Nutrient Physiology, Metabolism,
and Nutrient-Nutrient Interactions
Demonstrating Zinc and Iron Bioavailability from Intrinsically Labeled
Microencapsulated Ferrous Fumarate and Zinc Gluconate Sprinkles
in Young Children1
Stanley H. Zlotkin,* **y yy2,3Claudia Schauer,yySeth Owusu Agyei,zzJulian Wolfson,yy
Melody C. Tondeur,y yyKwaku P. Asante,zzSamuel Newton,zzRobert E. Serfass,#
and Waseem Sharieffzyy
*Departments of Paediatrics,yNutritional Sciences, andzHealth Policy, Management, and Evaluation and
**Centre for International Health, University of Toronto, Toronto, Canada;yyDivision of Gastroenterology and
Nutrition, Programs in Metabolism and Integrative Biology, Research Institute, The Hospital for Sick Children,
M5G 1X8 Toronto, Canada;zzKintampo Health Research Centre Health Research Unit, Ghana Health
Service, Kintampo, Brong Ahafo, Ghana; and#Department of Preventive Medicine and Community Health,
University of Texas Medical Branch, Galveston, TX 77555
including Sprinkles, a home-fortification strategy to control anemia. The objectives of this randomized controlled trial
were as follows: 1) to compare the absorption of zinc at 2 doses given as Sprinkles; and 2) to examine the effect of
zinc and ascorbic acid (AA) on iron absorption from Sprinkles. Seventy-five children aged 12–24 mo were randomly
assigned to the following groups: 1) 5 mg of labeled zinc (67Zn) with 50 mg AA (LoZn group); b) 10 mg of labeled zinc
(67Zn) with 50 mg AA (HiZn group); or 3) 5 mg zinc with no AA (control). All groups contained 30 mg of labeled iron
(57Fe). Intravenous infusions labeled with70Zn (LoZn and HiZn groups) and58Fe (control) were administered. Blood
was drawn at baseline, 48 h and 14 d later. The percentage of zinc absorbed did not differ between LoZn (geometric
mean ¼ 6.4%; min-max: 1.7–14.6) and HiZn (geometric mean ¼ 7.5%; min-max: 3.3–18.0) groups. However, total
zinc absorbed was significantly different between the LoZn (geometric mean ¼ 0.31 mg; min-max: 0.08–0.73) and
HiZn (geometric mean ¼ 0.82 mg; min-max: 0.33–1.82) groups (P ¼ 0.0004). Geometric mean percentage iron
absorption values did not differ between the LoZn (5.9%; min-max: 0.8–21) and HiZn (4.4%; min-max: 0.6–12.3)
groups and between the LoZn and control groups (5.0%; min-max: 1.4–24). We conclude that zinc in the form of
Sprinkles has a low bioavailability, yet provides adequate amounts of absorbed zinc in young children, and that there
is no effect of zinc or AA on iron absorption from the given formulations of Sprinkles.
Nutrient-nutrient interactions are an important consideration for any multiple-micronutrient formulation,
J. Nutr. 136: 920–925, 2006.
KEY WORDS: ? home-fortification ? stable isotopes ? zinc absorption ? iron absorption ? Sprinkles
In recent years, it has become evident that young children
6–24 mo of age comprise a high-risk group for concurrent iron
and zinc deficiencies in most developing countries (1). Home-
fortification is a new approach to improve the micronutrient
content of complementary foods. Single-dose sachets (called
Sprinkles) containing micronutrients in powdered form (in-
cluding microencapsulated iron, zinc, vitamin A, folic acid, and
ascorbic acid) are easily added to foods prepared in the
household just before serving (2). Using dual stable isotopes
and intrinsically labeled microencapsulated ferrous fumarate,
we recently demonstrated that iron absorption is twice as high
in children with iron deficiency anemia than in nonanemic
children (3). Notwithstanding these positive results, an im-
portant unanswered question is the effect of the concurrent
ingestion of both iron and zinc (in Sprinkles) and their
interaction. Due to the potential negative effect on micro-
nutrient status from minerals that are competing for absorption,
ensuring that both iron and zinc are bioavailable merits
particular attention (4). Also of interest is the effect of ascorbic
acid on the absorption of iron from Sprinkles. Ascorbic acid was
shown to have a dose-dependent enhancing effect on nonheme
iron absorption (5). Yet, reports in the literature suggest that
ascorbic acid may not enhance the absorption of iron from
foods fortified with ferrous fumarate (6,7).
