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Trial registered on ANZCTR

Trial ID
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
The effect of kiwifruit on digestion in healthy adult males.
Scientific title
A randomised controlled cross over study to examine the influence of Actinidin from green kiwifruit on digestion in healthy adult males.
Secondary ID [1] 285313 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Gastrointestinal comfort 293025 0
Condition category
Condition code
Oral and Gastrointestinal 293296 293296 0 0
Normal oral and gastrointestinal development and function

Study type
Description of intervention(s) / exposure
A randomised controlled crossover study of 10 healthy males.
Test meals are: 400g steak with two Gold Kiwifruit & 250 ml water X 2 : 400g steak with two Green kiwifruit & 250 ml water X1
Visits: Participants will arrive having fasted overnight following the consumption of a standard meal. On arrival they will complete VAS scales rating feelings of hunger, satisfaction, fullness and comfort. They will be given the test food and asked to eat it in full at their own pace but within15 minutes. They will immediately be asked to swallow the SmartPIll, attach the transponder and complete further VAS scales which will be repeated each hour for a total of 5 hours. Participants will be given an ad libitum lunch after 5 hours to assess energy intake. Items will be given in moderate excess and participants will be asked to stop eating when comfortably full but will remain for a time period of 30 minutes. Meals will be weighed before and after consumption to assess energy intake. After 5 days, the participants will visit to return the transponder for downloading of the data. After least 7 days, participants will return to consume the next randomised test meal until all three meals have been consumed
Intervention code [1] 290223 0
Comparator / control treatment
The addition of two Gold HORT 16A kiwifruit which have negligible Actinidin levels to a high protein meal consisting of 400g stir fried steak
Control group

Primary outcome [1] 293130 0
The primary outcome will be the rate of gastric emptying times as assessed by SmartPill technology.
Timepoint [1] 293130 0
5 days
Primary outcome [2] 293214 0
The primary outcome will be the rate of small bowel transit times as assessed by SmartPill technology.
Timepoint [2] 293214 0
5 days
Secondary outcome [1] 310418 0
Subjective feelings of hunger and fullness as assessed by visual analogue scales
Timepoint [1] 310418 0
0,15 minutes, 1,2,3,4,5 hours
Secondary outcome [2] 310602 0
Subjective feelings of gastric comfort as assessed by questions with set ratings.
Timepoint [2] 310602 0
0,15 minutes, 1,2,3,4,5 hours
Secondary outcome [3] 310772 0
Energy intake of ad libitum lunch which will be assessed by offering the participants a restricted buffet-style
meal with predominantly cold and one hot meal choice,
along with a selection of beverages. In an attempt to avoid
over-consumption the variation of meal items will be limited. Participants will be advised that they can eat as
much or as little as they chose and that they are to
remain in the room for a period of 45 minutes. The remaining food items will be weighted and the quantity of food consumed estimated.
Timepoint [3] 310772 0
5 hours

Key inclusion criteria
10 generally healthy males. BMI 19 to 30 kg/m2
Minimum age
18 Years
Maximum age
50 Years
Can healthy volunteers participate?
Key exclusion criteria
Major Illness - cardiovascular disease, diabetes, cancer, renal failure, previous gastrointestinal surgery (not including appendectomy), neurological conditions (stroke, multiple sclerosis, spinal cord injury); gastrointestinal disorders such as Crohn's disease, IBS, diverticulitis; major food allergies; allergies to kiwifruit; extreme dietary habits

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Subjects will be enrolled by investigators folllowing a face to face interview and given a unique identifying number for labelling all further trial data. This ID number will be provided to an independent biostatisician who will randomise the participants to the treatment schedule
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
simple randomisation by using a randomization table created by a computer software (i.e. computerised sequence generation
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis
A sample of ten participants in a cross-over design was chosen following Timm and others (2011), who found significant differences in colonic and whole gut transit times between high and low fibre meals using similar measurement techniques and ten participants.
Initial calculations have been made on the available data.VAS data will be analysed using a repeated measures Linear
Mixed Model ANOVA. MANOVA will be
also used to generate a full model for VAS incorporating
all dependent variables. Energy and macronutrient intake
data from the ad lib lunch meal will be analysed using univariate ANOVA Univariate ANOVA. The trial will be analysed on the basis of intention to treat (ITT). Statistical significance will be based on 95% limits (P < 0.05).

Timm, Derek. The use of a wireless motility device (SmartPill 'Registered Trademark') for the measurement of gastrointestinal transit time after a dietary fibre intervention. British Journal of Nutrition; 2011: 105;1337-1342

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] 6345 0
New Zealand
State/province [1] 6345 0

Funding & Sponsors
Funding source category [1] 289931 0
Commercial sector/Industry
Name [1] 289931 0
Zespri International Ltd
Address [1] 289931 0
40 Maunganui Road
Mt Maunganui
New Zealand 3116
Country [1] 289931 0
New Zealand
Primary sponsor type
Government body
The New Zealand Institute for Plant & Food Research Limited
Gerald Street, Lincoln, Christchurch 8140
New Zealand
Secondary sponsor category [1] 288623 0
Name [1] 288623 0
Address [1] 288623 0
Country [1] 288623 0

Ethics approval
Ethics application status
Ethics committee name [1] 291648 0
Health and Disability Council
Ethics committee address [1] 291648 0
Ministry of Health
No 1 The Terrace
PO Box 5013
Wellington 6145
Ethics committee country [1] 291648 0
New Zealand
Date submitted for ethics approval [1] 291648 0
Approval date [1] 291648 0
Ethics approval number [1] 291648 0

Brief summary
The consumption of green kiwifruit, Actinidia deliciosa cv. ‘Hayward”, has been thought to assist in the digestion of food for many years and this has largely been attributed to the presence of the proteolytic enzyme actinidin. Actinidin has been shown to enhance the digestion of protein during the digestive process reducing feelings of over fullness and gastric discomfort following a high protein meal. This study aims to examine the effect of consuming green kiwifruit (containing high levels of the enzyme Actinidin) alongside a high protein meal of 400g steak and measuring the transit rate of the food through the Gastrointestinal tract using SmartPill technology. SmartPill is a wireless single use, ingestible capsule that uses sensor technology to measure pH, pressure and temperature throughout the entire gastrointestinal tract (GIT) over a five day period . They will also be asked to rate feelings of fullness and gastric comfort using visual analogue scales over a 5 hour period. Following an interval of at least seven days, the participants will then cross over to repeat the study and consume the same meat meal with Gold kiwifruit (contains low levels of Actinidin) as a comparison.
Trial website
Trial related presentations / publications
Commercial report completed and accepted by Zespri International Ltd. 01/02/2015
Public notes

Principal investigator
Name 51342 0
A/Prof Richard Gearry
Address 51342 0
Gastroenterology & Endoscopy
Christchurch School of Medicine
University of Otago
PO Box 3932
Christchurch 8140
Country 51342 0
New Zealand
Phone 51342 0
64 3 3786236
Fax 51342 0
64 3 3786299
Email 51342 0
Contact person for public queries
Name 51343 0
Ms Sarah Eady
Address 51343 0
Plant & Food Research
PO Box 4704
Christchurch 8140
Country 51343 0
New Zealand
Phone 51343 0
64 3 3259671
Fax 51343 0
64 3 3252074
Email 51343 0
Contact person for scientific queries
Name 51344 0
Ms Sarah Eady
Address 51344 0
Plant & Food Research
PO Box 4704
Christchurch 8140
Country 51344 0
New Zealand
Phone 51344 0
64 3 3259671
Fax 51344 0
64 3 3252074
Email 51344 0