The need for maternal zinc supplementation in developing countries: an unresolved issue

Comparison of zinc levels in mothers with and without abortion: A systematic review and meta-analysiss

Introduction

Zinc is an essential trace element involved in different physiological functions. During pregnancy, it plays a crucial role in healthy embryogenesis. Abortion is the most severe problem associated with early pregnancy complications. This study aims to compare the levels of Zn in mothers with and without abortion.

Methods

This study is a systematic review and meta-analysis of studies published between 1980 and 2022 in PubMed, Science Direct, Pro Quest, Wiley, Web of Science, and Scopus databases. The search was conducted using both main and Mesh keywords, specifically targeting terms related to abortion, pregnancy loss, and zinc. Heterogeneity in the studies included in the meta-analysis was evaluated using statistical tests such as the chi-square test, I2, and forest plots. Publication bias was assessed using Begg's and Egger's tests. All analyses were conducted using Stata 15, and statistical significance was considered at p < 0.05.

Results

In general, nine studies were included in this analysis. Based on the results of the meta-analysis, the mean difference in the Zn level between mothers with and without abortion is equal to 193.18 (95 % CI; 107.11 to 279.25, P ≤ 0.001). In other words, the level of Zn in the group of mothers without abortion is 193 units higher than the group of mothers with abortion. The investigation into the comparison of Zn levels in mothers with and without abortion did not reveal any indication of publication bias according to both Begg's test (P-value = 0.858) and Egger's test (P-value = 0.270).

Conclusion

the study findings indicate a significant association between lower levels of Zn in mothers with abortion compared to mothers without abortion. This suggests that a higher level of Zn may have a preventive effect on the occurrence of abortion in pregnant women. The data also highlights the positive role of trace metals, particularly Zn, in influencing pregnancy outcomes and suggests that maintaining adequate levels of Zn may reduce the likelihood of abortion occurrence, along with other contributing factors. It is important to note that further research, including prospective cohort and experimental studies, is needed to provide more substantial evidence and strengthen these findings.

Effect of antenatal micronutrient or antidepressant exposure on Brazelton neonatal behavioral assessment scale (NBAS) performance within one-month of birth

BACKGROUND

Antenatal depression is a risk factor for poor infant outcomes. Broad-spectrum-micronutrients (vitamins and minerals) have shown efficacy in treating psychiatric symptoms in non-pregnant populations and are associated with reduced incidence of adverse birth outcomes, and improvements in neonatal development. We investigated the effects of treatment of antenatal depression with micronutrients above the Recommended Dietary Allowance on infant development compared to treatment with antidepressant medications and controls.

METHOD

One-hundred-and-three infants were assessed using the Brazelton Neonatal Behavioral Assessment Scale (NBAS) within 28 days of birth: 37 exposed to micronutrients in-utero (50-182 days exposure), 18 to antidepressants in-utero (exposure for full gestation), and 48 controls whose mothers received neither treatment nor experienced depressive symptoms.

RESULTS

Controlling for gestational age and parity, there were significant group differences on habituation, orientation, motor, state regulation, autonomic stability and reflexes (p < .05). Micronutrient-exposed performed better than antidepressant-exposed and controls on habituation, motor and autonomic stability (p < .05), effect sizes ranged 1.0-1.7 and 0.5-1.0, respectively. Antidepressant-exposed performed significantly worse on orientation and reflexes compared to micronutrient-exposed and controls. Micronutrient-exposed had significantly better state regulation compared to antidepressant-exposed. There was an association between micronutrient exposure length and better habituation (r = 0.41, p = .028). Micronutrient exposure was generally identified as a stronger predictor of neonatal performance over maternal depression, social adversity, gestational age and infant sex.

CONCLUSION

In-utero micronutrient exposure appears to mitigate risks of depression on infant outcomes showing positive effects on infant behavior, on par with or better than typical pregnancies and superior to antidepressants. Limitations include differential exposure to micronutrients/antidepressants and lack of group blinding.

Development of a Functional Dark Chocolate with Baobab Pulp

In recent years, cocoa and dark chocolate have attracted the interest of consumers not only for their sensory characteristics but also for their nutritional properties and positive impact on health. The baobab is a fruit of African origin with a sour and slightly sweet flavour, widely consumed by local communities due to its unique nutritional features. The aim of this work was to evaluate the impact of the concentration of baobab flour in the development of functional dark chocolate, including physical, chemical, nutritional and sensory evaluations. The results presented a positive correlation between the incorporation of baobab flour and the antioxidant activity (up to 2297 mmol TE/100 g), vitamin C content (up to 49.7 mg/100 g), calcium (up to 1052 mg/kg), potassium (up to 10,175 mg/kg), phosphorus (up to 795.9 mg/kg), chlorine (up to 235.4 mg/kg) and sulphur (up to 1158 mg/kg). The sensory evaluation of dark chocolate with 3% baobab presented the highest evaluation on the parameters "texture" and "overall flavour", while the parameter "overall flavour" presented the lowest evaluation on chocolate with 9% baobab. No influence was observed on fatty acid profile, protein, fat and hardness.

Some Immune Parameters of Term Newborns at Birth Are Associated with the Concentration of Iron, Copper and Magnesium in Maternal Serum

The nutritional status of pregnant women is considered to affect fetal development and the health condition of newborns, including their immune system. We investigated the relationship between the concentrations of magnesium (Mg), calcium (Ca), zinc (Zn), iron (Fe) and copper (Cu) in maternal serum (MS) and the concentrations of IgG antibodies and antineutrophil cytoplasmatic auto-antibodies against lactoferrin (Lf-ANCA) in umbilical cord serum (UCS). IgG was considered as a promoter of immunity, and Lf-ANCA as an inhibitor. The examined group consisted of 98 pregnant women and their healthy term newborn children. The concentrations of mineral elements were measured by FAAS/FAES, while the concentrations of antibodies were determined by ELISA. Excessive MS Fe and insufficient MS Cu were related to insufficient UCS IgG and excessive UCS Lf-ANCA. The correlation analysis showed confirming results. Adequate UCS IgG and Lf-ANCA were related to MS Mg at the strictly lower limit of the reference values. The results obtained seem to suggest that an excess of Fe and a deficiency of Cu in pregnancy may adversely affect some immune parameters of newborns. Reference values for MS Mg are likely to require reconsideration. It would be advisable to monitor the nutritional status of pregnant women with minerals in order to support the immune capacity of newborns.

Interrelated Effects of Zinc Deficiency and the Microbiome on Group B Streptococcal Vaginal Colonization

Group B Streptococcus (GBS) in the vaginal tract is a risk factor for preterm birth and adverse pregnancy outcomes. GBS colonization is also transient in nature, which likely reflects the contributions of pathogen determinants, interactions with commensal flora, and host factors, making this environment particularly challenging to understand. Additionally, dietary zinc deficiency is a health concern on the global scale that is known to be associated with recurrent bacterial infection and increased rate of preterm birth or stillbirth. However, the impact of zinc deficiency on vaginal health has not yet been studied. Here we use a murine model to assess the role of dietary zinc on GBS burden and the impact of GBS colonization on the vaginal microbiome. We show that GBS vaginal colonization is increased in a zinc-deficient host and that the presence of GBS significantly alters the microbial community structure of the vagina. Using machine learning approaches, we show that vaginal community turnover during GBS colonization is driven by computationally predictable changes in key taxa, including several organisms not previously described in the context of the vaginal microbiota, such as Akkermansia muciniphila. We observed that A. muciniphila increases GBS vaginal persistence and, in a cohort of human vaginal microbiome samples collected throughout pregnancy, we observed an increased prevalence of codetection of GBS and A. muciniphila in patients who delivered preterm compared to those who delivered at full term. These findings reveal the importance and complexity of both host zinc availability and native microbiome to GBS vaginal persistence. IMPORTANCE The presence of group B Streptococcus (GBS) in the vaginal tract, perturbations in the vaginal microbiota, and dietary zinc deficiency are three factors that are independently known to be associated with increased risk of adverse pregnancy outcomes. Here, we developed an experimental mouse model to assess the impact of dietary zinc deficiency on GBS vaginal burden and persistence and to determine how changes in GBS colonization impact vaginal microbial structure. We have employed unique animal, in silica metabolic, and machine learning models, paired with analyses of human cohort data, to identify taxonomic biomarkers that contribute to host susceptibility to GBS vaginal persistence. Collectively, the data reported here identify that both dietary zinc deficiency and the presence of A. muciniphila could perpetuate an increased GBS burden and prolonged exposure in the vaginal tract, which potentiate the risk of invasive infection in utero and in the newborn.

