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BACKGROUND: Zinc deficiency is prevalent in children in developing countries. Supplemental zinc provides therapeutic benefits in diarrhea. OBJECTIVE: We sought to measure the effect of supplemental zinc given with oral rehydration therapy during recovery from acute or persistent diarrhea. DESIGN: We conducted pooled analyses including all available published and unpublished randomized controlled trials of the effects of supplementary oral zinc in children aged <5 y with acute or persistent diarrhea. We used Cox survival regression analysis to evaluate the overall effect of zinc on continuation of diarrhea and possible differential effects in subgroups divided by sex, age, weight-for-height, and initial plasma zinc concentration. Dichotomous outcomes were analyzed by logistic regression. To assess the effects of excluding studies without original data from the pooled analyses, effect-size was estimated for all studies by using random-effects models. RESULTS: Zinc-supplemented children had a 15% lower probability of continuing diarrhea on a given day (95% CI: 5%, 24%) in the acute-diarrhea trials and a 24% lower probability of continuing diarrhea (95% CI: 9%, 37%) and a 42% lower rate of treatment failure or death (95% CI: 10%, 63%) in the persistent-diarrhea trials. In none of the subgroup analyses were the 2 subgroups of each pair significantly different from each other; however, in persistent diarrhea there tended to be a greater effect in subjects aged <12 mo, who were male, or who had wasting or lower baseline plasma zinc concentrations. CONCLUSION: Zinc supplementation reduces the duration and severity of acute and persistent diarrhea. Copyright © 2000 American Society for Clinical Nutrition [ABSTRACT FROM AUTHOR]

The prevalence of trace elements deficiencies, vitamin A deficiency, anemia, and their relationships were investigated in a cross sectional study involving 243 children aged from 12 to 72 months in rural Vietnam. Serum levels of copper, zinc, selenium and magnesium were determined by inductively coupled plasma mass spectrometer and that of retinol by high performance liquid chromatography. Hemoglobin concentration in whole blood was measured by the cyanmethemoglobin method. The prevalence of deficiencies in zinc, selenium, magnesium, and copper was 86.9%, 62.3%, 51.9%, and 1.7%, respec-tively. On the other hand, 55.6% were anemic and 11.3% had vitamin A deficiency. Deficiency in two or more micronutrient was found in 79.4% of the children. Parameters associated significantly with anemia were selenium deficiency (OR 2.80 95% CI 1.63-4.80, p = 0.0002) and serum retinol <1.05 numol/L (OR 1.83, 95% CI 1.10-3.05, p = 0.021). Magnesium deficiency (OR 3.09 95% CI 1.36-7.03) was found to be a risk factor for zinc deficiency and vice versa. The results indicate that micronutrient deficiencies are prevalent among preschool children in Vietnam. In addition, the results also demonstrate a strong relationship between selenium deficiency and anemia. Clearly, sustainable strategies are urgently required to overcome the problems in the country. [ABSTRACT FROM AUTHOR]

Breast milk is considered to be the best nutrient source for infants. However, nutritional compositions of breast milk in developing countries, especially among malnourished women, have not been fully investigated. This study aimed to assess nutritional status and nutrient composition of breast milk in lactating mothers in rural Vietnam. Sixty breastfeeding mothers at 6 to 12 mo postpartum, free from any medical disorder and/or medication, and not pregnant were randomly selected in Yen The, Bac Giang, Vietnam. Their nutritional status, breast milk concentration and dietary intakes were assessed. Among the study participants, anemia (39.0%) and low serum zinc concentration (55.4%) were frequently observed. Dietary assessment revealed lower intakes of iron (10.2+/-2.5 mg/d) and zinc (10.4+/-2.2 mg/d) than estimated requirements. The breast milk concentration of iron, zinc and copper was 0.43+/-0.15 mg/L, 0.56 (0.37, 0.82) mg/L and 0.19+/-0.05 mg/L, respectively. The breast milk concentration of iron, zinc and copper was not correlated to the serum concentration or dietary intakes. In conclusion, we uncovered a high prevalence of anemia and zinc deficiency in lactating mothers in rural Vietnam. The findings demonstrate a low breast milk zinc concentration among the participants, but need further investigation.

