Plasma zinc is an insensitive predictor of zinc status: use of plasma zinc in children with sickle cell disease.

BACKGROUND: This study was designed to explore the use of plasma zinc in determining zinc deficiency in children with sickle cell disease-SS (SCD-SS) as indicated by a growth response to zinc supplementation. METHODS: Fasting plasma zinc was assessed in children with SCD-SS (ages 4 to 10 years) who were randomly assigned to receive 10 mg zinc/d in cherry syrup (zinc) or cherry syrup alone (placebo) for 12 months. Evaluations for growth, dietary intake, and other biochemical parameters were made at baseline and 3, 6, and 12 months. Longitudinal mixed effects analysis evaluated differences between groups over 12 months. RESULTS: A total of 38 prepubertal children (20 male and 18 female; 18 zinc and 20 placebo) completed the study (7.1 +/- 1.7 years old). At baseline, plasma zinc was low (< or = 70 microg/dL) in 7 male subjects. Despite the significant increase in height over 12 months (+0.7 cm) with zinc supplementation (p = .019), plasma zinc did not change over the 12 months of study, and there was no association between plasma zinc and linear growth. Those children with low plasma zinc who received zinc supplementation showed improved linear growth. CONCLUSIONS: These findings suggest that plasma zinc is an insensitive indicator of zinc status in children with SCD-SS. Children with low plasma zinc will benefit from zinc supplementation. However, some children with normal plasma zinc and poor growth may also have growth-limiting zinc deficiency and exhibit a growth response to zinc supplementation. Although this study focused on children with SCD-SS, results may be generalized to other pediatric clinical illnesses where nutrition-related growth failure is investigated.     

Short-term supplementation with zinc and vitamin A has no significant effect on the growth of undernourished Bangladeshi children.

BACKGROUND: Several vitamin A supplementation trials have failed to improve the growth rate in children. Addition of zinc to vitamin A might result in enhanced growth. OBJECTIVE: This study evaluated the effect on growth in children of simultaneous supplementation with zinc and vitamin A. DESIGN: This was a randomized, double-blind, placebo-controlled intervention trial. Six hundred fifty-three children aged 12-35 mo were randomly assigned to 1 of 4 intervention groups: 20 mg Zn/d for 14 d (Z group), 60000 retinol equivalents (200000 IU) vitamin A on day 14 (A group), zinc plus vitamin A (ZA group), or placebo syrup and placebo capsule (placebo group). Weight and length were measured at enrollment and again after 3 and 6 mo. RESULTS: Gains in weight and length during the 6-mo follow-up period were not significantly different among the 4 groups by analysis of variance. Catch-up growth also did not differ significantly among the groups. The proportions of children whose weight-for-age z scores did not change or decreased were 57% in the Z group, 46% in the A group, 50% in the ZA group, and 54% in the placebo group (NS). The proportions of children whose length-for-age z scores did not change or decreased were 42% in the Z group, 48% in the A group, 53% in the ZA group, and 46% in the placebo group (NS). CONCLUSION: Combined short-term zinc supplementation and a single dose of vitamin A has no significant effects on weight and length increments in children over a 6-mo period.     

Spread fortified with vitamins and minerals induces catch-up growth and eradicates severe anemia in stunted refugee children aged 3-6 y