Heavy Metals Contaminants in Watercress (Nasturtium officinale R. BR.): Toxicity and Risk Assessment for Humans along the Swat River Basin, Khyber Pakhtunkhwa, Pakistan

This research aimed to investigate the bioaccumulation and health risk associated with absorption of the selected heavy metals (HMs) i.e., lead (Pb), cadmium (Cd), zinc (Zn), and copper (Cu) in a wild leafy vegetable Nasturtium officinale that grows along the Swat River in swampy areas. The areas were categorized using the ecological risk index (RI), which indicates how heavy metal concentrations in soil and plants change over time. The bioaccumulation factor was greater than that at the 400 ≤ RI sites, indicating a probable health risk of these metals from N. officinale consumption. Furthermore, the health risk index for Cd and Pb was more significant, i.e., greater than one in the majority of the samples, indicating health concerns associated with consuming N. officinale from the study site. However, Zn and Cu levels were lower than the nutritionally needed levels, raising the risk of deficiency in the population. Plants cultivated in Pb and Cd-polluted sites were nutrient deficient in Cu and Zn. Intake of such plants can expose people to HM contamination and nutritional deficiencies. The results concluded that the plants accumulated significant HM contents and may have health concerns but are safe for consumption in children and adults.

Zinc homeostasis in immunity and its association with preterm births

Preterm birth is among the most common adverse pregnancy outcomes and is the leading cause of neonatal mortality and morbidity. While trace elements are essential for humans, their specific roles in the prenatal period remain unexplored. Zinc, a ubiquitous element plays a pivotal role in protein synthesis, cell division, nucleic acid metabolism, apoptosis, ageing, reproduction, immunological as well as antioxidant defense mechanism. Although zinc quantities are very small in body tissue, it is involved in every conceivable biochemical pathway which is critical for the performance of various functions necessary to sustain life. Owing to the multifactorial role of zinc, it is not possible to attribute a certain zinc dependent mechanism in pre-term births. Although the effect of zinc deficiency on immunity, its impact on maternal function and health as well as its role in the developing foetus is well documented, much less attention has been given to the understanding of micronutrient zinc homeostasis in immunity and its association with preterm births. Despite extensive research, the pathway by which zinc regulates pregnancy outcomes as well as the function of immune cells in controlling the delivery status (term/ preterm) is still obscure. The present review aims to focus on the understanding of relationship of micronutrient zinc homeostasis in immunity and its association with preterm births.

Maternal Serum Zinc Level and Pre-eclampsia Risk in African Women: a Systematic Review and Meta-analysis

Some studies have reported the association between maternal serum zinc (Zn) levels and pre-eclampsia. However, many studies have reported controversial results. Hence, this systematic review and meta-analysis was planned to generate summarized evidence on the association between maternal serum Zn levels and pre-eclampsia in African women. Four electronic databases such as PubMed, Hinari, Google Scholar, and African Journals Online were searched for studies published in English. Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument, and Newcastle-Ottawa Scale were used for data extraction and quality assessment of the included studies. The meta-regression analysis was performed by the Stata 14 software. The standardized mean difference (SMD) values of lipid profiles were computed to assess their association with pre-eclampsia at 95% CI. A total of 12 observational studies were included. The mean values of serum Zn level were significantly lower in pre-eclamptic women as compared with normotensive pregnant women (Zn = 59.40 ± 22.80 μg/dL and 80.24 ± 16.04 μg/dL), respectively. The pooled SMD of Zn was significantly reduced in pre-eclamptic women as compared with normotensive pregnant women with the SMD of -1.45 (95% CI -2.26, -0.65) at 95% CI. In this review, we found that the maternal Zn serum level was significantly reduced in pre-eclamptic women than normotensive pregnant women. This suggests that Zn could be involved in the etio-pathogenesis of pre-eclampsia. However, the specific functions of Zn in pre-eclampsia pathogenesis should be proved in large-scale clinical trial studies.

Performance of urine, blood, and integrated metal biomarkers in relation to birth outcomes in a mixture setting

BACKGROUND

Studies on the health effects of metal mixtures typically utilize biomarkers measured in a single biological medium, such as blood or urine. However, the ability to evaluate mixture effects are limited by the uncertainty whether a unified medium can fully capture exposure for each metal. Therefore, it is important to compare and assess metal mixtures measured in different media in epidemiology studies.

OBJECTIVES

The aim of this study was to examine the mixture predictive performance of urine and blood metal biomarkers and integrated multi-media biomarkers in association with birth outcomes.

METHODS

In our analysis of 847 women from the Puerto Rico PROTECT Cohort, we measured 10 essential and non-essential metals in repeated and paired samples of urine and blood during pregnancy. For each metal, we integrated exposure estimates from paired urine and blood biomarkers into multi-media biomarkers (MMBs), using intraclass-correlation coefficient (ICC) and weighted quantile sum (WQS) approaches. Using Ridge regressions, four separate Environmental risk scores (ERSs) for metals in urine, blood, MMBICC, and MMBWQS were computed as a weighted sum of the 10 metal concentrations. We then examined associations between urine, blood, and multi-media biomarker ERSs and birth outcomes using linear and logistic regressions, adjusting for maternal age, maternal education, pre-pregnancy body mass index (BMI), and second-hand smoke exposure. The performance of each ERS was evaluated with continuous and tertile estimates and 95% confidence intervals of the odds ratio of preterm birth using area under the curve (AUC).

RESULTS

Pb was the most important contributor of blood ERS as well as the two integrated multi-media biomarker ERSs. Individuals with high ERS (3rd tertile) showed increased odds of preterm birth compared to individuals with low ERS (1st tertile), with 2.8-fold (95% CI, 1.49 to 5.40) for urine (specific gravity corrected); 3.2- fold (95% CI, 1.68 to 6.25) for blood; 3.9-fold (95% CI, 1.72 to 8.66) for multi-media biomarkers composed using ICC; and 5.2-fold (95% CI, 2.34 to 11.42) for multi-media biomarkers composed using WQS. The four ERSs had comparable predictive performances (AUC ranging from 0.64 to 0.68) when urine is examined with specific gravity corrected concentrations.

CONCLUSIONS

Within a practical metal panel, measuring metals in either urine or blood may be an equally good approach to evaluate the metals as a mixture. Applications in practical study design require validation of these methods with other cohorts, larger panels of metals and within the context of other adverse health effects of interest.

Effect of maternal zinc supplementation or zinc status on pregnancy complications and perinatal outcomes: An umbrella review of meta-analyses

Zinc is an essential trace element involved in different physiological functions. During pregnancy, it plays a crucial role in healthy embryogenesis. This umbrella review, therefore, aimed to summarize the existing literature of meta-analyses evaluating the effect of maternal zinc supplementation or zinc status on maternal and neonatal outcomes. Two databases, PubMed and Scopus, were selected to search the available literature without any temporal restriction. The literature search was performed during October 2020 and a total of 192 records were identified through the literature search. After screening the titles and applying the inclusion/exclusion criteria, finally, 15 articles were included in this umbrella review. This umbrella review showed that maternal zinc supplements reduce the risk of preterm birth. Although no substantial effect of zinc supplements was found for other feto-maternal outcomes. Also, we found a significant relationship between low maternal zinc status and risk of pregnancy complications. Zinc supplements reduce the risk of preterm birth. Long-term interventions and cohort studies are needed for future research directions. Further studies and a thorough investigation will help to decide the recommended zinc dose or intake during pregnancy.

Effects of vitamin and mineral supplementation during pregnancy on maternal, birth, child health and development outcomes in low- and middle-income countries: A systematic review

Background

Almost two billion people who are deficient in vitamins and minerals are women and children in low- and middle-income countries (LMIC). These deficiencies are worsened during pregnancy due to increased energy and nutritional demands, causing adverse outcomes in mother and child. To reduce micronutrient deficiencies, several strategies have been implemented, including diet diversification, large-scale and targeted fortification, staple crop bio-fortification and micronutrient supplementation.

Objectives

To evaluate and summarize the available evidence on the effects of micronutrient supplementation during pregnancy in LMIC on maternal, fetal, child health and child development outcomes. This review will assess the impact of single micronutrient supplementation (calcium, vitamin A, iron, vitamin D, iodine, zinc, vitamin B12), iron-folic acid (IFA) supplementation, multiple micronutrient (MMN) supplementation, and lipid-based nutrient supplementation (LNS) during pregnancy.

Search Methods

We searched papers published from 1995 to 31 October 2019 (related programmes and good quality studies pre-1995 were limited) in CAB Abstracts, CINAHL, Cochrane Central Register of Controlled Trials, Embase, International Initiative for Impact Evaluations, LILACS, Medline, POPLINE, Web of Science, WHOLIS, ProQuest Dissertations & Theses Global, R4D, WHO International Clinical Trials Registry Platform. Non-indexed grey literature searches were conducted using Google, Google Scholar, and web pages of key international nutrition agencies.