Objective: We investigated the prevalence of anemia and deficiency in trace elements in adolescent girls living in rural Vietnam., Methods: Two hundred forty-five adolescent girls 11-17 y of age from three schools in rural province of Ha Nam, Vietnam, were assessed., Results: The prevalence of anemia was 20.4%. The incidences of low serum selenium (Se), zinc, and copper in subjects were 15.9%, 26.5%, and 4.1%, respectively. The parameter significantly associated with anemia was the low serum levels of Se and vice versa (odds ratio [OR] 5.36, 95% confidence interval [CI] 2.57-11.18, P < 0.0001). Other risk factors for anemia were a body mass index <17.00 kg/m(2) (OR 2.72, 95% CI 1.37-5.37, P = 0.004) and years of age (OR 1.35, 95% CI 1.14-1.59, P < 0.001). A body mass index <17.00 kg/m(2) (OR 2.65, 95% CI 1.25-5.61, P = 0.011) was also found to be a risk factor for low serum Se., Conclusion: The findings of the present study demonstrate that low serum Se is independently associated with anemia in adolescent girls living in rural Vietnam. Interventions are required to gain insight into the potential role of Se on prevention and control of anemia.

A cross-sectional study of 292 primary school children was conducted in rural Vietnam to investigate the relationship among micronutrient deficiencies, and other risk factors for anemia. Serum levels of iron, copper, zinc, selenium and magnesium were determined by inductively coupled plasma mass spectrometry and that of retinol by high performance liquid chromatography. Hemoglobin concentration in whole blood was measured by the cyanmethemoglobin method. The incidence of low serum zinc, selenium, magnesium, and copper in the children was 91.4, 75.6, 59.5, and 8.6%, respectively. Forty-five percent of the children were anemic and 11.3% suffered from vitamin A deficiency. A parameter significant associated with anemia was low serum selenium and vice versa (OR 1.85, 95% CI 1.06-3.24, p<0.05). Other factors associated with anemia were serum retinol <1.05 micromol/L (OR 2.05, 95% CI 1.25-3.36, p<0.01), and age in years (OR 1.59, 95% CI 1.16-2.18, p<0.01). The study showed that low selenium is associated with anemia among school children in Vietnam. Interventions are required to gain insight into the potential role of selenium on prevention and control of anemia.

Data from 4 randomized, placebo-controlled, double-blind trials in Indonesia, Thailand, and Vietnam, the South-East Asian Multicountry Trial on Iron and Zinc supplementation in Infants (SEAMTIZI), were pooled to investigate the effects of iron and zinc supplementation infant growth. Infants (n = 2451) aged 4-6 mo old were supplemented with iron (10 mg/d) and/or zinc (10 mg/d) for 6 mo. Overall, neither iron nor zinc supplementation prevented the progressive growth faltering during infancy, which is common in many developing countries. However, infants who received zinc were less likely to be stunted at the end of the supplementation period (odds ratio 0.80; 95% CI 0.64-1.0). Boys had a 30% higher risk of being stunted at the end of the study than girls (P < 0.01). Baseline factors modified the effect of supplementation, with infants anemic at baseline (hemoglobin < 105 g/L) benefiting from zinc supplementation, with an estimated increase in height-for-age Z-score (HAZ) score of 0.17 (P < 0.01), but with no effect of zinc supplementation on growth in infants not anemic at baseline. Iron supplementation negatively affected linear growth in infants with a birth weight of >3500 g (estimated effect size, -0. 14 HAZ score; P < 0.01), but with no significant effect in infants with a lower birth weight. This study shows that blanket supplementation of infants with iron or zinc will not be beneficial to all recipients and may have adverse effects in some. Hence, interventions such as iron and zinc supplementation for infants should be restricted to subgroups in which there is a clear benefit and baseline factors should be considered and characterized before implementing new policies.

