ANZCTR - Registration

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Trial registered on ANZCTR

Registration number

ACTRN12611000162910

Ethics application status

Approved

Date submitted

9/02/2011

Date registered

10/02/2011

Date last updated

27/10/2016

Type of registration

Prospectively registered

Titles & IDs

Public title

Vitamin C uptake from kiwifruit compared with a vitamin C supplement

Scientific title

Vitamin C bioavailability from kiwifruit compared with a vitamin C supplement - a randomised parallel study in men

Secondary ID [1]

Nil

Universal Trial Number (UTN)

Nil

Trial acronym

Linked study record

Health condition

Health condition(s) or problem(s) studied:

Vitamin C status

Condition category

Condition code

Public Health

Health promotion/education

Intervention/exposure

Study type

Interventional

Description of intervention(s) / exposure

Arm 1 - baseline period (4 weeks) to monitor dietary intake of vitamin C; intervention period (6 weeks) - gold kiwifruit (half/day); washout period (4 weeks) to monitor return of plasma vitamin C to baseline levels. Arm 2 - baseline period (4 weeks) to monitor dietary intake of vitamin C; intervention period (6 weeks) - chewable vitamin C tablet (45mg/day); washout period (4 weeks) to monitor return of plasma vitamin C to baseline levels. Arm 3 - baseline period (4 weeks) to monitor dietary intake of vitamin C; intervention period (6 weeks) - gold kiwifruit (two/day); washout period (4 weeks) to monitor return of plasma vitamin C to baseline levels.

Intervention code [1]

Lifestyle

Intervention code [2]

Treatment: Other

Comparator / control treatment

Arm 2 - vitamin C supplement

Control group

Active

Outcomes

Primary outcome [1]

Measurement of vitamin C status of blood plasma by HPLC

Timepoint [1]

Weekly for 14-16 weeks

Secondary outcome [1]

Measurement of vitamin C status of white blood cells by HPLC

Timepoint [1]

Before intervention and after intervention (6-8 weeks)

Secondary outcome [2]

Measurement of vitamin C status of urine by HPLC

Timepoint [2]

Before intervention and after intervention (6-8 weeks)

Secondary outcome [3]

Measurement of vitamin C status of seminal fluid by HPLC

Timepoint [3]

Before intervention and after intervention (6-8 weeks)

Secondary outcome [4]

Measurement of vitamin C status of muscle biopsies by HPLC

Timepoint [4]

Before intervention and after intervention (6-8 weeks)

Secondary outcome [5]

Assessment of Profile of Mood States questionnaire

Timepoint [5]

Before intervention and after intervention (6-8 weeks)

Eligibility

Key inclusion criteria

Male aged 18-30 years
Non-smoker
Low/below average plasma vitamin C levels (<40 uM)
Residing in Christchurch for the duration of the study

Minimum age

18 Years

Maximum age

30 Years

Sex

Males

Can healthy volunteers participate?

Yes

Key exclusion criteria

Recent smoker (within previous year)
Allergy/intolerance to kiwifruit
Taking vitamin C containing supplements (within past three months)
Excessive alcohol consumption (>21 standard drinks/week)
High fruit and vegetable consumption (>5 servings/day)
Diabetes mellitus
Bleeding disorders
Obese (>35 kg/m2)
Fear of needles

Study design

Purpose of the study

Prevention

Allocation to intervention

Randomised controlled trial

Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)

Participants will be enrolled following screening for low vitamin C status
Allocation to intervention will be by sealed opaque envelopes

Methods used to generate the sequence in which subjects will be randomised (sequence generation)

Participants will be randomised via coin toss

Masking / blinding

Open (masking not used)

Who is / are masked / blinded?