1Supported by a grant from the Canadian Institutes of Health Research
(CIHR) and the H.J. Heinz Company Foundation. Particle Dynamics Incorporated
and Dr. Paul Lohmann GmbH KG generously provided technical support.
2S. Zlotkin owns the intellectual property rights to micronutrient Sprinklese. All
profits net of expenses from the licensing of Sprinkles are donated to the Hospital
for Sick Children Foundation. There are no other ‘‘competing interests.’’ The H. J.
Heinz Company Limited, provides technical expertise and in-kind contribution to
facilitate the production and technology transfer of Sprinkles as part of the
company’s Corporate Social Responsibility Program.
3To whom correspondence and reprint requests should be addressed.
0022-3166/06 $8.00 ? 2006 American Society for Nutrition.
Manuscript received 30 September 2005. Initial review completed 31 October 2005. Revision accepted 12 January 2006.
by guest on June 6, 2013
The study reported here investigated the concurrent ab-
sorption of zinc and iron from Sprinkles when added to a maize-
based complementary food, in a mixed population of anemic
and nonanemic young children. Using stable isotope tech-
niques, our primary objective was to determine whether there
was a difference in the absorption of zinc at 2 different doses
given as Sprinkles. Our secondary objective was to examine
whether zinc and ascorbic acid have an effect on the absorption
of iron from Sprinkles.
SUBJECTS AND METHODS
Study area, participants, and recruitment
The study was conducted from June to September 2002 in the field
study area for the Kintampo Health Research Centre located in the
Kintampo district of Ghana. The study protocol was approved by the
Research Ethics Committees at the Hospital for Sick Children
(Toronto, Canada), and Ghana Health Service Ethics Review Board
(Accra, Ghana). Verbal consent to conduct the study in the Kintampo
district was obtained from opinion leaders within the Kintampo
District. Written informed consent was obtained individually from the
mothers of the children before the start of the study.
To be included, children were required to be between 12 and 24 mo
of age, be ingesting at least one complementary food in addition to
breast milk, be free from major illness such as symptomatic malaria, be
afebrile, have a hemoglobin (Hb)4concentration $70.0 g/L and be
able to stay within the study area for the study period. Children found
to be febrile or severely anemic (Hb ,70.0 g/L) were treated at no
Study design and protocol
Eligible children were studied at the Kintampo Health Research
Centre on the mornings of d 1, 2, 3, and 17. Randomization was done
by using coded chips pulled from an opaque bag by the child’s mother.
Children were randomized as follows. 1) Low zinc (LoZn) group: 5 mg
of elemental zinc as67Zn-labeled zinc gluconate, combined with 50 mg
ascorbic acid (AA) and 30 mg of elemental iron as57Fe-labeled mi-
croencapsulated ferrous fumarate; 2) high zinc (HiZn) group: 10 mg of
elemental zinc as67Zn-labeled zinc gluconate, combined with 50 mg
AA and 30 mg of elemental iron as57Fe-labeled microencapsulated
zinc as zinc gluconate (standard food-grade) combined with 30 mg of
elemental iron as57Fe-labeled microencapsulated with no added AA.
Sprinkles in all groups were also formulated with the standard dose
of 300 mg retinol equivalents of retinol acetate vitamin A. All doses
were individually weighed into color-coded opaque Eppendorf tubes by
experienced laboratory personnel at the Hospital for Sick Children
(Toronto, Canada). Assignment of the group designation was revealed
only upon completion of the statistical analyses.
The higher dose of zinc (10 mg) was based on commonly used
dosages of zinc in supplementation trials in developing countries
involving young children (8–10). The lower dose of zinc (5 mg) was
based on the Recommended Dietary Allowance (11) for zinc in
children 12–24 mo of age. The total dose of elemental iron to be tested
(30 mg) was based on our previous bioavailability study conducted
among a similar population of children in Ghana (3).
After randomization (d 1), Hb was determined in each participant
and a heparinized venous blood sample (3 mL) was obtained.
Immediately after the blood sample was taken, a 10 mL [70Zn] sulfate
(0.5 mg zinc) i.v. infusion was administered through a 1.2-mm filter
over 5 min to children in Groups LoZn and HiZn. Similarly, a 20-mL
[58Fe]ferrous citrate (0.2 mg elemental iron) i.v. infusion was
administered to the control group as previously described (3). At the
end of the i.v. administration, the infusion sets were flushed with saline
to ensure that all of the i.v. tracers (70Zn or58Fe) were infused.