The prevalence of trace elements deficiencies, vitamin A deficiency, anemia, and their relationships were investigated in a cross sectional study involving 243 children aged from 12 to 72 months in rural Vietnam. Serum levels of copper, zinc, selenium and magnesium were determined by inductively coupled plasma mass spectrometer and that of retinol by high performance liquid chromatography. Hemoglobin concentration in whole blood was measured by the cyanmethemoglobin method. The prevalence of deficiencies in zinc, selenium, magnesium, and copper was 86.9%, 62.3%, 51.9%, and 1.7%, respectively. On the other hand, 55.6% were anemic and 11.3% had vitamin A deficiency. Deficiency in two or more micronutrient was found in 79.4% of the children. Parameters associated significantly with anemia were selenium deficiency (OR 2.80 95% CI 1.63-4.80, p=0.0002) and serum retinol<1.05 micromol/L (OR 1.83, 95% CI 1.10-3.05, p=0.021). Magnesium deficiency (OR 3.09 95% CI 1.36-7.03) was found to be a risk factor for zinc deficiency and vice versa. The results indicate that micronutrient deficiencies are prevalent among preschool children in Vietnam. In addition, the results also demonstrate a strong relationship between selenium deficiency and anemia. Clearly, sustainable strategies are urgently required to overcome the problems in the country.

Deficiencies of iron and zinc are prevalent worldwide. Interactions between these micronutrients therefore have important consequences, also for supplementation. To investigate effects on hemoglobin and zinc concentrations and interactions of iron and zinc supplementation in infants, data from 4 parallel, randomized, placebo-controlled, double-blind trials in Indonesia, Thailand, and Vietnam were pooled. Infants (n=2468), aged 4-6 mo, were supplemented daily with iron (10 mg) and/or zinc (10 mg) for 6 mo. At 3 sites, infants were given vitamin A capsules (VAC) at recruitment. Combined supplementation reduced prevalences of anemia by 21% (P<0.01) and zinc deficiency by 10% (P<0.05) but was less effective (P<0.05) than supplementation with either iron (28% reduction in anemia) or zinc alone (18% reduction in zinc deficiency). Iron reduced the effect of zinc supplementation (interaction P<0.01), but had no separate effect on zinc status, whereas zinc supplementation had a negative effect on hemoglobin concentrations (-2.5 g/L, P<0.001), independent of iron supplementation (Pinteraction=0.25). The effect of iron supplementation on hemoglobin concentrations was almost twice as large in boys than in girls (effect size 12.0 vs. 6.8 g/L, respectively). In infants not receiving iron, VAC administration tended to be associated with lower (3.2%, P=0.07) hemoglobin concentrations. Combined supplementation of iron and zinc was safe and effective in reducing the high prevalences of anemia and iron and zinc deficiencies. Zinc supplementation may negatively affect iron status but iron supplementation does not seem to affect zinc status. Furthermore, VAC administration in the absence of iron supplementation may increase the incidence of anemia.

The objective of the study was to assess the prevalence of sub clinical vitamin A deficiency and anemia in Vietnamese children. For this, a cross-sectional survey was conducted in 40 villages (clusters) of four ecological regions in Vietnam during Apr-May 2001. In total 1657 children less than 5 years old were included by a cluster random sampling method. The prevalence of sub clinical vitamin A deficiency (serum retinol <0.70 mumol/l) was 12.0% and the prevalence of anemia (hemoglobin <110g/l) was 28.4 %. 35.1%. In the children under 6 months the prevalence of sub clinical vitamin A deficiency was 35.1 % whereas the prevalence of anemia in this group was as high as 61.7%. The prevalence of children with both sub clinical vitamin A deficiency and anemia was 6.1%. Sub clinical vitamin A deficiency and anemia prevalence differed significantly across the regions, with highest prevalence in the Northern Mountainous areas for vitamin A deficiency and in the Northern Mountainous area and Mekong River Delta for anemia. It is concluded that sub clinical vitamin A deficiency and anemia are still important public health problems in Vietnam. Sustainable strategies for combating vitamin A deficiency and nutritional anemia are needed and should concentrate on target groups, especially infants and malnourished children in high risk regions.

