Relationships of maternal zinc intake from animal foods with fetal growth

L-shaped association between dietary zinc intake and the risk of developing cardiovascular disease in Chinese adults: A cohort study

Background

Although the association of zinc (Zn) with cardiovascular disease (CVD) has been studied, no consensus has been reached on this relationship, particularly dietary Zn intake. The purpose of this study was to assess the effect of dietary Zn intake on the risk of CVD and to analyze whether this effect varied according to zinc consumption using representative data from China.

Methods

11,470 adults from the China Health and Nutrition Survey (CHNS) were eventually enrolled. The dietary information was collected by the 3 day 24-h dietary recalls combined with dietary weighting method. CVD was defined as participants with self-reported physician-diagnosed apoplexy and/or myocardial infarction during the follow-up. Cox regression was used to calculate the hazard ratios (HRs) of CVD with 95% confidence intervals. Restricted cubic spline function plus Cox regression was used to visualize the influence trend of dietary Zn intake on new-onset CVD and to test whether this trend is linear. 2-segment Cox regression was established to address the nonlinear trend.

Results

431 participants developed CVD, including 262 strokes and 197 myocardial infarctions. Compared with the lowest quintile (Q1), the adjusted hazard ratios and 95% confidence interval (CI) of CVD in Q2 to Q5 of dietary Zn intake were 0.72 (0.54, 0.97), 0.59 (0.42, 0.81), 0.50 (0.34, 0.72) and 0.44 (0.27, 0.71), respectively. The influence trend of dietary Zn intake on new-onset CVD was nonlinear and L-shaped. When dietary Zn intake <13.66 mg/day, increased dietary Zn intake was significantly associated with decreased risk of developing CVD (HR = 0.87, 95% CI: 0.82-0.92, p-value <0.0001).

Conclusion

An L-shaped trend was observed between dietary Zn intake and the risk of developing CVD, indicating that dietary Zn intake should be improved moderately, but not excessively, for the benefit of cardiovascular disease.

Association of maternal dietary patterns during pregnancy with small-for-gestational-age infants: Korean Mothers and Children's Environmental Health (MOCEH) study

BACKGROUND

Nutrients that support the desired growth and development of the fetus (i.e., micronutrients like folate, iron, and zinc) have been associated with birth outcomes, such as gestational age at delivery and birth weight.

OBJECTIVES

We characterized the maternal dietary patterns that explain the maximum variation in folate, iron, and zinc intakes in pregnant Korean women using reduced-rank regression (RRR) and investigated the association of these patterns with small-for-gestational-age (SGA) risk.

METHODS

A total of 1158 pregnant Korean women at 12-28 weeks of gestation and their newborns were recruited for the Mothers and Children's Environmental Health (MOCEH) study between 2006 and 2010. A semiquantitative FFQ was collected from the women, and RRR was used to derive their dietary patterns. Log-transformed maternal intakes of folate, iron, and zinc were selected as the intermediate response variables to extract dietary patterns. Infant birth outcome measurements were obtained from hospital records. Associations were assessed by logistic regression with adjustment for confounding factors.

RESULTS

Three dietary patterns were identified. Pattern 1, characterized by high intakes of grains, green/yellow and light-colored vegetables, kimchi, legumes, fruits, meat, eggs, fish, seaweeds, tofu/soymilk, yogurt, and nuts, was associated with a lower risk of SGA in the highest quartile than in the lowest quartile (OR: 0.36; 95% CI: 0.14, 0.94). Especially, maternal dietary pattern 1 was negatively related to high-sensitivity C-reactive protein in the blood and malondialdehyde concentrations in the urine. No association was observed between other dietary patterns and SGA.

CONCLUSION

Among pregnant Korean women, adherence to a dietary pattern characterized by high intakes of grains, green/yellow and light-colored vegetables, kimchi, legumes, fruits, meat, eggs, fish, seaweeds, tofu/soymilk, yogurt, and nuts is associated with a lower risk of delivering SGA infants.