Intervention assignment

Parallel

Other design features

Phase

Not Applicable

Type of endpoint/s

Bio-availability

Statistical methods / analysis

Recruitment

Recruitment status

Completed

Date of first participant enrolment

Anticipated

13/06/2011

Actual

15/06/2011

Date of last participant enrolment

Anticipated

Actual

26/07/2011

Date of last data collection

Anticipated

Actual

13/12/2011

Sample size

Target

50

Accrual to date

Final

54

Recruitment outside Australia

Country [1]

New Zealand

State/province [1]

Canterbury

Funding & Sponsors

Funding source category [1]

Commercial sector/Industry

Name [1]

Zespri International Ltd

Address [1]

400 Maunganui Road
Mount Maunganui 3116

Country [1]

New Zealand

Primary sponsor type

Individual

Name

Margreet Vissers

Address

University of Otago, Chirsthurch
2 Riccarton Ave
Christchurch 8140

Country

New Zealand

Secondary sponsor category [1]

Individual

Name [1]

Anitra Carr

Address [1]

University of Otago, Chirsthurch
2 Riccarton Ave
Christchurch 8140

Country [1]

New Zealand

Ethics approval

Ethics application status

Approved

Ethics committee name [1]

Upper South Regional Ethics Committee

Ethics committee address [1]

250 Oxford Terrace 
Christchurch 8011

Ethics committee country [1]

New Zealand

Date submitted for ethics approval [1]

07/02/2011

Approval date [1]

Ethics approval number [1]

Summary

Brief summary

Vitamin C is an essential nutrient which is not produced in humans and consequently must be obtained through dietary sources.  Kiwifruit is an outstanding commonly available source of vitamin C, one serving providing about twice the recommended daily intake of the vitamin.  We are proposing to investigate the uptake of vitamin C from kiwifruit compared with a vitamin C supplement using a randomised parallel groups study design.  We will screen individuals for low vitamin C status and each participant will be randomised to receive either kiwifruit or a vitamin C supplement.  The vitamin C status of the participant’s blood plasma will be measured regularly as an indication of dietary intake of the vitamin.  Food and beverage records will also be filled out periodically to monitor the participant’s dietary intake of the vitamin.  The vitamin C levels of urine, semen, white blood cells and muscle tissue will be measured at the beginning and end of the supplementation period to determine cellular accumulation and excretion of the vitamin.  Overall, the proposed study will provide valuable information as to how the body accumulates and stores vitamin C, and whether or not a food source of the vitamin is preferred over a dietary supplement.

Trial website

Trial related presentations / publications

Carr AC, Bozonet SM, Pullar JM, Simcock JW, Vissers MC. A randomized steady-state bioavailability study of synthetic versus natural (kiwifruit-derived) vitamin C. Nutrients. 2013 Sep 17;5(9):3684-95. 


Carr, A.C., Bozonet S.M., Pullar, J.M., Vissers, M.C.M. (2013). Mood improvement in young adult males following supplementation with gold kiwifruit, a high vitamin C food. J Nutr Sci. 2 (e24), 1-8. doi:10.1017/jns.2013.12.


Carr, A.C., Bozonet S.M., Pullar, J.M., Simcock, J.W., Vissers, M.C.M. (2013). Human skeletal muscle ascorbate is highly responsive to changes in vitamin C intake and plasma concentrations. Am J Clin Nutr. 97 (4), 800-807.

Public notes

Contacts

Principal investigator

Name

Prof Margreet Vissers

Address

University of Otago, Christchurch 2 Riccarton Ave Christchurch 8140

Country

New Zealand

Phone

64 3 364 1524

Fax

Email

margreet.vissers@otago.ac.nz

Contact person for public queries

Name

Anitra Carr

Address

University of Otago, Christchurch
2 Riccarton Ave
Christchurch 8140

Country

New Zealand

Phone

64 3 378 6498

Fax

Email

anitra.carr@otago.ac.nz

Contact person for scientific queries

Name

Margreet Vissers

Address

University of Otago, Christchurch
2 Riccarton Ave
Christchurch 8140

Country

New Zealand

Phone

64 3 364 1524

Fax

Email

margreet.vissers@otago.ac.nz

No information has been provided regarding IPD availability

What supporting documents are/will be available?

No Supporting Document Provided

Results publications and other study-related documents

Documents added manually

No documents have been uploaded by study researchers.

Documents added automatically

Source	Title	Year of Publication	DOI
Dimensions AI	Mood improvement in young adult males following supplementation with gold kiwifruit, a high-vitamin C food	2013	https://doi.org/10.1017/jns.2013.12
Embase	Marginal ascorbate status (Hypovitaminosis C) results in an attenuated response to vitamin C supplementation.	2016	https://dx.doi.org/10.3390/nu8060341

N.B. These documents automatically identified may not have been verified by the study sponsor.