This study was aimed at assessing the serum levels of vitamin A, copper, zinc, selenium, and iron among adult Vietnamese with and without iron-deficiency anemia. Blood was collected from adult Vietnamese living in the midland of northern Vietnam. One hundred twenty-three subjects in the age range 20-60 yr were included in the study. Anemia, where the concentration of hemoglobin in whole blood is less than 120 g/L in females and 130 g/L in males, was found in 30% (37/123) of the study population. The levels of vitamin Aand selenium in the sera of anemic subjects (n = 37) were significantly lower than that in nonanemic group (n = 86). On the other hand, no significant differences were observed in the concentrations of copper and zinc between the two groups. This study was the first to show serum levels of trace elements in adult Vietnamese, providing useful baseline information for further studies.

Objective: To evaluate the effect of combined iron-zinc supplementation on micronutrient status, growth and morbidity., Design: Randomized, double-masked, placebo-controlled supplementation trial., Setting: Rural district of Que Vo, in the Red River Delta in Vietnam., Subjects: A total of 915 breast-fed infants aged 4-7 months were included and 784 completed the study., Interventions: The Fe-group received daily and for a 6-month period 10 mg of iron, the Zn-group 10 mg zinc, the Fe-Zn group 10 mg iron+10 mg zinc and the placebo group a placebo. Hemoglobin (Hb), serum ferritin (SF) and zinc (SZn), and anthropometry were measured before and at the end of the intervention. Morbidity was recorded daily., Results: Changes of Hb and SF were higher in both Fe and Fe+Zn groups (respectively 22.6 and 20.6 g/l for Hb; 36.0 and 24.8 microg/l for SF) compared to Zn and placebo groups (Hb: 6.4 and 9.8 g/l; SF: -18.2 and -16.9 microg/l, P<0.0001). SZn increased more in Zn group (10.3 micromol/l) than in Fe+Zn group (8.0 micromol/l, P=0.03) and more in these groups compared to Fe and placebo groups (1.6 and 1.2 micromol/l, P<0.0001). Weight gain was higher in the Zn group. No significant effects of supplementations on growth in length or morbidity., Conclusions: Combined iron-zinc supplementation had a positive effect on iron and zinc status in infants. However, the positive effect of zinc alone on SZn and weight would indicate a negative interaction of iron when added to zinc supplements., Sponsorship: UNICEF New York.

Objectives: This study assessed the effects of zinc supplementation in the prevention of diarrhea and pneumonia with the use of a pooled analysis of randomized controlled trials in children in developing countries., Study Design: Trials included were those that provided oral supplements containing at least one half of the United States Recommended Daily Allowance (RDA) of zinc in children <5 years old and evaluated the prevention of serious infectious morbidity through household visits. Analysis included 7 "continuous" trials providing 1 to 2 RDA of elemental zinc 5 to 7 times per week throughout the period of morbidity surveillance and 3 "short-course" trials providing 2 to 4 RDA daily for 2 weeks followed by 2 to 3 months of morbidity surveillance. The effects on diarrhea and pneumonia were analyzed overall and in subgroups defined by age, baseline plasma zinc concentration, nutritional status, and sex. The analysis used random effects hierarchical models to calculate odds ratios (OR) and 95% CIs., Results: For the zinc-supplemented children compared with the control group in the continuous trials, the pooled ORs for diarrheal incidence and prevalence were 0.82 (95% CI 0.72 to 0.93) and 0.75 (95% CI 0.63 to 0.88), respectively. Zinc-supplemented children had an OR of 0.59 (95% CI 0.41 to 0.83) for pneumonia. No significant differences were seen in the effects of the zinc supplement between the subgroups examined for either diarrhea or pneumonia. In the short-course trials the OR for the effects of zinc on diarrheal incidence (OR 0.89, 95% CI 0.62 to 1.28) and prevalence (OR 0.66, 95% CI 0.52 to 0.83) and pneumonia incidence (OR 0.74, 95% CI 0.40 to 1.37) were similar to those in the continuous trials., Conclusions: Zinc supplementation in children in developing countries is associated with substantial reductions in the rates of diarrhea and pneumonia, the 2 leading causes of death in these settings.