No food or liquids other than water and breast milk were allowed
for 4 h before the test meal administration. The test meal used
throughout the study was made from locally available foods as
previously described (3). All test meals to which the labeled Sprinkles
were added were given to the children on 2 consecutive days using the
same protocol as previously described (3). Samples from 11 test meals
were analyzed for phytic acid and iron; the phytate:iron molar ratio was
9.8 (Health Canada, Ottawa, Canada).
A finger prick blood sample (500 mL) was collected into
heparinized Microvette?tubes on d 3 (Sarstedt) from participants in
Groups LoZn and HiZn only. Fourteen days later (d 17), Hb was
determined and a final blood sample was collected from a finger prick
(500 mL) in all groups. Anthropometric measurements, including
weight and length, were completed as previously described (12). After
exclusion, withdrawal, or completion of the trial, all anemic children
(Hb ,100 g/L) were given a 2-mo supply of Sprinkles (12).
Stable isotope labels and dosing
Zinc stable isotopes. Zinc isotopes were purchased from Trace
Sciences International as oxide powder (67Zn at 82.0% enrichment)
and white oxide powder (70Zn at 95.56% enrichment). The oral [67Zn]
oxide powder was converted to [67Zn] gluconate by one of the major
commercial suppliers of zinc fortification compounds, Dr. Paul
Lohmann GmbH KG (Emmerthal, Germany). For the preparation of
[67Zn] gluconate, [67Zn] oxide was dissolved in demineralized water
The [70Zn] white oxide powder was converted to zinc sulfate at the
Hospital for Sick Children (Toronto, Canada) using sterile, pyrogen-
free equipment and aseptic techniques. For the preparation of [70Zn]
sulfate, the [70Zn] oxide powder was dissolved in trace element–free
sulfuric acid and the resulting precipitate dried. The [70Zn] sulfate
powder was then reconstituted with sterile saline to a70Zn-labeled
the solution was filtered through a 0.22-mm filter and stored in indi-
vidual sterile injection vials (10mL), which were purged withnitrogen,
sealed and kept refrigerated until use. The final solution was tested for
sterility and pyrogenicity before use. Total zinc concentration of the
final product was determined using inductively coupled plasma MS
Iron stable isotopes. Details on the iron isotopes (57Fe and58Fe)
used in this study including their origin, abundances, conversions,
microencapsulation of [57Fe]ferrous fumarate, dosages, and validation
were described elsewhere (3).
Whole blood samples collected at baseline (d 1) and on d 17 were
used to make thick blood smears and determine iron isotopic
composition of erythrocytes. At baseline, plasma was used to deter-
mine mass isotope zinc ratio (in groups LoZn and HiZn only), zinc
concentration, and soluble transferrin receptor concentration (sTfR).
On d 3, plasma was used for analysis of 48-h plasma zinc isotope ratios.
Hb and sTfR were measured as previously described (3). Malaria
smears were examined at the Noguchi Memorial Institute for Medical
Research, University of Ghana, Legon, using standard techniques.
Analysis of isotopic composition of blood samples
Zinc isotope analysis. Zinc isotope analysis was completed using
methods described by Serfass et al. (13) with minor modifications. The
inductively coupled plasma MS instrument (PlasmaQuad 3, TJA
Solutions) used to determine the zinc isotopes had the following
operating parameters: Plasma power, 1350 W; rest mass, 65.5 amu.;
nominal dwell masses, 66.0, 67.0, 70.0 amu; dwell time, 10 ms; points
per peak, 3; acquisition time, 18 s; replicate acquisitions, 10; ratios,
67:66, 70:66. A standard solution of yttrium (200 ng/L) in 0.15 mol/L
nitric acid was used to optimize the instrumental parameters, to
avoid contamination of the instrument with extraneous zinc. The
mean relative precision (percentage relative SD, n ¼ 28) obtained
for67Zn/66Zn ratio measurements was 1.18% and for70Zn/66Zn ratio
measurements was 1.22%.
4Abbreviations used: AA, ascorbic acid; DMT1, divalent metal transporter-1;
Hb, hemoglobin; HiZn, high zinc group; LoZn, low zinc group; min, minimum; max,
maximum; sTfR, soluble transferrin receptor; Zn, zinc.
ZINC AND IRON ABSORPTION FROM SPRINKLES
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Iron analysis. Iron isotope ratios were measured in the RBC 14 d
after administration, as previously described (3). Mean relative preci-
sion (percentage relative SD, n ¼ 72) obtained for57Fe/54Fe ratio mea-
surements was0.46%andfor58Fe/54Feratiomeasurements was0.56%.