Selection Criteria

We included randomized controlled trials (individual and cluster-randomized) and quasi-experimental studies that evaluated micronutrient supplementation in healthy, pregnant women of any age and parity living in a LMIC. LMIC were defined by the World Bank Group at the time of the search for this review. While the aim was to include healthy pregnant women, it is likely that these populations had one or more micronutrient deficiencies at baseline; women were not excluded on this basis.

Data Collection and Analysis

Two authors independently assessed studies for inclusion and risk of bias, and conducted data extraction. Data were matched to check for accuracy. Quality of evidence was assessed using the GRADE approach.

Main Results

A total of 314 papers across 72 studies (451,723 women) were eligible for inclusion, of which 64 studies (439,649 women) contributed to meta-analyses. Seven studies assessed iron-folic acid (IFA) supplementation versus folic acid; 34 studies assessed MMN vs. IFA; 4 studies assessed LNS vs. MMN; 13 evaluated iron; 13 assessed zinc; 9 evaluated vitamin A; 11 assessed vitamin D; and 6 assessed calcium. Several studies were eligible for inclusion in multiple types of supplementation. IFA compared to folic acid showed a large and significant (48%) reduction in the risk of maternal anaemia (average risk ratio (RR) 0.52, 95% CI 0.41 to 0.66; studies = 5; participants = 15,540; moderate-quality evidence). As well, IFA supplementation demonstrated a smaller but significant, 12% reduction in risk of low birthweight (LBW) babies (average RR 0.88, 95% CI 0.78 to 0.99; studies = 4; participants = 17,257; high-quality evidence). MMN supplementation was defined as any supplement that contained at least 3 micronutrients. Post-hoc analyses were conducted, where possible, comparing the differences in effect of MMN with 4+ components and MMN with 3 or 4 components. When compared to iron with or without FA, MMN supplementation reduced the risk of LBW by 15% (average RR 0.85, 95% CI 0.77 to 0.93; studies = 28; participants = 79,972); this effect was greater in MMN with >4 micronutrients (average RR 0.79, 95% CI 0.71 to 0.88; studies = 19; participants = 68,138 versus average RR 1.01, 95% CI 0.92 to 1.11; studies = 9; participants = 11,834). There was a small and significant reduction in the risk of stillbirths (average RR 0.91; 95% CI 0.86 to 0.98; studies = 22; participants = 96,772) and a small and significant effect on the risk of small-for-gestational age (SGA) (average RR 0.93; 95% CI 0.88 to 0.98; studies = 19; participants = 52,965). For stillbirths and SGA, the effects were greater among those provided MMN with 4+ micronutrients. Children whose mothers had been supplemented with MMN, compared to IFA, demonstrated a 16% reduced risk of diarrhea (average RR 0.84; 95% CI 0.76 to 0.92; studies = 4; participants = 3,142). LNS supplementation, compared to MMN, made no difference to any outcome; however, the evidence is limited. Iron supplementation, when compared to no iron or placebo, showed a large and significant effect on maternal anaemia, a reduction of 47% (average RR 0.53, 95% CI 0.43 to 0.65; studies = 6; participants = 15,737; moderate-quality evidence) and a small and significant effect on LBW (average RR 0.88, 95% CI 0.78 to 0.99; studies = 4; participants = 17,257; high-quality evidence). Zinc and vitamin A supplementation, each both compared to placebo, had no impact on any outcome examined with the exception of potentially improving serum/plasma zinc (mean difference (MD) 0.43 umol/L; 95% CI -0.04 to 0.89; studies = 5; participants = 1,202) and serum/plasma retinol (MD 0.13 umol/L; 95% CI -0.03 to 0.30; studies = 6; participants = 1,654), respectively. When compared to placebo, vitamin D supplementation may have reduced the risk of preterm births (average RR 0.64; 95% CI 0.40 to 1.04; studies = 7; participants = 1,262), though the upper CI just crosses the line of no effect. Similarly, calcium supplementation versus placebo may have improved rates of pre-eclampsia/eclampsia (average RR 0.45; 95% CI 0.19 to 1.06; studies = 4; participants = 9,616), though the upper CI just crosses 1.

Authors' Conclusions

The findings suggest that MMN and vitamin supplementation improve maternal and child health outcomes, including maternal anaemia, LBW, preterm birth, SGA, stillbirths, micronutrient deficiencies, and morbidities, including pre-eclampsia/eclampsia and diarrhea among children. MMN supplementation demonstrated a beneficial impact on the most number of outcomes. In addition, MMN with >4 micronutrients appeared to be more impactful than MMN with only 3 or 4 micronutrients included in the tablet. Very few studies conducted longitudinal analysis on longer-term health outcomes for the child, such as anthropometric measures and developmental outcomes; this may be an important area for future research. This review may provide some basis to guide continual discourse around replacing IFA supplementation with MMN along with the use of single micronutrient supplementation programs for specific outcomes.

Effect of maternal zinc deficiency on offspring health: The epigenetic impact

BACKGROUND

Zinc deficiency is associated with adverse effects on maternal health and pregnancy outcomes. These consequences have been reported over the years from zinc supplementation trials and observational studies whereby outcomes of maternal, foetal and infant health were measured. Owing to the importance of zinc in the functions of epigenetic enzymes, pre-clinical studies have shown that its deficiency could disrupt biological activities that involve epigenetic mechanisms in offspring. Thus, this review assessed the link between epigenetics and the effects of maternal zinc deficiency on the offspring's health in animal studies.

METHODS

Research articles were retrieved without date restriction from PubMed, Web of Science, ScienceDirect, and Google Scholar databases, as well as reference lists of relevant articles. The search terms used were "zinc deficiency", "maternal zinc deficiency", "epigenetics", and "offspring." Six studies met the eligibility criteria and were reviewed.

RESULTS

All the eligible studies reported maternal zinc deficiency and observed changes in epigenetic markers on the progeny during prenatal and postnatal stages of development. The main epigenetic markers reported were global and gene specific methylation and/ or acetylation. The epigenetic changes led to mortality, disruption in development, and risk of later life diseases.

CONCLUSION

Maternal zinc deficiency is associated with epigenetic modifications in offspring, which induce pathologies and increase the risk of later life diseases. More research and insight into the epigenetic mechanisms could spring up new approaches to combat the associated disease conditions.

Zinc Oxide Exerts Anti-Inflammatory Properties on Human Placental Cells

Background: An aberrant and persistent inflammatory state at the fetal-maternal interface is considered as a key contributor in compromised pregnancies. Decidual endothelial cells (DECs) play a pivotal role in the control of the local decidual inflammation. The aim of the current study was to determine whether dietary supplement with zinc oxide (ZnO), due to its very low adverse effects, may be useful for modulating the inflammatory response in the first trimester of pregnancy. Methods: The anti-inflammatory properties of ZnO in pregnancy were evaluated by in vitro tests on endothelial cells isolated from normal deciduas and on a trophoblast cell line (HTR8/Svneo). The effects of this treatment were analyzed in terms of adhesion molecule expression and inflammatory cytokine secretion, by real time-quantitative PCR (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). Results: Our data showed that ZnO was able to reduce the inflammatory response of DECs, in terms of vascular cell adhesion molecule-1 (VCAM-1), interleukin (IL)-8, IL-6, tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein-1 (MCP-1) expression induced by TNF-α stimulation. This compound exerted no effect on intracellular adhesion molecule-1 (ICAM-1) exocytosis induced by TNF-α on stimulated trophoblast cells, but significantly reduced their IL-6 expression. Conclusion: According to these results, it can be suggested that the ZnO supplement, through its modulation of the pro-inflammatory response of DECs, can be used in pregnancy for the prevention of local decidual inflammation.

Maternal blood metal and metalloid concentrations in association with birth outcomes in Northern Puerto Rico

BACKGROUND

In previous studies, exposures to heavy metals such as Pb and Cd have been associated with adverse birth outcomes; however, knowledge on effects at low levels of exposure and of other elements remain limited.

METHOD

We examined individual and mixture effects of metals and metalloids on birth outcomes among 812 pregnant women in the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) cohort. We measured 16 essential and non-essential metal(loid)s in maternal blood collected at 16-20 and 24-28 weeks gestation. We used linear and logistic regression to independently examine associations between geometric mean (GM) concentrations of each metal across visits and gestational age, birthweight z-scores, preterm birth, small for gestational age (SGA), and large for gestational age (LGA). We evaluated effect modification with infant sex*metal interaction terms. To identify critical windows of susceptibility, birth outcomes were regressed on visit-specific metal concentrations. Furthermore, average metal concentrations were divided into tertiles to examine the potential for non-linear relationships. We used elastic net (ENET) regularization to construct Environmental Risk Score (ERS) as a metal risk score and Bayesian Kernel Machine Regression (BKMR) to identify individual metals most critical to each outcome, accounting for correlated exposures.