To determine the role of reduced liver GH binding (GHR) in the decreased IGF-I observed in zinc-deficient (ZD) animals, we investigated the effects of GHR restoration on growth, insulin-like growth factor I (IGF-I) and its binding proteins (IGFBPs) in ZD rats. Rats were fed for 4 weeks a zinc-deficient diet (ZD Zn, 0 ppm) or a Zinc-normal diet (pair-fed or PF; Zn, 75 ppm). ZD rats received continuous s.c. infusion of bovine growth hormone (bGH) (100 microg/d) for the 4 weeks or for the last week of the study. Compared with pair-fed rats, zinc deficiency produced attenuated weight gain (-43%, P < 0.001), lower serum IGF-I and liver IGF-I mRNA (-52%, P < 0.001 and -44%, P < 0.05), lower serum IGFBPs (IGFBP-3 -66%, IGFBP-4 -48%, 34-29 kDa IGFBP cluster -53%, P < 0.05), lower liver GHR and its mRNA (-20 and -34%, P < 0.05) and lower serum growth hormone binding protein (GHBP) and its mRNA (-56 and -48%, P < 0.05; all comparisons vs PF rats). Exogenous bGH given continuously normalized the liver GHR, serum GHBP and their liver mRNAs, as well as circulating IGFBPs. Despite restoration of GHR and GHBP to normal, growth, serum IGF-I and its liver mRNA were not stimulated by GH infusion in ZD rats, indicating that IGF-I synthesis requires the presence of zinc in addition to GH, and that the lack of growth-promoting action of GH in zinc-deprived rats results from a defect beyond GH binding to its liver receptors.

Zinc depletion attenuates growth and decreases circulating IGF-I. To investigate the mechanisms responsible for the IGF-I decline, we determined the effects of dietary zinc (Zn) deficiency on body and organ growth, serum IGF-I, serum GH-binding protein (GHBP), liver GH receptors and liver expression of their corresponding gene. After 1 week of adaptation to a normal zinc diet, a zinc-deficient diet (ZD; Zn, 0 p.p.m.) or a zinc-normal diet (CTR; Zn, 75 p.p.m.) was available ad libitum to 4-week-old Wistar rats for 4 weeks. Pair-fed animals (PF) received the zinc-normal diet in the same absolute amount as that consumed the day before by the ZD group. The food intake of ZD and PF rats was reduced by 32% (P < 0.001) compared with the CTR group. Zinc depletion specifically reduced body weight gain (-22%, P < 0.05), serum IGF-I concentrations (-52%, P < 0.001), hepatic GH receptors (-28%; P < 0.05) and serum GHBP levels (-51%; P < 0.05), compared with the PF group. GH concentrations were reduced in ZD animals compared with CTR rats (P < 0.01). The caloric restriction of PF animals also decreased body weight gain (-50%, P < 0.001), serum IGF-I concentrations (-21%, P < 0.05), liver GH receptors (-38%, P < 0.001) and serum GHBP levels (-38%, P < 0.01), when compared with the CTR group. Both ZD and PF groups had reduced liver IGF-I and GH receptor/GHBP mRNA levels in comparison with the CTR group (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)