BACKGROUND: Multiple micronutrient deficiencies are often the basic causative factor in stunting and anemia, 2 conditions that affect entire generations of children in deprived populations. No generally accepted recommendations for micronutrient intakes for recovery from stunting are available. OBJECTIVE: The objective was to assess the effect of a highly nutrient-dense spread fortified with vitamins and minerals, with or without antiparasitic metronidazole treatment, in correcting retarded linear growth and reducing anemia in stunted children. DESIGN: Saharawi refugee children (n = 374) aged 3-6 y with initial height-for-age z scores <-2 were assigned to 1 of 5 groups: fortified spread (FS), fortified spread plus metronidazole (FS+M), unfortified spread (US), unfortified spread plus metronidazole (US+M), or control. Supervised supplementation was given daily for 6 mo. Weight, height, knee-heel length, hematologic indexes, parasitic infections, and morbidity were assessed at 0, 3, and 6 mo. RESULTS: Linear growth of children fed FS was 30% faster at 3 mo than in US and control groups, after which height-for-age z scores increased only slightly in the FS group and remained unchanged in the other groups. No additional benefits from metronidazole were observed. Increase in hemoglobin concentrations in the FS group at 6 mo was twofold that in the US and control groups (37 +/- 40, 19 +/- 15, and 16 +/- 17 g/L, respectively; P < 0.0001), and anemia was reduced by nearly 90%. CONCLUSIONS: FS, and not US, induces catch-up growth in stunted children whose diets are poor in micronutrients. Our trial provides support for delivering multiple micronutrients to reverse stunting and reduce anemia in children up to age 6 y.     

Effect of supplemental zinc on the growth and serum zinc concentrations of prepubertal children: a meta-analysis of randomized controlled trials

BACKGROUND: Multiple studies have been carried out to assess the effect of zinc supplementation on children's growth. The results of these studies are inconsistent, and the factors responsible for these varied outcomes are unknown. OBJECTIVE: Meta-analyses of randomized controlled intervention trials were therefore completed to assess the effect of zinc supplementation on the physical growth and serum zinc concentrations of prepubertal children. DESIGN: A total of 33 acceptable studies with appropriate data were identified by MEDLINE (National Library of Medicine, Bethesda, MD) searches and other methods. Weighted mean effect sizes (expressed in SD units) were calculated for changes in height, weight, weight-for-height, and serum zinc concentration by using random-effects models; factors associated with effect sizes were explored by meta-regression techniques. RESULTS: Zinc supplementation produced highly significant, positive responses in height and weight increments, with effect sizes of 0.350 (95% CI: 0.189, 0.511) and 0.309 (0.178, 0.439), respectively. There was no significant effect of zinc on weight-for-height indexes [weighted mean effect size: -0.018 (-0.132, 0.097)]. Zinc supplementation caused a large increase in the children's serum zinc concentrations, with an effect size of 0.820 (0.499, 1.14). Growth responses were greater in children with low initial weight-for-age z scores and in those aged >6 mo with low initial height-for-age z scores. CONCLUSIONS: Interventions to improve children's zinc nutriture should be considered in populations at risk of zinc deficiency, especially where there are elevated rates of underweight or stunting. The population mean serum zinc concentration is a useful indicator of the successful delivery and absorption of zinc supplements in children.     

Longitudinal measures of circulating leptin and ghrelin concentrations are associated with the growth of young Peruvian children but are not affected by zinc supplementation

BACKGROUND: Leptin, ghrelin, and insulin are hormonal regulators of energy balance and, therefore, may be related to growth during infancy. Zinc is essential for growth, and its growth effects may be mediated through these hormones. OBJECTIVE: We examined the effects of supplemental zinc on plasma leptin, ghrelin, and insulin concentrations among young children at risk of zinc deficiency and examined the relations between these hormones and physical growth. DESIGN: Children (n = 142) aged 6-8 mo were randomly assigned to receive 3 mg Zn/d as a supplement, in a fortified food, or as a placebo for 6 mo. Relations between hormones and anthropometric z scores, body composition, and growth rates were examined at baseline and 3 and 6 mo after the start of the intervention. RESULTS: No treatment group-related differences were found in plasma leptin, ghrelin, or glucose concentrations or in anthropometric z scores at 3 or 6 mo after the start of the zinc intervention. Neither plasma leptin nor ghrelin concentrations at baseline or 3 mo were predictive of subsequent changes in growth. However, changes in weight-for-age z scores over the two 3-mo time intervals were positively associated with subsequent leptin concentrations and inversely associated with subsequent plasma ghrelin concentrations. CONCLUSIONS: Supplemental zinc did not affect the children's growth, anthropometric indexes, or plasma hormone concentrations in this study population. Our results suggest that plasma leptin and ghrelin concentrations in later infancy are a consequence of previous weight changes rather than predictors of short-term growth.     

