Comparison of micronutrient-intake of lactating mothers from the Hlabisa district in KwaZulu-Natal using two different dietary intake methods
Date
2008-12
Authors
Herbst, Hendrina Carolina
Journal Title
Journal ISSN
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Publisher
Stellenbosch : Stellenbosch University
Abstract
INTRODUCTION: The objective of this research study was to analyze previously
collected dietary intake data using multiple 24-hour dietary recalls and semiquantitative
food frequency questionnaires (FFQ’s) in a group of HIV-positive and
HIV-negative breastfeeding women from a rural region in KwaZulu-Natal in order to
compare the intake of selective micronutrients obtained with the two instruments.
Identifying the pattern of food intake and the contribution of different foods to the
micronutrient intake in this population group will contribute to possible
recommendations aimed at dietary changes to improve dietary micronutrient intake.
This study was designed as a sub-study of a longitudinal prospective cohort study
and subjects (N=108) were lactating mothers enrolled in a cohort which investigated
the combined effect of HIV-infection and breastfeeding on women’s nutritional status.
METHOD: A locally constructed FFQ and 24h-recall were used to collect dietary
intake data from 108 subjects on three occasions, (~6 weeks, 14- and 24-weeks post
partum). Analysis was done using the Food Finder Program™2. Micronutrients under
investigation were iron, zinc, copper, selenium, vitamin A, B6, C, D and E, thiamin,
riboflavin and folic acid and were selected on their relevance in HIV (AIDS).
Descriptive statistics was used to determine the consumption of food items as
percentage of all food items consumed and to calculate mean, mode, median and
range of serving sizes for the ten food items most frequently consumed (measured
with the 24h and FFQ respectively). Data was not normally distributed (indicated by
the paired t-test and confirmed with a RM ANOVA nonparametric test). The F-value
was determined (using Wilcoxon matched pairs test) and the significance of the
difference between the micronutrient intakes measured with the two instruments
(p<0.05) calculated. To investigate the strength of the correlation between the two
dietary intake measures, Spearman’s correlation coefficients were determined for the
nutrients under investigation. The significance level for these measurements was
95% (p<0.05). RESULTS: Both methods identified maize meal and mahewu, bread, chicken, dried
beans, cabbage, onion, bananas, oranges and green leaves as the foods most often
consumed. Bread, dried beans, maas, pilchards, mango and green wild leaves were
the foods that contributed the most to the micronutrients under investigation. Although
maize meal (in the form of phutu or mahewu) was the food item most frequently
consumed in large portions, it was not in the top ten food items for any micronutrient
contribution, except for selenium. Correlation coefficients (unadjusted for energy) in
this study were very poor, ranging from 0.038 for vitamin B12 up to 0.48 for iron. All
correlations (except vitamin B12) were poor but significant (p<0.05).
CONCLUSION: There was some agreement found in the type of foods most
frequently consumed and their contribution to the micronutrient intake of this
population group, when using three 24h-recalls and FFQ’s and therefore in describing
the habitual food intake of the population group. There was however no agreement
between the micronutrient intake measured with three 24h-recalls and three FFQ’s
(p<0.05). Further analysis of the data and comparisons with the biochemical results
reported in another study, is recommended.
Description
Thesis (MNutr (Interdisciplinary Health Sciences. Human Nutrition))--Stellenbosch University, 2008.
Keywords
Dietary intake, Micronutrients, Food frequency, Lactation -- Nutritional aspects, Mothers -- Nutrition, Dissertations -- Nutrition, Theses -- Nutrition