ministry of Health
PO Box 1031
Hamilton 3240
Ethics committee country [1] 287088 0
New Zealand
Date submitted for ethics approval [1] 287088 0
Approval date [1] 287088 0
Ethics approval number [1] 287088 0

Brief summary
The GI tract is the source of a large number of signals and mechanisms purported to be involved in the control of satiety, and which are generated by various types of mechanical or chemical stimuli. Mechanical stimulation is provided by distension of the luminal wall as foods transit the length of the gut, whilst chemical stimulation is provided by the nutrients entering the small and possibly also the large intestine. These stimuli then result in release of GI peptides and/or the activation of neural signals which may alter appetite-related sensations and eating behaviour.

Secretion of GI peptides, when combined with neural signals from the stomach and small intestine generated by GI distension during and after meal ingestion, may lead to meal termination (=satiation) or may influence hunger and fullness between meals (=satiety).

The ileum, or distal small intestine, has become the focus of recent studies which have hypothesised that stimulation of the ileum as a consequence of nutrient arrival may generate a range of satiety signals which enhance fullness, suppress hunger and decrease food intake. The mechanism by which this may occur has been termed the ‘Ileal Brake’.

There are a range of feeding studies (Burns et al., 2000; Burns et al., 2001; Burns et al., 2002; Diepvens et al., 2007; Chan et al., 2010; Smit et al., 2010) which have shown appetite suppression in which the authours have attributed the effect to the delivery of nutrients to the ileum which in turn has stimulated the ileal brake. Studies conducted to date have focused on the delivery of dietary lipids, in particular lipid emulsions (Read et al., 1984a; Van Citters & Lin, 1999). Long-chain fatty acids are potent triggers of the ileal brake & several studies have demonstrated that the ileal brake may be activated by small amounts of fat or free fatty acids. The ileal brake has also been identified as a potentially important mechanism following delivery of CHO's.
Trial website
Trial related presentations / publications
The results of this trial have not been published, yet.
Public notes

Principal investigator
Name 34050 0
Prof Sally Poppitt
Address 34050 0
Human Nutrition Unit
18 Carrick Place, Mt Eden, Auckland, 1024
New Zealand
Country 34050 0
New Zealand
Phone 34050 0
Fax 34050 0
Email 34050 0
Contact person for public queries
Name 17297 0
Prof Sally Poppitt
Address 17297 0
Human Nutrition Unit
University of Auckland
18 Carrick Place
My Eden
Auckland 1024
Country 17297 0
New Zealand
Phone 17297 0
+64 9 630 5160
Fax 17297 0
+64 9 630 5764
Email 17297 0
Contact person for scientific queries
Name 8225 0
Prof Sally Poppitt
Address 8225 0
Human Nutrition Unit
University of Auckland
18 Carrick Place
My Eden
Auckland 1024
Country 8225 0
New Zealand
Phone 8225 0
+64 9 630 5160
Fax 8225 0
+64 9 630 5764
Email 8225 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