Synergistic effect of zinc and vitamin A on the biochemical indexes of vitamin A nutrition in children.

BACKGROUND: Zinc deficiency limits the bioavailability of vitamin A. Because zinc and vitamin A deficiency often coexist in malnourished children, simultaneous zinc and vitamin A supplementation may improve the vitamin A deficiency in these children. OBJECTIVE: A randomized, double-blind, placebo-controlled intervention trial was conducted to evaluate whether combining zinc and vitamin A supplementation would improve the biochemical indexes of vitamin A nutriture. DESIGN: Children aged 12-35 mo were randomly assigned to 1 of 4 intervention groups: 20 mg Zn/d for 14 d (Z group), 60000 retinol equivalents (200000 IU) vitamin A on day 14 (A group), zinc plus vitamin A (ZA group), or placebo syrup and placebo capsule (placebo group). Venous blood was drawn at enrollment and on day 21. RESULTS: Mean serum retinol concentrations were not significantly different between the A and ZA groups. Among vitamin A-deficient children, the proportion of children who remained vitamin A deficient (serum retinol <0.7 micromol/L) after supplementation was 40.6% in the Z group, 37.5% in the A group, and 47.0% in the placebo group; only 13.3% in the ZA group remained vitamin A deficient (P < 0.05 compared with the placebo group). The proportion of children whose retinol binding protein concentrations remained low was significantly lower in the ZA group than in the other groups (P < 0.05). CONCLUSION: Combined zinc and vitamin A supplementation improves vitamin A nutriture in vitamin A-deficient children.     

Impact of zinc supplementation on subsequent morbidity and growth in Bangladeshi children with persistent diarrhoea

This study was conducted to explore whether supplementation of zinc to children during persistent diarrhoea has any subsequent effect on morbidity and growth. A prospective follow-up study was conducted among children, aged 3-24 months, with persistent diarrhoea, who participated earlier in a double-blind randomized placebo-controlled trial. During persistent diarrhoea, children were randomly allocated to receive either zinc in multivitamin syrup or only multivitamin syrup for two weeks. After recovering from diarrhoea, 76 children in the multi-vitamin syrup and 78 children in the zinc plus multivitamin syrup group were followed up for subsequent morbidity and growth. Weekly morbidity and two-weekly anthropometric data were collected for the subsequent 12 weeks. Data showed that episodes and duration of diarrhoea were reduced by 38% and 44% respectively with supplementation of zinc. There was no significant difference in the incidence or duration of respiratory tract infection between the zinc-supplemented and the non-supplemented group. Improved linear growth was observed in underweight children (weight-for-age <70% of the National Center for Health Statistics standard) who received zinc compared to those who did not receive.     

Pregnancy and lactation hinder growth and nutritional status of adolescent girls in rural Bangladesh

Adolescent pregnancy is associated with adverse birth outcomes. Less is known about its influence on maternal growth and nutritional status. We determined how pregnancy and lactation during adolescence affects postmenarcheal linear and ponderal growth and body composition of 12-19 y olds in rural Bangladesh. In a prospective cohort study, anthropometric measurements were taken among primigravidae (n = 229) in the early first trimester of pregnancy and at 6 mo postpartum. Randomly selected never-pregnant adolescents (n = 458) of the same age and time since menarche were measured within 1 wk of these assessments. Annual changes in anthropometric measurements were compared between the 2 groups adjusting for confounders using mixed effects regression models. The mean +/- SD age and age at menarche of adolescents were 16.3 +/- 1.6 y and 12.7 +/- 1.2 y, respectively. Unlike pregnant girls who did not grow in height (-0.09 +/- 0.08 cm/y), never-pregnant girls increased in stature by 0.35 +/- 0.05 cm/y. The adjusted mean difference between the 2 groups was 0.43 +/- 0.1cm (P < 0.001). Similarly, whereas never-pregnant girls gained BMI, mid-upper arm circumference, and percent body fat, pregnant girls declined in every measurement by 6 mo postpartum, resulting in adjusted mean +/- SD differences in annual changes of 0.62 +/- 0.11 kg/m(2), 0.89 +/- 0.12 cm, and 1.54 +/- 0.25%, respectively (all P < 0.001). Differences in changes in all anthropometric measurements except height were greater among adolescents whose first pregnancy occurred <24 mo vs. > or =24 mo since menarche (BMI, -1.40 +/- 0.18 vs. -0.60 +/- 0.11 kg/m(2); all interaction terms, P < 0.05). Pregnancy and lactation during adolescence ceased linear growth and resulted in weight loss and depletion of fat and lean body mass of young girls.     