RESULTS

In adjusted models, an interquartile range (IQR) increase in GM lead (Pb) was associated with 1.63 higher odds of preterm birth (95%CI = 1.17, 2.28) and 2 days shorter gestational age (95% CI = -3.1, -0.5). Manganese (Mn) and zinc (Zn) were also associated with higher odds of preterm birth and shorter gestational age; the associations were strongest among the highest tertile for Mn and among females for Zn. Mercury (Hg) was associated with higher risk of preterm birth at the later window of pregnancy. Ni measured later in pregnancy was associated with lower odds of SGA. ENET and BKMR models selected similar metals as "important" predictors of birth outcomes. The association between ERS and preterm birth was assessed and the third tertile of ERS was significantly associated with an elevated odds ratio of 2.13 (95% CI = 1.12, 5.49) for preterm birth compared to the first tertile.

CONCLUSION

As the PROTECT cohort has lower Pb concentrations (GM = 0.33 μg/dL) compared to the mainland US, our findings suggest that low-level prenatal lead exposure, as well as elevated Mn and Zn exposure, may adversely affect birth outcomes. Improved understanding on environmental factors contributing to preterm birth, together with sustainable technologies to remove contamination, will have a direct impact in Puerto Rico and elsewhere.

Efficacy of high zinc biofortified wheat in improvement of micronutrient status, and prevention of morbidity among preschool children and women - a double masked, randomized, controlled trial

Background

Biofortification of staple food crops with zinc (Zn) can be one of the cost-effective and sustainable strategies to combat zinc deficiency and prevent morbidity among the target population. Agronomic approaches such as application of Zn fertilizers to soil and/or foliar spray seem to be a practical tool for Zn biofortification of wheat. However, there is a need to evaluate its efficacy from randomized controlled trials. This study aimed to evaluate the efficacy of zinc biofortified wheat flour on zinc status and its impact on morbidity among children aged 4–6 years and non-pregnant non lactating woman of child bearing age (WCBA) in Delhi, India.

Methods

In a community based, double-masked randomized controlled trial, 6005 participants (WCBA and child pairs) were enrolled and randomly allocated to receive either high zinc biofortified wheat flour (HZn, 30 ppm zinc daily) or low zinc biofortified wheat flour (LZn, 20 ppm zinc daily) for 6 months (WCBA @ 360 g/day and children @ 120 g/day). Baseline and endline blood samples were obtained for assessing hematological markers; zinc status and data on compliance and morbidity were collected.

Results

Compliance rates were high; ~ 88% of the WCBAs in both the groups consumed 50% or more of recommended amount of biofortfied wheat flour during the follow up. Similarly 86.9% children in HZn and 87.5% in LZn consumed 50% or more of recommended wheat flour intake. There was no significant difference in mean zinc levels between the groups at end study. This observation might be due to a marginal difference in zinc content (10 ppm) between the HZn and LZn wheat flour, and a short intervention period. However a positive impact of bio-fortification on self-reported morbidity was observed. Compared to children in LZn group, children in HZn group had 17% (95% CI: 6 to 31%, p = 0.05) and 40% (95% CI: 16 to 57%; p = 0.0019) reduction in days with pneumonia and vomiting respectively. WCBA in the HZn group also showed a statistically significant 9% fewer days with fever compared to LZn group.

Conclusions

Biofortified wheat flour had a good compliance among children and WCBAs. Significant improvement on some of the self-reported morbidity indicators suggests that evaluating longer-term effects of biofortification with higher grain zinc content would be more appropriate.

Trial registration

http://ctri.nic.in/Clinicaltrials/, CTRI/2014/04/004527, Registered April 7, 2014.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0391-5) contains supplementary material, which is available to authorized users.

Factors Affecting the FcRn-Mediated Transplacental Transfer of Antibodies and Implications for Vaccination in Pregnancy

At birth, neonates are particularly vulnerable to infection and transplacental transfer of immunoglobulin G (IgG) from mother to fetus provides crucial protection in the first weeks of life. Transcytosis of IgG occurs via binding with the neonatal Fc receptor (FcRn) in the placental synctiotrophoblast. As maternal vaccination becomes an increasingly important strategy for the protection of young infants, improving our understanding of transplacental transfer and the factors that may affect this will become increasingly important, especially in low-income countries where the burden of morbidity and mortality is highest. This review highlights factors of relevance to maternal vaccination that may modulate placental transfer—IgG subclass, glycosylation of antibody, total maternal IgG concentration, maternal disease, infant gestational age, and birthweight—and outlines the conflicting evidence and questions that remain regarding the complexities of these relationships. Furthermore, the intricacies of the Ab–FcRn interaction remain poorly understood and models that may help address future research questions are described.

Nutrition (Micronutrients) in Child Growth and Development: A Systematic Review on Current Evidence, Recommendations and Opportunities for Further Research

OBJECTIVE

An important aspect of malnutrition is deficiency of different micronutrients during pregnancy or early childhood. We systematically reviewed the role of nutrition in child growth (weight or height gain) and development.

METHODS

A comprehensive literature search was done on PubMed/Cochrane Library browsing through 38,795 abstracts until December 31, 2016 to select systematic reviews/meta-analyses and individual randomized controlled trials (RCTs) of micronutrient supplementation.

RESULTS

Micronutrients studied included iron, iodine, folate, zinc, calcium, magnesium, selenium, vitamin D, vitamin A, vitamin B complex, and multiple micronutrients. We summarize evidence with details and results of RCTs, highlight strengths/weaknesses, and critically interpret findings. Effects of breastfeeding-promotion, food-supplementation (complementary and school feeding), conditional-cash-transfers, and integrated nutrition/psychosocial interventions are discussed.

CONCLUSION

Based on this evidence we make policy and programmatic recommendations for supplementation to mothers and children at high-risk of deficiency.

Upregulation of Zinc Absorption Matches Increases in Physiologic Requirements for Zinc in Women Consuming High- or Moderate-Phytate Diets during Late Pregnancy and Early Lactation

Background: Estimated physiologic requirements (PRs) for zinc increase in late pregnancy and early lactation, but the effect on dietary zinc requirements is uncertain.Objective: The aim of this study was to determine changes in daily fractional absorbed zinc and total absorbed zinc (TAZ) from ad libitum diets of differing phytate contents in relation to physiologic zinc requirements during pregnancy and lactation.Methods: This was a prospective observational study of zinc absorption at 8 (phase 1) and 34 (phase 2) wk of gestation and 2 (phase 3) and 6 (phase 4) mo of lactation. Participants were indigenous Guatemalan women of childbearing age whose major food staple was maize and who had been randomly assigned in a larger study to either of 2 ad libitum feeding groups: low-phytate maize (LP; 1.6 mg/g; n = 14) or control maize (C; 7.1 mg/g; n = 8). Total dietary zinc (milligrams per day, TDZ) and phytate (milligrams per day) were determined from duplicate diets and fractional absorption (FAZ) by dual isotope ratio technique (TAZ = TDZ × FAZ). All variables were examined longitudinally and by group and compared with PRs. TAZ values at later phases were compared with phase 1. Measured TAZ was compared with predicted TAZ for nonpregnant, nonlactating (NPNL) women.Results: TAZ was greater in the LP group than in the C group at all phases. All variables increased from phase 1 to phases 2 and 3 and declined at phase 4. TAZ increased by 1.25 mg/d (P = 0.045) in the C group and by 0.81 mg/d (P = 0.058) in the LP group at phase 2. At phase 3, the increases were 2.66 mg/d (P = 0.002) in the C group and 2.28 mg/d (P = 0.0004) in the LP group, compared with a 1.37-mg/d increase in PR. Measured TAZ was greater than predicted values in phases 2-4.Conclusions: Upregulation of zinc absorption in late pregnancy and early lactation matches increases in PRs of pregnant and lactating women, regardless of dietary phytate, which has implications for dietary zinc requirements of pregnant and lactating women.