Calculation of zinc and iron absorption
The percentage of zinc absorption was determined according to
O’Brien et al. (14). The degree to which the zinc isotope ratios differed
from baseline ratios was determined as follows:
The natural abundance ratios used for the
isotope ratios were 0.14779 and 0.02229, respectively.
The percentage of zinc absorption was determined by measuring
the ratio of the oral to the i.v. zinc label in plasma samples as follows:
The percentage of iron absorption from the administered dose was
calculated as described previously (3).
Sample size. Our sample size estimation was based on our primary
objective. Usingdata from our past work onzinc absorption from infant
cereal (unpublished), the SD of the percentage of zinc absorption was
estimated to be 4%. Based on an independent t test comparison, we
estimated that 17 children per group would have a power of 80% (a ¼
0.05) to reject the null hypothesis that the difference in percentage
zinc absorption between LoZn and HiZn groups was zero. The minimal
detectable difference was 4%. Assuming a 30% dropout rate, we
planned to recruit 22 children per group.
Statistical methods. Continuous data were examined with de-
scriptive statistics (means and SD) and histograms. When data were
skewed, log transformation and computed geometric means and ranges
were used. Binary data were summarized with frequency counts and
percentages. Hb and sTfR concentrations were dichotomized using
cut-off levels of ,100 g/L (3) and .8.5 mg/L (15,16), for anemia and
iron deficiency, respectively. Scatter plots (and correlation coeffi-
cients) were used to examine the relation between iron and zinc ab-
sorption values by anemia status.
Zinc absorption. Zinc absorption in the LoZngroup wascompared
with that of the HiZn group using a general linear model that had log-
transformed zinc absorption as the dependent variable and LoZn group
allocation as the independent variable. This model was extended to
adjust for any significant differences between groups including age,
gender, Hb, plasma zinc, sTfR, and malaria.
Effect of zinc and ascorbic acid on iron absorption. Using similar
general linear models that had log-transformed iron absorption values
as the dependent variable and LoZn group allocation as the in-
dependent variable, we compared the LoZn and HiZn groups to test for
the effect of zinc on iron absorption, and the LoZn and control groups
to test for the effect of AA on iron absorption. Again, we extended the
model to test for any potential confounding variables. We used Tukey’s
adjustment for multiple comparisons. For all calculations and analyses,
we used SAS, version 9.1 (SAS Institute).
Participant characteristics and hematological indices
Seventy-five children were screened and 60 completed the
study (Fig. 1). Reasons for exclusion included severe anemia
(Hb ,70 g/L), fever, and withdrawal. The i.v. infusions could
be administered to only 13 children in LoZn group, 15 children
in HiZn group, and 12 children in control group because of
difficulty in accessing veins in the rest of the participants. With
the exception of Hb, the 3 groups did not differ in character-
istics and hematological indices (Table 1). The prevalence of
iron deficiency varied from 71 to 80% across the 3 groups. The
number of children who tested positive for malaria was as
follows: 11 in the LoZn group, 4 in the HiZn group, and 7 in the
The final concentration of the
(after filtration) was 43.2 mg/L (86.4% of planned final
concentration). Zinc absorption is reported for the LoZn and
HiZn groups in which the participants received the i.v. infusion
(Table 2). The percentage of zinc absorbed did not differ,
whereas the total amount of zinc absorbed (mg) from the 2
doses was significantly different (P ¼ 0.0004).
70Zn-labeled i.v. infusion
FIGURE 1Trial profile.
ZLOTKIN ET AL
by guest on June 6, 2013
Effect of zinc and ascorbic acid on iron absorption
Information on the validation of the
infusion administered to the control group and on the cal-
culation of iron absorption was reported elsewhere (3). The
percentage and total amount of erythrocyte incorporation of
iron or iron absorbed between the LoZn and HiZn groups and
between the LoZn and control groups did not differ (Table 2).
Relation between iron and zinc absorption
The plot (Fig. 2) suggests that nonanemic children who
absorbed iron at a higher percentage also absorbed zinc at a
higher percentage and vice versa (r ¼ 0.68; P ¼ 0.01). There
was no relation between iron and zinc absorption in anemic
children (r ¼ 0.05; P . 0.05).
This study is the first to report the extent to which iron and
zinc are concurrently absorbed by young children when added
to a maize-based porridge as part of a home-fortification
strategy. The study population consisted of both anemic and
nonanemic young children most of whom were zinc replete
(based on a low prevalence of low plasma zinc concentrations).