Long-term supplementation with iron does not enhance growth in malnourished Bangladeshi children.

To evaluate the effect of long-term oral iron supplementation on growth, 250 children aged 6-71 mo were studied in a randomized double-blind controlled trial. The intervention group received 125 mg of ferrous gluconate (15 mg elemental iron) plus multivitamins (vitamins A, D and C); the comparison group received only multivitamins daily for 12 mo. Weight (kg) and height (cm) were measured every month. Eighty three percent of the children continued the treatment for one year. The weight increment over the 12-mo period was 1.35 +/- 0.65 kg (mean +/- SD) in the intervention group and 1.39 +/- 0.54 kg in the comparison group. The height increments were 6.01 +/- 1.47 and 6.18 +/- 1.58 cm in the intervention and comparison groups, respectively. Mean weight and height increments did not differ; in an analysis stratified according to different age and nutritional categories, they also did not differ between the two groups, indicating that long-term iron supplementation does not increase growth in children.     

Vitamin A supplementation selectively improves the linear growth of indonesian preschool children: results from a randomized controlled trial

BACKGROUND: Vitamin A deficiency is associated with stunting and wasting in preschool children, but vitamin A supplementation trials have not shown a consistent effect on growth. OBJECTIVE: We examined the effect of vitamin A supplementation on height and weight increments among Indonesian preschool children. DESIGN: Data were obtained from a randomized, double-masked, placebo-controlled trial of rural Javanese children aged 6-48 mo. Children received 206000 IU vitamin A (103000 IU if aged <12 mo) or placebo every 4 mo. RESULTS: High-dose vitamin A supplementation modestly improved the linear growth of the children by 0.16 cm/4 mo. The effect was modified by age, initial vitamin A status, and breast-feeding status. Vitamin A supplementation improved height by 0.10 cm/4 mo in children aged <24 mo and by 0.22 cm/4 mo in children aged >/=24 mo. The vitamin A-supplemented children with an initial serum retinol concentration <0.35 micromol/L gained 0.39 cm/4 mo more in height and 152 g/4 mo more in weight than did the placebo group. No growth response to vitamin A was found among children with an initial serum retinol concentration >/=0.35 micromol/L. In non-breast-fed children, vitamin A supplementation improved height by 0.21 cm/4 mo regardless of age. In breast-fed children, vitamin A supplementation improved linear growth by approximately 0.21 cm/4 mo among children aged >/=24 mo, but had no significant effect on the growth of children aged <24 mo. CONCLUSION: High-dose vitamin A supplementation improves the linear growth of children with very low serum retinol and the effect is modified by age and breast-feeding.     

A randomized, community-based trial of the effects of improved, centrally processed complementary foods on growth and micronutrient status of Ghanaian infants from 6 to 12 mo of age.