The Influence of Nutrients Intake during Pregnancy on Baby's Birth Weight: A Systematic Review

BACKGROUND AND OBJECTIVE

Maternal food intake during pregnancy can substantially interfere in the baby's anthropometric measurements at birth. Our objective was to perform a systematic review that investigate the influence of nutrient intake via food during pregnancy on the baby's anthropometric measurements at birth.

METHODS

A search was performed without time limits on CINAHL, Embase, PubMed, Scopus and Web of Science databases and manual on studies references. All nutrients and baby's anthropometric measurements at birth were included as descriptors.

RESULTS

Thirty articles were included, the majority of prospective cohort studies, with 15.39 (2.36) quality points (maximum value: 22). Thirty-six results of associations were found, of which 17 studies had direct associations between nutrient intake and birth outcomes. Inverse associations were identified in 8 studies and 11 articles showed no significant associations in all analyses. Maternal food intake of vitamin C, calcium and magnesium during pregnancy seems to have a positive influence on the baby's birth weight, while carbohydrates intake have an inverse association with the same outcome.

CONCLUSION

It is suggested that vitamin C, calcium, magnesium and carbohydrates influence on baby's birth weight. So, these specific nutrients need more attention to the consumption, in addition to carried out new studies, with robust methodologies for measuring maternal food consumption and considering the several factors that can interfere in this assessment.

REGISTRATION

This review has been registered to the PROSPERO (International prospective register of systematic reviews) (ID: CRD42020167889).

Comparison of birth weights of neonates of mothers receiving vs. not receiving zinc supplement at pregnancy

Background

Zinc is an essential element for normal embryogenesis and embryonic and neonatal development. Therefore, we compared the birth weights of neonates born to mothers who consumed zinc supplement during pregnancy with that of neonates born to mothers who did not.

Methods

In a cross-sectional study, we divided 200 pregnant mothers into two groups: case group (mothers receiving zinc supplement during pregnancy) and control group (mothers not receiving zinc supplement during pregnancy) Then, the neonate’s cord zinc level and mother’s serum level were measured and neonate’s growth charts (weight, height and head circumference)were completed.

Results

In this study, both groups of mothers were observed to have zinc deficiency; 35% of the mothers who consumed zinc supplements and 81% of the mothers who did not consume zinc supplements (P < 0.001). Based on the results, maternal serum of zinc (P < 0.001), neonatal birth weight (P = 0.008), maternal age (P < 0.001) and parity (P < 0.01) in zinc-supplemented group were higher. Neonatal birth weight was associated moderately with mother’s zinc serum levels and poorly with neonatal serum zinc levels.

Conclusion

Zinc consumption during pregnancy increases serum zinc level of mother and neonatal weight. Neonatal weight has a higher correlation to maternal serum zinc level.

Environmental pollutants affecting children's growth and development: Collective results from the MOCEH study, a multi-centric prospective birth cohort in Korea

BACKGROUND

The Mothers and Children's Environmental Health study (MOCEH) is a multi-centric prospective birth cohort study investigating effects of various environmental pollutants like heavy metals, endocrine disruptors, air pollutants, nutrition and lifestyle on birth outcomes, growth and development, health and disease of children. In this study, we report all the outcomes from the MOCEH study describing the different environmental pollutants affecting children's health and disease.

METHODS

In MOCEH study, 1,751 pregnant women in their first trimester were recruited at 3 centers from 2006 to 2010 in South Korea. The children were followed from birth up to 6 years. Information on health outcomes of children including birth parameters, demographic characteristics, medical and child-rearing history, and nutritional status, were repeatedly obtained through the follow-ups by questionnaires administration, clinical evaluation, and biological specimen collection and measurements. Prenatal and postnatal measurement in biospecimen, i.e., lead, mercury, cadmium, manganese, 1-hydroxypyrene, 2-naphthol, malonadialdehyde, hippuric acid, bisphenol A and phthalate metabolites, and measurement in air samples, i.e., particulate matter, nitrogen dioxide, and total volatile organic compounds were performed.