Magnitude of Zinc Deficiency among Nulliparous Nonpregnant Women in a Rural Community of Haryana State, India

Zinc deficiency during pregnancy affects the outcome of pregnancy. A high prevalence of zinc deficiency (55.5%) has been reported among pregnant women. It is not known whether pregnancy leads to zinc deficiency due to the increased fetal needs or whether the women are zinc deficient when they become pregnant. No data are available on the zinc status of nulliparous nonpregnant women from India. To assess the magnitude of zinc deficiency among nulliparous nonpregnant women in a rural community of Haryana State, India. A community-based cross-sectional survey was conducted in six villages of a rural area in a district of Haryana State, India. All nulliparous nonpregnant women aged 18 years or over who were willing to participate in the study were enrolled. Each woman was questioned about her age, socioeconomic status, and dietary pattern with the use of a pretested semistructured questionnaire. Blood from the antecubital vein was drawn to assess the serum zinc levels using an atomic absorption spectrophotometer. Serum zinc levels less than 70.0 μg/dl were considered to indicate zinc deficiency. The dietary intakes of zinc, protein, and calories were assessed by the 24-hour dietary recall method. Two hundred eighty-eight nulliparous nonpregnant women were enrolled. Forty-one percent had zinc deficiency, and 75.7%, 1.4%, and 7.3% of the women consumed less than 50% of the recommended intake of zinc, protein, and calories, respectively. Women who consumed less than 50% of the recommended intake of calories (1,875 kcal) were at a 4.9 times higher risk of zinc deficiency than women who consumed more than 50% of the recommended intake. A high prevalence of zinc deficiency was found among the nulliparous nonpregnant women in the area studied.

Semiparametric Multinomial Ordinal Model to Analyze Spatial Patterns of Child Birth Weight in Nigeria

Background: Birth weight is an important health parameter for obstetricians and gynaecologists. It is a good health indicator of a child-bearing mother and a strong predictor of infant morbidity and mortality. Methods: This paper utilizes data on 28,647 children born between 2003–2008 obtained from the 2008 Nigeria Demographic and Health Survey (NDHS). For a simple epidemiological convenience, the occurrence of a newborn weight can intuitively be considered to be categorical in nature and the thresholds can be put on a continuous scale. In survey reporting, the mothers frequently estimate their infant’s birth weight and make a classification in ordinal category (low, normal, large) instead of actual birth weight. The study fits a multinomial regression model to analyze the relationships between the polytomous response and different kind of covariates in a unified manner. We estimate the fixed effects of bio-social covariates parametrically and the non-linear effect modeled using P-spline. The spatial component was modeled using conditional autoregressive error. A penalized maximum likelihood estimation was performed to estimate the model parameters. Results: We found risk factors that are positively associated with low birth weight, which include multiple birth, short birth interval, death of sibling, childhood diarrhea, fever, mother’s smoking, firewood/dung cooking and poor household. Results further showed that iron syrup supplementation, antenatal attendance, mother literacy and household wealth had significant association with low probability of low birth weight. The finding also showed spatial patterns, which are not captured by the underlying determinants, and we produced probability predictive maps of the spatial residual effects. Conclusions: In addition to the statistical relevance of our method, the generated spatial maps identify highly endemic areas of low birth weight that can assist government agency to channel scarce health resources. A comprehensive approach which institutes a combination of interventions to improve the overall health care of the women is needed.

Mineral essential elements for nutrition in different chocolate products

In this work, the essential mineral nutritional elements in cocoa beans, in chocolates at different cocoa percentage (60,70,80 and 90%) and in milk chocolate are evaluated. Dark chocolates are confirmed as an excellent source of magnesium (252.2 mg/100 g) and iron (10.9 mg/100 g): in chocolate containing 90% cocoa, their content corresponds to, respectively, 67.0% and 80.3 of Nutrient Reference Values (NRV) in the European Union. The chocolate containing 90% cocoa is also a good source of zinc (3.5 mg/100 g), which is important for the immune system, and selenium (0.1 mg/100 g). Three main components suitable to explain the mineral concentrations are analyzed by factor analysis. The component 1 can be interpreted as the contribution from the cocoa beans, owing to the mineral characteristics of the soil in which they have grown; the component 2 is mainly due to the manipulation and transformation of the cocoa in chocolate, while the component 3 represents the milk powder.

Studies on physicochemical and nutritional properties of aerial parts of Cassia occidentalis L

In the present, work chemical composition and nutritional value of aerial parts of Cassia occidentalis L. was studied. The aerial parts of C. occidentalis possess favorable physicochemical properties with good nutritional value, such as high energy value, crude fibers, and vitamin levels. The X-ray fluorescence spectrophotometry data revealed that the sample is rich in minerals, especially in Fe, Ca, K, and Mn. Further, minerals such as Mg, Zn, Cu, Na, P, and S are present in good amount and depicted the nutritional value of the selected material. The plant sample is rich in phytochemicals such as flavonoids, alkaloids, lignin, tannins, and phenols. The presence of phytochemical constituents was confirmed by gas chromatography–mass spectrometry profile and high-performance thin layer chromatography fingerprinting techniques. The findings stimulate the on-farm cultivation of C. occidentalis on a large scale to relieve the iron deficiency in local community, and it can be used as a dietary supplement to treat anemia.

Vitamin A, vitamin E, iron and zinc status in a cohort of HIV-infected mothers and their uninfected infants

Introduction: We hypothesized that nutritional deficiency would be common in a cohort of postpartum, human immunodeficiency virus (HIV)-infected women and their infants.

METHODS

Weight and height, as well as blood concentrations of retinol, α-tocopherol, ferritin, hemoglobin, and zinc, were measured in mothers after delivery and in their infants at birth and at 6-12 weeks and six months of age. Retinol and α-tocopherol levels were quantified by high performance liquid chromatography, and zinc levels were measured by atomic absorption spectrophotometry. The maternal body mass index during pregnancy was adjusted for gestational age (adjBMI).

RESULTS

Among the 97 women 19.6% were underweight. Laboratory abnormalities were most frequently observed for the hemoglobin (46.4%), zinc (41.1%), retinol (12.5%) and ferritin (6.5%) levels. Five percent of the women had mean corpuscular hemoglobin concentrations < 31g/dL. The most common deficiency in the infants was α-tocopherol (81%) at birth; however, only 18.5% of infants had deficient levels at six months of age. Large percentages of infants had zinc (36.8%) and retinol (29.5%) deficiencies at birth; however, these percentages decreased to 17.5% and 18.5%, respectively, by six months of age. No associations between infant micronutrient deficiencies and either the maternal adjBMI category or maternal micronutrient deficiencies were found.

CONCLUSIONS

Micronutrient deficiencies were common in HIV-infected women and their infants. Micronutrient deficiencies were less prevalent in the infants at six months of age. Neither underweight women nor their infants at birth were at increased risk for micronutrient deficiencies.

Copper, magnesium, zinc and calcium status in osteopenic and osteoporotic post-menopausal women

Copper, magnesium, zinc and calcium status were measured in postmenopausal women with osteoporosis (n = 23) and osteopenia (n = 28) as classified on the basis of the T-score of the femur neck and dual energy X-ray absorptiometry results. Anthropometric indices, dietary intake and serum copper, magnesium, zinc and calcium were assessed. The results of our study showed that the mean dietary intake of magnesium, zinc and calcium in post-menopausal women with low bone density were significantly lower than recommended dietary allowance. The mean serum levels of zinc (P = 0.001) and copper (P = 0.000) were significantly lower than normal range and 40.4% of this participants had serum magnesium levels lower than normal range. No statistically significant differences were observed between the osteopenic and osteoporotic groups with respect to serum levels and dietary intakes of copper, calcium, magnesium and zinc. Due to the mineral deficiency in post-menopausal women with low bone density and the key role of minerals on bone health, supplementation with magnesium, calcium, zinc and perhaps copper recommended.

Zinc supplementation for improving pregnancy and infant outcome

BACKGROUND

It has been suggested that low serum zinc levels may be associated with suboptimal outcomes of pregnancy such as prolonged labour, atonic postpartum haemorrhage, pregnancy-induced hypertension, preterm labour and post-term pregnancies, although many of these associations have not yet been established.

OBJECTIVES

To assess the effects of zinc supplementation in pregnancy on maternal, fetal, neonatal and infant outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 October 2014) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised trials of zinc supplementation in pregnancy. We excluded quasi-randomised controlled trials.

DATA COLLECTION AND ANALYSIS

Three review authors applied the study selection criteria, assessed trial quality and extracted data. When necessary, we contacted study authors for additional information. The quality of the evidence was assessed using GRADE.

MAIN RESULTS

We included 21 randomised controlled trials (RCTs) reported in 54 papers involving over 17,000 women and their babies. One trial did not contribute data. Trials were generally at low risk of bias. Zinc supplementation resulted in a small reduction in preterm birth (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.76 to 0.97 in 16 RCTs; 16 trials of 7637 women). This was not accompanied by a similar reduction in numbers of babies with low birthweight (RR 0.93, 95% CI 0.78 to 1.12; 14 trials of 5643 women). No clear differences were seen between the zinc and no zinc groups for any of the other primary maternal or neonatal outcomes, except for induction of labour in a single trial. No differing patterns were evident in the subgroups of women with low versus normal zinc and nutrition levels or in women who complied with their treatment versus those who did not. The GRADE quality of the evidence was moderate for preterm birth, small-for-gestational age, and low birthweight, and low for stillbirth or neonatal death and birthweight.