BACKGROUND: Koko, a fermented maize porridge used as the primary complementary food in Ghana, has been implicated in the high prevalence of child malnutrition. Weanimix, a cereal-legume blend developed by the United Nations Children's Fund and the Ghanaian government, has been promoted as an alternative. OBJECTIVE: We evaluated the effect of feeding Weanimix and 3 other locally formulated, centrally processed complementary foods on the nutritional status of 208 breast-fed infants. DESIGN: Infants were randomly assigned to receive 1 of 4 foods from 6 to 12 mo of age: Weanimix (W), Weanimix plus vitamins and minerals (WM), Weanimix plus fish powder (WF), and koko plus fish powder (KF). Dietary and anthropometric data were collected regularly. Blood was collected at 6 and 12 mo of age to assess iron, zinc, vitamin A, and riboflavin status. Before and after the intervention, cross-sectional data on the anthropometric status of infants not included in the intervention (NI; n = 464) were collected. RESULTS: There were no significant differences between intervention groups in weight or length gain or in hemoglobin, hematocrit, transferrin saturation, plasma zinc, or erythrocyte riboflavin values between 6 and 12 mo of age. From 9 to 12 mo of age, z scores were lower in NI infants than in the combined intervention groups [at 12 mo: -1.71 +/- 0.90 compared with -1.19 +/- 0.93 for weight and -1.27 +/- 1.02 compared with -0.63 +/- 0.84 for length (P < 0.001 for both), respectively]. The percentage of infants with low ferritin values increased significantly between 6 and 12 mo of age in groups W, WF, and KF but not in group WM. Change in plasma retinol between 6 and 12 mo of age was significantly greater in group WM than in the other 3 groups combined (0.14 +/- 0.3 compared with -0.04 +/- 0.3 micromol/L, P = 0. 003). CONCLUSIONS: All 4 foods improved growth relative to the NI group. Infants fed WM had better iron stores and vitamin A status than those fed nonfortified foods.     

Body composition in children with sickle cell disease

BACKGROUND: Impaired growth, poor nutritional status, and delayed skeletal and sexual maturation are common in children with sickle cell disease (SCD), yet the nature of associated body-composition deficits has not been fully described. OBJECTIVE: The objective was to assess growth, nutritional status, and body composition in 36 African American children with type SS SCD (20 females and 16 males) and 30 healthy control children (15 females and 15 males) of similar age (5-18 y) and ethnicity. DESIGN: Height, weight, bone age, pubertal status, skinfold thickness, and arm circumference were assessed. Height and weight were converted to z scores by comparison with national reference data and skinfold-thickness measurements were converted to z scores by comparison with African American- specific reference data. Fat-free mass (FFM) and fat mass (FM) were estimated by using 4 methods. Prepubertal children, pubertal males, and pubertal females were analyzed separately. RESULTS: Relative to the control subjects and to a national sample, children with SCD had significantly lower z scores for weight, height, arm circumference, and upper arm fat and muscle areas. Relative skeletal maturation was significantly delayed. After adjustment for age, children with SCD had significantly lower FM (prepubertal children and pubertal males only) and FFM (all 3 groups). CONCLUSIONS: Children with SCD have impaired growth, delayed puberty, and poor nutritional status. Low z scores for upper arm fat area indicate deficits in fat (energy) stores, and low FFM coupled with low upper arm muscle area indicate muscle wasting and low protein stores. These body-composition abnormalities suggest that the nutritional needs of the African American children with SCD were not being met.     

Effect of zinc supplementation on growth in West African children: a randomized double-blind placebo-controlled trial in rural Burkina Faso

OBJECTIVE: To analyse the effects of zinc supplementation on growth parameters in a representative sample of young children in rural Burkina Faso. Design Randomized, double-blind, placebo-controlled efficacy trial. Setting Eighteen villages in rural northwestern Burkina Faso. Subjects In all, 709 children aged 6-31 months were enrolled; 685 completed the trial. Intervention Supplementation with zinc (12.5 mg zinc sulphate) or placebo daily for 6 days a week for 6 months. Outcomes Weight, length/height, mid-arm circumference, and serum zinc. RESULTS: In a representative subsample of study children, 72% were zinc-deficient at baseline. After supplementation, serum zinc increased in zinc-supplemented but not in control children of the subsample. No significant differences between groups were observed during follow-up regarding length/height, weight, mid-arm circumference, and z scores for height-for-age, weight-for-age, and weight-for-height. CONCLUSIONS: We conclude that zinc supplementation does not have an effect of public health importance on growth in West African populations of young children with a high prevalence of malnutrition. Multinutrient interventions are likely to be more effective.     

