Zinc Absorption From Zinc Biofortified Rice

Summary

a. To measure the amount of zinc absorbed from ZnBfR compared with the amount absorbed from CR and from CR fortified with added zinc, using the triple stable isotope tracer ratio technique in young children.

Methods:

Investigators will measure the amount of zinc absorbed from ZnBfR compared to that absorbed from a conventional Bangladeshi rice (Diet-CR) (control). They will also compare the zinc absorption from ZnBfR with that from zinc-fortified conventional rice (Diet-CR+Z). The study will be a cross-over, randomized, controlled clinical study. Forty-four children aged 36-59 mo of either sex will be recruited from the same community as mentioned before, and participants will be individually randomized, in equal numbers, to one of the two comparison groups, A and B. During an initial one-day acclimatization period, the participants will receive the conventional rice-based diet three times a day, to confirm that participants will accept the study diets and adhere to the study procedures. On study days 2 and 4, in comparison group A, participants will receive either the Diet-ZBfR or Diet-CR based on the random assignments, and participants will receive Diet-CR or Diet ZBfR, respectively, on days 3 and 5 (i.e., the diet not received on days 2 and 4), Likewise, in comparison group B, the participants will receive either Diet-ZBfR or Diet-CR+Z on days 2 and 4 based on the random assignments, and participants will receive Diet-CR+Z or the Diet-ZBfR, respectively, on days 3 and 5 (i.e., the diet not received on days 2 and 4). Investigators will use zinc stable isotope tracer techniques to measure the fractional absorption of zinc, in which tracer:tracee ratios will be measured in spot urine samples following administration of an intravenously administered tracer (68Zn) and one of two oral tracers (70Zn, 67Zn) provided with test meals over a four-day period.

Outcome measures/variables:

Intake of total dietary zinc (TDZ) and phytate for each subject will be calculated during the clinical study. Fractional absorption of zinc (FAZ) will be determined from the isotopic ratios obtained in urine samples using the following equation, which shows, as an example, the calculation that will be used for zinc absorption from the diet traced with 67Zn:

FAZ = 67Zn tracer:tracee ratio / 68Zn tracer:tracee ratio \* (68Zn dose given IV / 67Zn dose given orally)

Total absorbed zinc (TAZ) for each child will be calculated as follows:

TAZ (mg/d) = TDZ (mg/d) \* FAZ

Conditions

• Malnourished Children

Interventions

OTHER

Diet-ZnBfR

zinc biofortified rice-based diet

OTHER

Diet- CR

conventional rice-based diet

OTHER

Diet-ZnBfR

zinc biofortified rice-based diet

OTHER

CR + Zn

conventional rice-based diet plus zinc fortificant (Diet-CR+Z).

Sponsors & Collaborators

• HarvestPlus

  collaborator OTHER

• International Atomic Energy Agency

  collaborator OTHER_GOV

• International Centre for Diarrhoeal Disease Research, Bangladesh

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

36 Months

Max Age

59 Months

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2009-10-31

Primary Completion

2011-01-31

Completion

2011-01-31

Countries

• Bangladesh

Study Locations