AUTHORS' CONCLUSIONS

The evidence for a 14% relative reduction in preterm birth for zinc compared with placebo was primarily represented by trials involving women of low income and this has some relevance in areas of high perinatal mortality. There was no convincing evidence that zinc supplementation during pregnancy results in other useful and important benefits. Since the preterm association could well reflect poor nutrition, studies to address ways of improving the overall nutritional status of populations in impoverished areas, rather than focusing on micronutrient and or zinc supplementation in isolation, should be an urgent priority.

The effect of zinc supplementation of lactating rats on short-term and long-term memory of their male offspring

BACKGROUND

In this study the effect of zinc chloride (ZnCl2) administration on the short-term and long-term memory of rats were assessed.

METHODS

We enrolled six groups of adult female and control group of eight Wistar rats in each group. One group was control group with free access to food and water, and five groups drunk zinc chloride in different doses (20, 30, 50, 70 and 100 mg/kg/day) in drinking water for two weeks during lactation .One month after birth, a shuttle box used to short- term and long-term memory and the latency in entering the dark chamber as well.

RESULTS

This experiment showed that maternal 70 mg/kg dietary zinc during lactation influenced the working memory of rats' offspring in all groups. Rats received 100 mg/kg/day zinc during lactation so they had significant impairment in working memory (short-term) of their offspring (P<0.05). There was no significant difference in reference (long-term) memory of all groups.

CONCLUSION

Drug consumption below70 mg/kg/day zinc chloride during lactation had no effect. While enhanced 100 mg/ kg/ day zinc in lactating rats could cause short-term memory impairment.

Zinc supplementation for improving pregnancy and infant outcome

BACKGROUND

It has been suggested that low serum zinc levels may be associated with suboptimal outcomes of pregnancy such as prolonged labour, atonic postpartum haemorrhage, pregnancy-induced hypertension, preterm labour and post-term pregnancies, although many of these associations have not yet been established.

OBJECTIVES

To assess the effects of zinc supplementation in pregnancy on maternal, fetal, neonatal and infant outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2011) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised trials of zinc supplementation in pregnancy. We excluded quasi-randomised controlled trials.

DATA COLLECTION AND ANALYSIS

Three review authors applied the study selection criteria, assessed trial quality and extracted data. When necessary, we contacted study authors for additional information.

MAIN RESULTS

We included 20 randomised controlled trials (RCTs) reported in 51 papers involving over 15,000 women and their babies. Trials were generally at low risk of bias. Zinc supplementation resulted in a small but significant reduction in preterm birth (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.76 to 0.97 in 16 RCTs; 16 trials of 7637 women). This was not accompanied by a similar reduction in numbers of babies with low birthweight (RR 0.93, 95% CI 0.78 to 1.12; 14 trials of 5643 women). No significant differences were seen between the zinc and no zinc groups for any of the other primary maternal or neonatal outcomes, except for induction of labour in a single trial. No differing patterns were evident in the subgroups of women with low versus normal zinc and nutrition levels or in women who complied with their treatment versus those who did not.

AUTHORS' CONCLUSIONS

The evidence for a 14% relative reduction in preterm birth for zinc compared with placebo was primarily represented by trials involving women of low income and this has some relevance in areas of high perinatal mortality. There was no convincing evidence that zinc supplementation during pregnancy results in other useful and important benefits. Since the preterm association could well reflect poor nutrition, studies to address ways of improving the overall nutritional status of populations in impoverished areas, rather than focusing on micronutrient and or zinc supplementation in isolation, should be an urgent priority.

Maternal zinc intakes and homeostatic adjustments during pregnancy and lactation

Zinc plays critical roles during embryogenesis, fetal growth, and milk secretion, which increase the zinc need for pregnancy and lactation. Increased needs can be met by increasing the dietary zinc intake, along with making homeostatic adjustments in zinc utilization. Potential homeostatic adjustments include changes in circulating zinc, increased zinc absorption, decreased zinc losses, and changes in whole body zinc kinetics. Although severe zinc deficiency during pregnancy has devastating effects, systematic reviews and meta-analysis of the effect of maternal zinc supplementation on pregnancy outcomes have consistently shown a limited benefit. We hypothesize, therefore, that zinc homeostatic adjustments during pregnancy and lactation improve zinc utilization sufficiently to provide the increased zinc needs in these stages and, therefore, mitigate immediate detrimental effects due to a low zinc intake. The specific questions addressed are the following: How is zinc utilization altered during pregnancy and lactation? Are those homeostatic adjustments influenced by maternal zinc status, dietary zinc, or zinc supplementation? These questions are addressed by critically reviewing results from published human studies on zinc homeostasis during pregnancy and lactation carried out in different populations worldwide.

Role of Heme Oxygenase, Leptin, Coenzyme Q10 and Trace Elements in Pre-eclamptic Women

The objective of this study to evaluate heme oxygenase (COHb), leptin and coenzyme Q10 (CoQ10) in pre-eclamptic women. Also Zinc, copper, Iron, total iron binding capacity, Ferritin and uric acid were assessed. 120 female subjects were included in this study. They were divided into, 60 female with normal pregnancy attending the outpatient clinic, 60 pre-eclamptic patients were recruited from obstetrics and gynaecology department El-kasr El-Aini hospital. The results showed that in pre-eclampatic group, leptin level was significantly increased while COHb and CoQ10 was significantly decreased. It is concluded that hemeoxygenase, leptin and coenzyme CoQ10 can be considered as new markers for prediction of pre-eclampsia.

Nutritionally mediated programming of the developing immune system

A growing body of evidence highlights the importance of a mother's nutrition from preconception through lactation in programming the emerging organ systems and homeostatic pathways of her offspring. The developing immune system may be particularly vulnerable. Indeed, examples of nutrition-mediated immune programming can be found in the literature on intra-uterine growth retardation, maternal micronutrient deficiencies, and infant feeding. Current models of immune ontogeny depict a "layered" expansion of increasingly complex defenses, which may be permanently altered by maternal malnutrition. One programming mechanism involves activation of the maternal hypothalamic-pituitary-adrenal axis in response to nutritional stress. Fetal or neonatal exposure to elevated stress hormones is linked in animal studies to permanent changes in neuroendocrine-immune interactions, with diverse manifestations such as an attenuated inflammatory response or reduced resistance to tumor colonization. Maternal malnutrition may also have a direct influence, as evidenced by nutrient-driven epigenetic changes to developing T regulatory cells and subsequent risk of allergy or asthma. A 3rd programming pathway involves placental or breast milk transfer of maternal immune factors with immunomodulatory functions (e.g. cytokines). Maternal malnutrition can directly affect transfer mechanisms or influence the quality or quantity of transferred factors. The public health implications of nutrition-mediated immune programming are of particular importance in the developing world, where prevalent maternal undernutrition is coupled with persistent infectious challenges. However, early alterations to the immune system, resulting from either nutritional deficiencies or excesses, have broad relevance for immune-mediated diseases, such as asthma, and chronic inflammatory conditions like cardiovascular disease.

The impact of prenatal vitamin A and zinc supplementation on growth of children up to 2 years of age in rural Java, Indonesia

OBJECTIVE

To determine whether prenatal vitamin A and/or Zn supplementation affects postnatal growth.

DESIGN

Follow-up of a randomized controlled trial monitoring growth in children from birth up to 24 months of age.

SETTING

Central Java, Indonesia.

SUBJECTS

Children (n 343) of mothers participating in a double-blinded, randomized controlled study of vitamin A and/or Zn supplementation during pregnancy. We report the effects of prenatal supplementation on infant growth, measured as weight-for-age Z-scores (WAZ), height-for-age Z-scores (HAZ) and weight-for-height Z-scores (WHZ ), from 0 to 24 months, as well as differences in growth faltering among the supplementation groups.

RESULTS

For HAZ, the absolute differences between the vitamin A-only and vitamin A + Zn groups at 3 and 9 months were 0·34 SD and 0·37 SD, respectively, and the absolute difference between the vitamin A-only and Zn-only groups at 18 months was 0·31 SD. Compared with placebo, none of the supplements affected growth. Defining growth faltering as a downward crossing of two or more major percentile lines, 50-75% of the children were found to be growth faltering within 9 months of age, whereas 17% and 8% scored <-2 SD for WAZ and HAZ, respectively. Prenatal supplementation did not reduce the prevalence of growth faltering.

CONCLUSIONS

Prenatal vitamin A supplementation had a small but significant effect on postnatal growth of children's length until 18 months of age compared with supplementation with either vitamin A + Zn or Zn alone, but not compared with placebo. It had no effects on other anthropometric measures and did not reduce the prevalence of growth faltering. Future studies should duplicate these findings before recommendations can be made.

