Is zinc a limiting nutrient in the diets of rural pregnant Malawian women?

Abstract

Pregnant women consuming plant-based diets are at risk of Zn deficiency; Zn requirements for fetal growth and maternal tissue accretion are high. Therefore we have studied, at 24 and 33 weeks gestation, the Zn status of eighty-seven pregnant rural Malawian women (mean age 22.7 years) who consume maize-based diets, using anthropometry, dietary intake data, plasma and hair Zn concentrations, and infection status via serum C-reactive protein, leucocyte count, and malaria blood smear. Of the women, 12 % were stunted (height-for-age Z score < -2 SD ) and 20 % lost weight over the 9-week period; weight gain averaged 0.13 kg/week. Mean plasma Zn concentration declined significantly from 24 to 33 weeks (7.9 (SD 2.2) v. 6.6 (SD 2.0) pmol/l; P < 0.0003). Both plasma and hair Zn values were very low; nearly 50 % of the women had both plasma and hair Zn values below acceptable cut-off values. No significant differences in biochemical Zn indices existed between those who tested positive and negative for infection. Cereals (mainly maize) provided more than two-thirds of mean energy intake compared with less than 5 % from flesh foods. As a result about 60 % of the subjects had dietary phytate : Zn molar ratios greater than 15, and more than 35 % had inadequate Zn intakes based on probability estimates and WHO basal requirements. Biochemical evidence of Zn deficiency was attributed in part to low intakes of poorly available Zn. The anthropometric, biochemical, and dietary data together indicate that Zn deficiency may be a factor limiting pregnancy outcome in rural Malawian women.

The impact of malarial infection and diet on the anaemia status of rural pregnant Malawian women

“…Details of our validated interactive 24-h recall procedure, carried out on each woman in their own homes for three non-consecutive days, have been published earlier (Ferguson et al, 1995;Huddle et al, 1998). Food consumption data were used in conjunction with our previously compiled Malawian food composition table (based on analysed and literature values) to characterise the average intakes of energy, protein, protein from animal sources, iron, calcium, vitamin C, haem and non-haem iron, dietary ®bre (as nonstarch poly-saccharide), and phytic acid per day and per MJ.…”

A High Prevalence of Zinc- but not Iron-Deficiency among Women in Rural Malawi: a Cross-Sectional Study

“…After recruitment, the women were interviewed in their homes by trained research assistants using a pretested questionnaire to obtain demographic and socio-economic data, and information on the health and family characteristics of the women. From these data, a socio-economic status (SES) index was developed based on a total possible maximum score of 14 [15].…”

Snacks are important for fat and vitamin intakes among rural African women: a cross-sectional study from Malawi

“…Firstly, our study was conducted between March and May which is the peak season for orange, tangerine and most green leafy vegetables. This was reflected in a high proportion of women consuming these foods and higher intakes of vitamin A and vitamin C compared to previously reported intakes among women in Southern Malawi (Ferguson et al, 1995;Huddle et al, 1998;Nyambose et al, 2002). The importance of seasonality needs to be acknowledged as foods such as orange, tangerine, groundnut, pumpkin and avocado are not available throughout the year.…”

“…The non-staple foods which are eaten in small amounts with the staples at the main meals as well as snacks, eaten in between meals, are important for the contribution of essential nutrients, in particular vitamins and minerals. In areas where maize constitutes the majority of the food consumed, it contributes more than 70% of the energy and 60% of the protein intakes (Ferguson et al, 1995;Brouwer et al, 1996;Huddle et al, 1998). It has been shown that women in Southern Malawi have the above food consumption pattern and eat a monotonous diet with an average of less than seven foods per day, of which two, on average are snacks (Ferguson et al, 1995).…”

“…It has been shown that women in Southern Malawi have the above food consumption pattern and eat a monotonous diet with an average of less than seven foods per day, of which two, on average are snacks (Ferguson et al, 1995). A high percentage of these women are at risk of inadequate energy, protein, calcium, iron and zinc intakes (Ferguson et al, 1995;Brouwer et al, 1996;Huddle et al, 1998).…”