The percentage of zinc absorption did not differ at the intakes
of 5 or 10 mg of zinc and there was no effect of zinc on iron
absorption. Similarly, the addition of ascorbic acid did not
increase iron absorption.
The absorption of the 2 different doses of zinc (5 and 10 mg)
provided as Sprinkles was somewhat lower than expected.
Geometric mean percentage zinc absorption was 6.4% (min-
max:1.7–14.6%) for the 5-mg dose and 7.5% (min-max: 3.3–
18.0%) for the 10-mg dose. There were no significant dif-
ferences in the percentage of absorption between the 2 zinc
doses although the total amount of zinc absorbed in the 10-mg
dose was significantly greater. Others reported similar low zinc
absorption values from fortified foods that included both iron
and zinc (17,18). However, it is difficult to compare our results
with those of others who used different forms and doses of iron
and zinc, different vehicles for fortification, and different study
Based on studies that demonstrated no effect on zinc
absorption from iron-fortified weaning cereals or infant formula,
Baseline characteristics and hematological indices of young
children provided with [57Fe] ferrous fumarate and/or
[67Zn] zinc gluconate as Sprinkles
Group LoZn HiZnControl
Plasma Zn, mmol/L
sTfR . 8.5 mg/L
21 21 18
17.2 6 4.1
77.0 6 5.1
9.6 6 1.4
16.8 6 3.0
75.7 6 4.2
9.0 6 1.3
15.4 6 6.0
76.5 6 4.7
8.9 6 1.0
21.5 6 11.0
94.6 6 8.6
21.2 6 9.4
102.9 6 12.2
17.6 6 6.7
99.6 6 15.7
1Values are means 6 SD or n (%).
Erythrocyte incorporation of Fe and Fe absorption in young children from [57Fe] ferrous
fumarate and Zn absorption from [67Zn] zinc gluconate ingested as Sprinkles1
Group LoZn HiZnControl
% of dose
Total Zn, mg
Erythrocyte incorporation of Fe
% of dose
% of dose
1315 Not measured
1Values are geometric means (min–max). Means in a row with different superscript letters differ, P
2Calculated on the assumption that the percentage incorporation of total Fe was identical to the
percentage incorporation of the57Fe label.
nonanemic young children provided with [57Fe] ferrous fumarate and
[67Zn] zinc gluconate as Sprinkles. Dashed line and circles represent
children with Hb , 100 g/L (n ¼ 15, r ¼ 0.05, P ¼ , 0.05). Solid line and
stars represent children with Hb $ 100 g/L (n ¼ 12, r ¼ 0.68, P ¼ 0.01).
Relationbetweenzinc and ironabsorptionin anemicand
ZINC AND IRON ABSORPTION FROM SPRINKLES
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or from iron supplements taken with food, we expected better
zinc absorption than we observed (19–22). Indeed, in 4 studies
in adults or young children, zinc absorption from fortified
iron food was between 25 and 40% (19,20,23,24). In addi-
tion, recent estimates of zinc absorption from typical diets
found in several developing countries including Ghana were
reported to be 30% (25); however, these foods had no added
iron. Similar to the inhibiting effect on iron, phytate was shown
to bind zinc and form insoluble complexes, thereby reducing its
absorption (26). However, given the relatively high absorption
of zinc from foods typically eaten in Ghana, a high phytate
content is not likely to be responsible for the low zinc
absorption observed in the current study (25). It is more likely
that the lower than expected zinc absorption values found
in the current study were a result of the relatively high iron
dose (30 mg), which was concomitantly added to the comple-
The effect of iron on zinc absorption could not be
investigated in the current study because only 1 iron dose
was administered. However, the high Fe:Zn molar ratios (7:1 in
Sprinkles containing 5 mg zinc and 3.5:1 in Sprinkles
containing 10 mg zinc) may have inhibited zinc absorption
through competition for a common absorptive pathway on
luminal intestinal mucosal cells. Indeed, it was demonstrated
that when both iron and zinc are provided at a Fe:Zn molar
ratio exceeding 2:1, the fractional absorption of zinc is sub-
stantially reduced (27). It is possible that there is absorptive
competition between iron and zinc on the divalent metal
transporter-1 (DMT1) (28). However, a recent review sug-
gested that zinc may not be transported by DMT1, and thus it is
unlikely that the DMT1 is a site of inhibition (29). The possible
mechanisms of zinc uptake remain to be determined (30).