Maternal iron and zinc supplementation during pregnancy affects body weight and iron status in rat pups at weaning

Pregnant women worldwide are frequently iron (Fe) and zinc (Zn) deficient. Therefore, cosupplementation with Fe and Zn during pregnancy is common. Although Fe supplementation programs are successful, studies suggest that Zn supplementation negatively affects maternal Fe metabolism. However, little is known about the effects of maternal Fe or Zn supplementation on Fe metabolism in the offspring. We developed a rat model to investigate if Fe and/or Zn supplementation during pregnancy affects regulation of nonheme Fe absorption and Fe status in offspring and if these effects are dependent upon maternal Fe and Zn status at conception. Control (C; fed a Fe- and Zn-adequate diet; 75 and 25 μg/g, respectively) or Fe- and Zn-deficient (D; fed a Fe- and Zn-deficient diet; 12 and 10 μg/g, respectively) rats were supplemented with Fe (27 mg/wk), Zn (4.5 mg/wk), Fe+Zn (27 mg Fe, 4.5 mg Zn/wk), or placebo throughout pregnancy. At postnatal d 21, body weight (BW), hemoglobin (Hb), hematocrit (Hct), liver and intestine Fe concentration, liver hepcidin, and intestine Fe transporter expression were determined in pups. Zn supplementation of C dams decreased pup BW (P < 0.0001), whereas it increased pup BW in D dams (P < 0.0001). Zn supplementation of C dams did not affect Hb and Hct in pups but increased the liver Fe concentration (P = 0.0002). However, Zn supplementation of D dams decreased hepcidin expression in their offspring (P < 0.0001). In C dams, Fe and Fe+Zn supplementation decreased ferroportin levels in pup intestine compared with pups from unsupplemented dams (P < 0.05). In conclusion, Zn supplementation of dams with adequate Fe and Zn status increases offspring liver Fe concentration and postnatally compromises BW. Therefore, potential adverse effects of Zn supplementation should be evaluated.

Zinc restriction during different periods of life: influence in renal and cardiovascular diseases

Micronutrient undernutrition during critical periods of growth has become an important health issue in developing and developed countries, particularly among pregnant women and children having an imbalanced diet. Zinc is a widely studied microelement in infant feeding because it is a component of several enzymes involved in intermediary metabolism ranging from growth to cell differentiation and metabolism of proteins, carbohydrates, and lipids. Human and experimental studies have reported an association between zinc deficiency and the etiopathogenesis of cardiovascular and renal diseases like hypertension, atherosclerosis, congestive heart failure, coronary heart disease, and diabetes. The main links between the development of these pathologies and zinc deficiency are multiple mechanisms involving oxidative stress damage, apoptosis, and inflammation. A substantial body of evidence suggests that a poor in utero environment elicited by maternal dietary or placental insufficiency may "programme" susceptibility in the fetus to later development of cardiovascular, renal, metabolic, and endocrine diseases. Zinc deficiency in rats during intrauterine and postnatal growth can also be considered a model of fetal programming of cardiovascular and renal diseases in adult life. Dietary zinc restriction during fetal life, lactation, and/or postweaning induces an increase in arterial blood pressure and impairs renal function in adult life. This review focuses on the contributions of experimental and clinical studies to current knowledge of the physiologic role of zinc in the cardiovascular and renal systems. Moreover, this review examines the relationship between zinc deficiency during different periods of life and the development of cardiovascular and renal diseases in adult life.

Micronutrients, birth weight, and survival

Maternal micronutrient requirements during pregnancy increase to meet the physiologic changes in gestation and fetal demands for growth and development. Maternal micronutrient deficiencies are high and coexist in many settings, likely influencing birth and newborn outcomes. The only recommendation for pregnancy currently exists for iron and folic acid use. Evidence is convincing that maternal iron supplementation will improve birth weight and perhaps gestational length. In one randomized trial, iron supplementation during pregnancy reduced child mortality in the offspring compared with the control group. Few other single micronutrients given antenatally, including vitamin A, zinc, and folic acid, have been systematically shown to confer such a benefit. A meta-analysis of 12 trials of multiple micronutrient supplementation compared with iron-folic acid reveals an overall 11% reduction in low birth weight but no effect on preterm birth and perinatal or neonatal survival. Currently, data are unconvincing for replacing supplementation of antenatal iron-folic acid with multiple micronutrients.

Zinc fortification of cereal flours: current recommendations and research needs

BACKGROUND

Zinc fortification is recommended as an appropriate strategy to enhance population zinc status, but guidelines are needed on the appropriate types and levels of zinc fortification of cereal flours for mass fortification programs.

OBJECTIVE

To review available information on the scientific rationale, efficacy, and effectiveness of zinc fortification programs, and to develop guidelines on appropriate levels of fortification of cereal flours, based on simulations of the amount of zinc absorbed under different dietary conditions and information on possible adverse effects.

METHODS

Systematic review of scientific literature and application of an existing prediction equation to estimate zinc absorption.

RESULTS

Previously completed research demonstrates that zinc intake and absorption are increased when zinc-fortified foods are consumed, but little information is, as yet, available on the biologic impact of large-scale fortification programs. Studies suggest that there are no disadvantages of the recommended ranges of zinc fortification with regard to the sensory properties of zinc-fortified foods, and most research indicates that there are no adverse effects of zinc fortification on the utilization of other minerals.

CONCLUSIONS

Zinc fortification of cereal flour is a safe and appropriate strategy for enhancing the zinc status of population subgroups who consume adequate amounts of fortified cereal flour, although additional information is needed to confirm the efficacy and effectiveness of large-scale zinc fortification programs to control zinc deficiency. The appropriate level of fortification depends on the population subgroup, their usual amount of flour intake, the degree of milling and fermentation that is practiced, and the usual intakes of zinc and phytate from other food sources. Fortification recommendations are presented for different dietary scenarios.

Gestational nutrition improves outcomes of vaginal deliveries in Jordan: an epidemiologic screening

Adequate and balanced nutrition during gestation is essential for achieving healthy pregnancy outcomes. This retrospective survey tested the hypothesis that maternal nutrition (macronutrients intake, micronutrients intake, and weight gain) during gestation will impact gestational outcomes (gestational age, birth weight, and labor spontaneity). The objectives of this study were to test the impact of macronutrients and micronutrients consumed during gestation, pregestational weight and weight gain during gestation on gestational age, birth weight, and labor spontaneity among Jordanian women. Study participants (n = 700) were recruited from a women's hospital in northern Jordan. Data were collected using structured interviews. Dietary determinants examined in the study included daily intake of macronutrients (energy, carbohydrate, protein, fat, and n-3 and n-6 fatty acids) and micronutrients (zinc, calcium, folate, vitamin C, vitamin A, and vitamin B6), pregestational body mass index, total weight gain, and weight gain pattern during pregnancy. Dietary data were obtained from a semiquantitative food frequency questionnaire. Mean (SEM) daily intakes of energy, carbohydrate, and protein were 10894 (138) Kj, 320 (3.8) g, and 90 (0.95) g, respectively; with fat contributing 36% of total energy. Average daily energy and carbohydrate intake during pregnancy were related negatively to gestational age (P < .05). Pregestational body mass index was associated positively with gestational age and birth weight (P < .05). Intakes of vitamin A and calcium had significant relationships with birth weight. Daily intakes of zinc, calcium, vitamin B6, and n-3 and n-6 fatty acids were associated with labor spontaneity. Dietary factors consumed during pregnancy are associated with pregnancy outcomes.

Maternal gestational zinc supplementation does not influence multiple aspects of child development at 54 mo of age in Peru

BACKGROUND

Zinc is necessary for central nervous system development, and maternal zinc status has been associated with developmental differences in offspring.

OBJECTIVE

The objective was to evaluate differences in cognitive, social, and behavioral function in Peruvian children at 54 mo of age whose mothers participated during pregnancy in a zinc supplementation trial.

DESIGN

We attempted to follow up 205 children from a prenatal zinc supplementation trial and present data on 184 (90%) children-86 whose mothers took 25 mg zinc/d in addition to 60 mg iron and 250 microg folic acid and 98 whose mothers took iron and folic acid only. Following a standardized protocol, we assessed children's intelligence, language and number skills, representational ability, interpersonal understanding, and adaptive behavior and behavioral adjustment. We also assessed aspects of the mother (eg, age, education, verbal intelligence, stresses, and social support in parenting) and the home environment [HOME (Home Observation for the Measurement of the Environment) inventory].

RESULTS

No differences were observed between any of the tests used to characterize cognitive, social, or behavioral development (P > 0.05). Child sex, parity, or treatment compliance did not modify the effects of supplementation on any outcomes.

CONCLUSION

The addition of zinc to prenatal supplements did not influence developmental outcomes in Peruvian children when assessed at 4.5 y of age.