Preschool iron-folic acid and zinc supplementation in children exposed to iron-folic acid in utero confers no added cognitive benefit in early school-age

In Nepal, antenatal iron-folic acid supplementation improved aspects of intellectual, executive, and fine motor function among school-age children. We examined the impact of added zinc to the maternal antenatal supplement (M-IFAZn) and preschool supplementation from 12 to 36 mo with iron-folic acid (C-IFA) ± zinc (C-IFAZn) on cognitive outcomes compared to maternal iron-folic acid (M-IFA) alone. Children 7-9 y old (n = 780) who participated in early childhood micronutrient supplementation trial during 2001-2004 and whose mothers participated in an antenatal micronutrient supplementation between 1999 and 2001 were followed for cognitive assessments in 2007-2009. Using multivariate analysis of variance and adjusting for confounders, M-IFA with child supplementation (either C-IFA or C-IFAZn) did not impact scores on the tests of general intelligence (Universal Nonverbal Intelligence Test), and executive function (Stroop and go/no go tests) relative to the M-IFA alone. However, children in the C-IFAZn group had slightly lower scores on the backward digit span (-0.29, 95% CI: -0.55, -0.04) and Movement Assessment Battery for Children (1.33, 95% CI: 0.26, 2.40) relative to the referent group, whereas both C-IFA (-1.92, 95% CI: -3.12, -0.71) and C-IFAZn (-1.78, 95% CI: -2.63, -0.92) produced somewhat lower finger tapping test scores (fine motor skills). The combination of M-IFAZn and C-IFA or C-IFAZn did not lead to any outcome differences relative to M-IFA alone. Preschool iron-folic acid ± zinc to children exposed to iron-folic acid in utero or addition of zinc to maternal iron-folic acid conferred no additional benefit to cognitive outcomes assessed in early school age. The late timing of supplementation during preschool may explain the lack of impact of iron and/or zinc.     

Dose-response trial of prophylactic zinc supplements, with or without copper, in young Ecuadorian children at risk of zinc deficiency

BACKGROUND: Multiple studies have shown the benefits of zinc supplementation among young children in high-risk populations. However, the optimal dose and safe upper level of zinc have not been determined. OBJECTIVES: The objectives of this study were to measure the effects of different doses of supplemental zinc on the plasma zinc concentration, morbidity, and growth of young children; to detect any adverse effects of 10 mg supplemental Zn on markers of copper or iron status; and to determine whether any adverse effects are alleviated by providing copper with zinc. DESIGN: This randomized, double-masked, community-based intervention trial was conducted in 631 Ecuadorian children who were 12-30 mo old at baseline and who had initial length-for-age z scores <-1.3. Children received 1 of 5 daily supplements for 6 mo: 3, 7, or 10 mg Zn as zinc sulfate, 10 mg Zn + 0.5 mg Cu as copper sulfate, or placebo. RESULTS: The change in plasma zinc concentration from baseline was positively related to the zinc dose (P < 0.001). Zinc supplementation, including doses as low as 3 mg/d, reduced the incidence of diarrhea by 21-42% (P < 0.01). There were no other significant group-wise differences. CONCLUSIONS: Zinc supplementation with a dose as low as 3 mg/d increased plasma zinc concentrations and reduced diarrhea incidence in the study population. There were no observed adverse effects of 10 mg Zn/d on indicators of copper or iron status. The current tolerable upper level of zinc recommended by the Institute of Medicine should be reassessed for young children.     