Because the absorption efficiency (in terms of percentage)
did not differ between the 2 zinc doses, the higher dose resulted
in significantly more zinc being absorbed. Geometric mean total
zinc absorbed was 0.31 mg for the 5-mg zinc dose and 0.82 mg
for the 10-mg zinc dose. Comparing these absorbed values with
the requirement for absorbed zinc for children aged 1–3 y (0.74
mg/d for absorbed zinc), only the higher dose of zinc would be
expected to meet the requirements for absorbed zinc (11). The
lower dose would contribute ;42% of the absorbed zinc
requirement for children in this age group.
Similar to iron, there are several approaches for estimating
zinc absorption from foods or supplements. However, unlike
iron, studies on zinc absorption in young children using stable
isotopes are limited because zinc stable isotopes techniques are
still relatively novel (26). To date, studies investigating zinc
absorption in young children have involved collecting urine
and/or fecal samples when giving oral and i.v. isotopic zinc
doses (17,26,30–34). In the present study, it was not feasible to
collect urine samples with any accuracy. Therefore, we chose to
take plasma samples instead (35). One study in pregnant women
used a method similar to that described here (14).
The values for iron absorption reported here do not differ
considerably from those found in our previous study on iron
absorption from Sprinkles, done in a similar sample of young
children but without added zinc. These results support recent
evidence suggesting that zinc does not inhibit iron absorption
(29). However, a number of field trials of zinc and iron
supplementation suggested the opposite (8–10,23). These trials
demonstrated that the hemoglobin response to supplementary
iron is adversely affected by the concomitant addition of zinc to
the supplement. For example, a recent study using Sprinkles as
the vehicle to deliver micronutrients demonstrated a compro-
mise in the reduction in anemia prevalence with zinc 1 iron
compared with iron Sprinkles alone (10). Kordas and Stoltzfus
(29) speculated that the interaction between iron and zinc that
occurred in such supplementation trials may be postabsorptive.
Although we did not demonstrate an effect of ascorbic acid
on iron absorption in the current study, the promoting effect of
ascorbic acid and its ability to counteract the negative effects of
phytic acid on iron absorption have been well described (36).
However, there is limited and contradictory evidence using
ferrous fumarate as the iron source, and no studies have
evaluated the effect of ascorbic acid on iron absorption from
microencapsulated ferrous fumarate added to maize-based com-
plementary foods. Only 1 of 3 studies showed an increase in
iron absorption from ferrous fumarate with added ascorbic acid
at an ascorbic acid-iron molar ratio higher (4:1) than that used
in the current study (0.5:1) (6,7,37). The effect of ascorbic acid
on iron absorption should be further investigated.
Limited statistical power is the most common reason for not
for the lack of effect of ascorbic acid and zinc intake on iron
absorption. However, in a previous iron absorption study
conducted with Sprinkles, it was calculated that 17 children/
group would have 80% power to reject the hypothesis that the
(3). Thus, the current study appears to have adequate power.
Although the results of this study can be generalized to
countries in which maize-based complementary foods are the
norm, we do not know whether the absorption characteristics of
iron and zinc from Sprinkles would be similar in rice- or wheat-
based complementary foods with similar or lower amounts of
phytic acid. Despite the relatively low absorption of zinc,
Sprinkles with either 5 or 10 mg zinc would contribute substan-
tially to the absorbed zinc requirements for infants and young
children and would not compromise iron absorption. Future
research should explore the effect of other types of complemen-
tary foods on iron and zinc absorption from Sprinkles.
We gratefully acknowledge the dedicated and excellent fieldwork
provided by Hasia Adamu (Field supervisor), Victoria Adjei (Nutrit-
ion Rehablitation Ward Assistant), Sophia Nobabomg (Nutrition
Officer), Daniel Obeng (Clinical Nurse), Ophelia Poku (Field
supervisor), and Veronica Quartey (Nutrition Officer). We thank
Lisa Zeng and Kofi Tchum for their laboratory work and contribution
to the calculation of iron and zinc absorption. We thank Seeba
Amengo Eteego for his work on data management. We thank Dr.
S.P.J. Brooks and B.J. Lampi (Health Canada) for analyzing the
phytate content of the weaning food used in this trial. This research is
dedicated to the memory of Dr. Paul Arthur, colleague, friend, and
director of the Kintampo Health Research Centre.
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ZINC AND IRON ABSORPTION FROM SPRINKLES
by guest on June 6, 2013