Maternal zinc supplementation reduces diarrheal morbidity in peruvian infants

OBJECTIVE

To test whether zinc supplementation during pregnancy would reduce infant morbidity rates.

STUDY DESIGN

A double-blind, randomized controlled trial of prenatal zinc supplementation was conducted from 1995 to 1997 in a periurban slum of Lima, Peru. Participants were randomly assigned to receive daily supplementation with zinc (15 mg zinc + 60 mg iron + 250 microg folic acid) or placebo (60 iron + 250 microg folic acid) from 10 to 24 weeks gestation until 1 month postpartum. Anthropometry was measured monthly from birth through age 12 months, and morbidity and dietary intake were measured weekly from 6 to 12 months (n = 421).

RESULTS

The average percentage of observation days with diarrhea among infants prenatally treated with zinc (5.8%) was reduced compared with infants in the control group (7.7%) (P = .01). Prenatal zinc supplementation reduced the likelihood of an infant experiencing diarrheal episodes of acute diarrhea lasting longer than 7 days (OR 0.66, 95% CI 0.43, 0.99, P = .04) and mucus in the stool (OR 0.65 95% CI 0.46, 0.92, P = .01) adjusting for infant age, breastfeeding, season, and hygiene and sanitation covariates. No treatment effects on respiratory illnesses, fever, or skin conditions were detected.

CONCLUSIONS

Improving prenatal zinc nutrition protected against diarrheal morbidity in infant offspring through 12 months of age.

Changes in copper and zinc plasma concentrations during the normal menstrual cycle in women

OBJECTIVE

To investigate whether there is a fluctuation of the copper and zinc plasma levels during the menstrual cycle and if this correlates to the physiological fluctuations of estradiol and progesterone plasma concentrations in eumenorrhoic women.

METHODS

We studied 14 eumenorrhoic women. Copper (Cu), zinc (Zn), estradiol (E2) and progesterone (Prg) plasma concentrations, during time of menstruation (time 1), midfollicular phase (time 2), time of ovulation (time 3) and midluteal phase (time 4) were determined.

RESULTS

We observed significant changes in both copper plasma concentrations and zinc plasma concentrations during the four times studied (p < 0.05). The changes of Cu during the various phases correlated negatively with the changes in E2 (r > 0.5, p < 0.05), whereas the changes of Zn correlated positively with those of E2 (r > 0.8, p < 0.05). We were unable to demonstrate any statistically significant correlation between Cu and Prg or Zn and Prg.

CONCLUSIONS

This study indicates that there is a cyclic fluctuation of Cu and Zn concentrations in plasma during the menstrual cycle, in healthy eumenorrhoic women. This cyclic fluctuation might be due to the cyclic fluctuation of plasma levels of E2.

A randomized trial to determine the optimal dosage of multivitamin supplements to reduce adverse pregnancy outcomes among HIV-infected women in Tanzania

BACKGROUND

We previously reported that supplementation with multivitamins (vitamin B complex, vitamin C, and vitamin E) at multiples of the Recommended Dietary Allowance (RDA) significantly decreased the risk of adverse pregnancy outcomes among HIV-infected women. The minimum dosage of multivitamins necessary for optimal benefits is unknown.

OBJECTIVE

We investigated the efficacy of multivitamin supplements at single compared with multiple RDAs on decreasing the risk of adverse pregnancy outcomes among HIV-infected women.

DESIGN

We conducted a double-blind, randomized controlled trial among 1129 HIV-infected pregnant women in Tanzania. Eligible women between 12 and 27 gestational weeks were randomly assigned to receive daily oral supplements of either single or multiple RDA multivitamins from enrollment until 6 wk after delivery.

RESULTS

Multivitamins at multiple and single doses of the RDA had similar effects on the risk of low birth weight (11.6% and 10.2%, respectively; P = 0.75). We found no difference between the 2 groups in the risk of preterm birth (19.3% and 18.4%, respectively; P = 0.73) or small-for-gestational-age (14.8% and 12.0%, respectively; P = 0.18). The mean birth weights were similar in the multiple RDA (3045 + or - 549 g) and single RDA multivitamins group (3052 + or - 534 g; P = 0.83). There were no significant differences between the 2 groups in the risk of fetal death (P = 0.99) or early infant death (P = 0.19).

CONCLUSION

Multivitamin supplements at a single dose of the RDA may be as efficacious as multiple doses of the RDA in decreasing the risk of adverse pregnancy outcomes among HIV-infected women. This trial was registered at clinicaltrials.gov as NCT00197678.

The role of calcium, magnesium, and zinc in pre-eclampsia

Pre-eclampsia is the most common medical complication of pregnancy associated with increased maternal and infant mortality and morbidity. Its exact etiology is not known, although several evidences indicate that various elements might play an important role in pre-eclampsia. This study was carried out to analyze and to compare the concentration of calcium, magnesium, and zinc in the serum of women with pre-eclampsia and in normal pregnant women. Fifty clinically diagnosed patients with pre-eclampsia (25 with mild and 25 with severe pre-eclampsia) and 50 normal pregnant controls were enrolled in this study. The serum calcium, magnesium, and zinc levels were estimated with an atomic absorption spectrophotometer. The mean serum levels of calcium, magnesium, and zinc in normal pregnant group were 2.45 +/- 0.18 mmol/L, 0.79 +/- 0.13 mmol/L, and 15.64 +/- 2.4 micromol/L, respectively, while in mild pre-eclamptic group, these were 2.12 +/- 0.15 mmol/L, 0.67 +/- 0.14 mmol/L, and 12.72 +/- 1.7 micromol/L, respectively. Serum levels in severe pre-eclamptic group were 1.94 +/- 0.09 mmol/L, 0.62 +/- 0.11 mmol/L, and 12.04 +/- 1.4 micromol/L, respectively. These results indicate that reduction in serum levels of calcium, magnesium, and zinc during pregnancy might be possible contributors in etiology of pre-eclampsia, and supplementation of these elements to diet may be of value to prevent pre-eclampsia.

Galvanizing action: conclusions and next steps for mainstreaming zinc interventions in public health programs

This paper summarizes the results of the foregoing reviews of the impact of different intervention strategies designed to enhance zinc nutrition, including supplementation, fortification, and dietary diversification or modification. Current evidence indicates a beneficial impact of such interventions on zinc status and zinc-related functional outcomes. Preventive zinc supplementation reduces the incidence of diarrhea and acute lower respiratory tract infection among young children, decreases mortality of children over 12 months of age, and increases growth velocity. Therapeutic zinc supplementation during episodes of diarrhea reduces the duration and severity of illness. Zinc fortification increases zinc intake and total absorbed zinc, and recent studies are beginning to confirm a positive impact of zinc fortification on indicators of population zinc status. To assist with the development of zinc intervention programs, more information is needed on the prevalence of zinc deficiency in different countries, and rigorous evaluations of the effectiveness of large-scale zinc intervention programs should be planned. Recommended steps for scaling up zinc intervention programs, with or without other micronutrients, are described. In summary, there is now clear evidence of the benefit of selected interventions to reduce the risk of zinc deficiency, and a global commitment is urgently needed to conduct systematic assessments of population zinc status and to develop interventions to control zinc deficiency in the context of existing public health and nutrition programs.

Effects of maternal zinc supplementation on pregnancy and lactation outcomes

Observational studies in human populations suggest that maternal zinc deficiency during pregnancy may cause adverse pregnancy outcomes for the mother and fetus. Therefore, we reviewed the current evidence from studies of zinc supplementation, with or without other micronutrients, during pregnancy and lactation to assess its impact on maternal, fetal, and infant health. A meta-analysis of supplementation trials indicates a 14% reduction in premature delivery among zinc-supplemented women. Most studies found no significant impact of maternal zinc supplementation on infant birthweight, but a subset of studies conducted in underweight or zinc-deficient women suggests that there may be a positive effect of zinc supplementation in such women. However, the number of relevant studies is limited, and more information is needed to confirm these observations. The results for other pregnancy outcomes are inconsistent, and the number of available studies is small. Likewise, the impact of maternal zinc supplementation during pregnancy on infant postnatal growth and risk of infection is variable, and few studies are available. Thus, more research will be needed to allow definitive conclusions to be drawn, especially for the second half of infancy and later childhood. Studies found no adverse effects of maternal zinc supplementation on iron status during pregnancy. More information is required on other potential adverse effects, particularly with regard to a possible modifying effect of preexisting maternal zinc status. In view of the possible benefits of zinc supplementation for reducing the risk of premature delivery, the possible positive impact of zinc supplementation on infant birthweight among undernourished women, and the lack of reported adverse effects, zinc should be included in maternal supplements given during pregnancy in populations at risk for zinc deficiency.