RESULTS

The results show the adverse effect of prenatal exposure to heavy metals like mercury, lead and cadmium on children's physical, cognitive and neurobehavioral development. Exposure to endocrine disruptors, air pollution, second hand smoke, and mother's lifestyle during pregnancy affects children's growth and development. We also identified specific window periods of exposure of pollutants significantly related to children's health outcomes.

CONCLUSION

The collective results from MOCEH study provide strong scientific evidence that exposures to prenatal and postnatal environmental pollutants have a negative effect on growth and development of children, which will be useful in implementing effective national policy to improve children's environmental health.

A Prospective Study of Serum Trace Elements in Healthy Korean Pregnant Women

This prospective study sought to investigate serum levels of trace elements (cobalt, copper, zinc, and selenium) and to assess their effects on pregnancy and neonatal outcomes. Serum levels of trace elements in 245 Korean pregnant women (median gestational age at delivery was 39 + 4 weeks and interquartile range was 38 + 4–40 + 1 weeks) were compared with those of 527 general adults and those of previous studies in other ethnic groups. Pregnancy and neonatal outcomes including gestational diabetes, preeclampsia, neonatal birth weight, and congenital abnormalities were assessed. The median serum trace element concentrations of all pregnant women were: cobalt: 0.39 μg/L (interquartile range, IQR 0.29–0.53), copper: 165.0 μg/dL (IQR 144.0–187.0), zinc: 57.0 μg/dL (IQR 50.0–64.0), and selenium: 94.0 μg/L (IQR 87.0–101.0). Serum cobalt and copper concentrations were higher in pregnant women than in the general population, whereas zinc and selenium levels were lower (p < 0.01). Concentrations of all four trace elements varied significantly during the three trimesters (p < 0.05), and seasonal variation was found in copper, zinc, and selenium, but was not observed for cobalt. The prevalence of preeclampsia was significantly lower with high copper (p = 0.03). Trace element levels varied by pregnancy trimester and season, and alteration in copper status during pregnancy might influence pregnancy outcomes such as preeclampsia.

Nutritional status of pre-pregnant and pregnant women residing in Bogor district, Indonesia: a cross-sectional dietary and nutrient intake study

The diet of Indonesian women of childbearing age is relatively poor, posing increased risk for suboptimal pregnancy outcome. In a cross-sectional study including 403 women in three economic quintiles (Q), we investigated differences in dietary intake and nutrition sufficiency according to economic status and whether regular dietary intakes of pregnant women (PW, n 203) differ from that of pre-pregnant women (PPW, n 200). Dietary intake data were collected using 2×24 h dietary recall and FFQ. Energy, protein, Fe, Ca, Zn, vitamin A and vitamin C intakes were calculated utilising Food Composition Tables and compared with Indonesian recommendations for adequacy. Energy and protein intakes <70 % and Fe, Ca, Zn, vitamin A and vitamin C intakes <77 % of the local recommendation were considered insufficient. A higher intake of milk/dairy products (Q3, Q4), fruits and vegetables (Q2) and snacks (Q3) in PW was observed compared with PPW, but insufficient to meet nutrient requirements. Nutrient intake calculations showed insufficiency in 26 % of PPW for protein and up to 70 % for Fe. Deficient nutrient intakes in PW were found in 49 % of the subjects for energy and up to 85 % for Fe. Energy and protein intakes decreased with decreasing economic quintiles in PPW and PW. Ca and vitamin A intakes were lower in Q2 compared with Q4. The proportion of animal protein in Q2-PW was low (31 %). Biochemical status parameters in a subset showed that anaemia and Fe and Zn deficiencies were prevalent among PPW and PW. Habitual diets in the study area did not meet the nutrient requirements for both PPW and PW across the investigated economic groups.

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.