Maternal zinc supplementation and growth in Peruvian infants

BACKGROUND: Little is known about how maternal zinc intake influences growth in utero and in postnatal life in humans. OBJECTIVE: We aimed to assess the effect of maternal zinc supplementation during pregnancy on infant growth through age 1 y. DESIGN: A double-blind, randomized controlled trial of prenatal zinc supplementation was conducted from 1995 to 1997 in Lima, Peru. Women (n = 1295) were enrolled at 15.6 +/- 4.6 wk gestation and assigned to receive daily supplements with zinc (15 mg Zn + 60 mg Fe + 250 microg folic acid) or without zinc (60 Fe + 250 microg folic acid) through pregnancy to 1 mo after delivery. At birth, 546 infants were followed for 12 mo to assess growth. Anthropometric measures of body size and composition were collected monthly, and morbidity and dietary intake surveillance was carried out weekly. RESULTS: No differences in maternal socioeconomic characteristics by treatment group or follow-up period were found. Infants born to mothers prenatally supplemented with zinc had significantly (P < 0.05) larger average growth measures beginning in month 4 and continuing through month 12. In longitudinal regression modeling, prenatal zinc was associated with greater weight (by 0.58 +/- 0.12 kg; P < 0.001), calf circumference (by 1.01 +/- 0.21 cm; P < 0.001), chest circumference (by 0.60 +/- 0.20 cm; P = 0.002), and calf muscle area (by 35.78 +/- 14.75 mm(2); P = 0.01) after adjustment for a range of covariates. No effect was observed for linear growth. CONCLUSION: Maternal zinc supplementation in this population was associated with offspring growth, which is suggestive of lean tissue mass accretion.     

Effects of zinc supplementation as adjunct therapy on the systemic immune responses in shigellosis

BACKGROUND: Zinc is lost during diarrheal diseases, and zinc deficiency induces intestinal morphology-altering inflammatory responses that zinc supplementation can correct. OBJECTIVE: We assessed the in vivo effect of zinc supplementation on systemic and mucosal responses in mildly to moderately malnourished (defined as <-1 but >-2 and <-2 but >-3 weight-for-height z scores, respectively, based on the National Center for Health Statistics growth reference) children with shigellosis. DESIGN: A double-blind placebo-controlled trial was conducted in Shigella flexneri-infected children aged 12-59 mo. Daily for 14 d, elemental zinc (20 mg) and multivitamins (vitamins A and D, thiamine, riboflavin, and nicotinamide) plus calcium were given at twice the US recommended dietary allowance to the zinc group (n=28), and multivitamins plus calcium were given to the control group (n=28). All subjects received standard antibiotic therapy. RESULTS: There was no significant interaction between zinc supplementation and time, but zinc supplementation showed a significant effect on serum zinc concentrations. With a >or=4-fold increase in serum shigellacidal antibody titers from baseline used as the cutoff, the proportion of children with shigellacidal antibody response was greater in the zinc group than in the control group (P<0.03). There was a significant (P=0.02) treatment x time interaction for the proportions of circulating CD20+ and CD20+CD38+ cells, which were higher on day 7 in the zinc group than in the control group (P<0.007). No effect was seen on histopathologic features or the expression of innate and inflammatory mediators in the rectum. CONCLUSION: Adjunct therapy with zinc during acute shigellosis significantly improved seroconversion to shigellacidal antibody response and increased the proportions of circulating B lymphocytes and plasma cells.     

Zinc supplementation and psychosocial stimulation: effects on the development of undernourished Jamaican children

BACKGROUND: Undernourished children have poor levels of development that benefit from stimulation. Zinc deficiency is prevalent in undernourished children and may contribute to their poor development. OBJECTIVE: We assessed the effects of zinc supplementation and psychosocial stimulation given together or separately on the psychomotor development of undernourished children. DESIGN: This was a randomized controlled trial with 4 groups: stimulation alone, zinc supplementation alone, both interventions, and control (routine care only). Subjects were 114 children aged 9-30 mo and below -1.5 z scores of the National Center for Health Statistics weight-for-age references who were recruited from 18 health clinics. Clinics were randomly assigned to receive stimulation or not; individual children were randomly assigned to receive zinc or placebo. The stimulation program comprised weekly home visits during which play was demonstrated and maternal-child interactions were encouraged. The supplementation was 10 mg Zn as sulfate daily or placebo. Development (assessed by use of the Griffiths Mental Development Scales), length, and weight were measured at baseline and 6 mo later. Weekly morbidity histories were taken. RESULTS: Significant interactions were found between zinc supplementation and stimulation. Zinc benefited the developmental quotient only in children who received stimulation, and benefits from zinc to hand and eye coordination were greater in stimulated children. Zinc supplementation alone improved hand and eye coordination, and stimulation alone benefited the developmental quotient, hearing and speech, and performance. Zinc supplementation also reduced diarrheal morbidity but did not significantly improve growth. CONCLUSION: Zinc supplementation benefits development in undernourished children, and the benefits are enhanced if stimulation is also provided.     

A randomized, placebo-controlled trial of the effect of zinc supplementation during pregnancy on pregnancy outcome in Bangladeshi urban poor

BACKGROUND: Maternal zinc supplementation has been suggested as a potential intervention to reduce the incidence of low birth weight in developing countries. To date, placebo-controlled trials have all been performed in industrialized countries and the results are inconsistent. OBJECTIVE: The objective of this study was to evaluate whether zinc supplementation in Bangladeshi urban poor during the last 2 trimesters of pregnancy was associated with pregnancy outcome. DESIGN: We conducted a double-blind, placebo-controlled trial in which 559 women from Dhaka slums, stratified by parity between 12 and 16 wk of gestation, were randomly assigned to receive 30 mg elemental Zn/d (n = 269) or placebo (n = 290). Supplementation continued until delivery. Serum zinc was estimated at baseline and at 7 mo of gestation. Dietary intake was assessed at baseline and anthropometric measurements were made monthly. Weight, length, and gestational ages of 410 singleton newborns were measured within 72 h of birth. RESULTS: At 7 mo of gestation, serum zinc concentrations tended to be higher in the zinc-supplemented group than in the placebo group (15.9 +/- 4.4 compared with 15.2 +/- 4.3 micromol/L). No significant effect of treatment was observed on infant birth weight (2513 +/- 390 compared with 2554 +/- 393 g; NS) or on gestational age, infant length, or head, chest, or midupper arm circumference. The incidence and distribution of low birth weight, prematurity, and smallness for gestational age also did not differ significantly after zinc supplementation. CONCLUSIONS: Supplementation with 30 mg elemental Zn during the last 2 trimesters of pregnancy did not improve birth outcome in Bangladeshi urban poor. These results indicate that interventions with zinc supplementation alone are unlikely to reduce the incidence of low birth weight in Bangladesh.     

补充酸奶对北京郊区学前儿童体格生长的影响

目的: 观察补充酸奶对3~5岁学前儿童体格发育和营养状况的影响。 方法: 选择北京郊区7所幼儿园的402名学龄前儿童(男217人,女185人),其身高和/或体重低于WHO推荐标准的均值。随机分为对照组和酸奶组,酸奶组每天补充1杯酸奶(125 g),每周补充5 d;对照组不补充;两组均保持正常饮食,持续9个月。每月测量儿童的身高、体重和上臂围,并记录儿童补充和出勤的情况;每3个月进行膳食调查和血生化指标检测。 结果: 酸奶组儿童膳食中钙、锌和维生素A的摄入水平较对照组明显提高,且补充9个月时血红蛋白(Hb)明显高于对照组。酸奶组儿童的身高在3 、6 和9个月内的增长值(1.90、3.83、5.43 cm)比对照组显著提高(1.77、3.64、5.24 cm),也高于WHO推荐的50 个月龄儿童参考标准。酸奶组儿童的体重在3、6和9个月内的增长值(0.70、0.98、1.42 kg)比对照组显著提高(0.49、0.80、1.20 kg),并与WHO推荐的50 个月龄儿童参考标准持平。结论: 3~5岁学龄前儿童补充9个月酸奶后,可以明显改善机体营养状况,增加体格生长速率。