Development of a plasma zinc concentration cutoff to identify individuals with severe zinc deficiency based on results from adults undergoing experimental severe dietary zinc restriction and individuals with acrodermatitis enteropathica

Minerals and trace elements in pregnancy in women with previous bariatric surgery consequences on maternal and foetal health

BACKGROUND

Bariatric surgery (BS) may decrease the risk of these obesity-related complications; however, due to its effect on nutrient intake and absorption, it can also have adverse consequences on maternal and foetal health. The aim of this study is to describe the evolution of electrolytes and trace elements serum levels throughout pregnancy after BS, according to the surgical technique and to evaluate the effect of nutritional deficiencies on the risk of maternal-foetal complications.

METHODS

This is a retrospective observational study of the clinical evolution and maternal-foetal complications in a group of women with pregnancies that occurred after BS. Clinical evolution during pregnancy, body weight, and plasma electrolytes, vitamins, and trace elements, as well as their influence on maternal-foetal outcomes were evaluated. Composite neonatal variable (CNV) was defined to evaluate unfavourable foetal outcome. Published reference values for micronutrients during pregnancy have been used.

RESULTS

The study includes data on 164 singleton pregnancies in 91 women. A hundred and twenty-seven pregnancies got to full term. The average birth weight was 2966 (546) g., 26.8% < P10 and 13.8% < P3 of a reference population. New-born of gestations after malabsorptive bariatric surgery had a higher risk of having a percentile of birth weight < P3. Plasma electrolytes, trace elements and vitamins throughout pregnancy showed differences depending on the surgical technique, with lower haemoglobin, ferritin, calcium, zinc, copper, vitamin A and vitamin E in the malabsorptive techniques. A high percentage of deficiency was observed, especially in the third trimester (Hb < 11 g/dl: 31.8%; ferritin < 30 mg/ml: 85.7%; zinc < 50 μg/dl: 32.4%, vitamin D < 30 ng/ml: 75.5% and < 20 ng/ml: 53.3%). A decreased plasma copper in the first trimester or zinc in the third trimester were associated with a lower percentile of new-born birth weight. A higher risk of CNV was observed in predominant malabsorptive BS and in pregnancies that had presented at least one vitamin D level lower than 20 ng/ml throughout pregnancy (30.4% vs. 7.1%, p=0.018).

CONCLUSIONS

Trace elements and vitamin deficiencies are common in pregnant women after bariatric surgery, especially of iron, zinc, and vitamin D. These deficiencies might negatively affect foetal development. Further studies are needed to better define the role of micronutrients in maternal-foetal health after bariatric surgery.

Comment on Chao, H.-C. Zinc Deficiency and Therapeutic Value of Zinc Supplementation in Pediatric Gastrointestinal Diseases. Nutrients 2023, 15, 4093

We appreciate the recent review article by Chao H.-C. [...].

Comparison of Published Estimates of the National Prevalence of Iron, Vitamin A, and Zinc Deficiency and Sources of Inconsistencies

Micronutrient deficiencies result in a broad range of adverse health and functional consequences, but the true prevalence of specific deficiencies remains uncertain because limited information is available from nationally representative surveys using recommended biomarkers. The present review compares various reported national deficiency prevalence estimates for nutrients and years where the estimates overlap for individual countries that conducted nationally representative surveys and explores possible reasons for any discrepancies discovered. Nationally representative micronutrient status surveys that were conducted since 2000 among preschool-aged children or women of reproductive age and included assessment of iron, vitamin A, or zinc status based on recognized biomarkers were considered eligible for inclusion, along with any modeled deficiency prevalence estimates for these same countries and years. There was considerable variation across different published prevalence estimates, with larger inconsistencies when the prevalence estimate was based on proxies, such as hemoglobin for iron deficiency and dietary zinc availability for zinc deficiency. Numerous additional methodological issues affected the prevalence estimates, such as which biomarker and what cutoff was used to define deficiency, whether the biomarker was adjusted for inflammation, and what adjustment method was used. For some country-years, the various approaches resulted in fairly consistent prevalence estimates. For other country-years, however, the results differed markedly and changed the conclusions regarding the existence and severity of the micronutrient deficiency as a public health concern. In conclusion, to determine micronutrient status, we consider the assessment of one of the recommended biomarkers in a population representative survey as the best available information. If indicated, results should be adjusted for inflammation and generally acceptable cutoffs should be applied to facilitate comparisons, although individual countries may also apply nationally defined cutoffs to determine when and where to intervene. Global consensus is needed on best practices for presenting survey results and defining the prevalence of deficiency.

The Effect of Zinc Biofortified Wheat Produced via Foliar Application on Zinc Status: A Randomized, Controlled Trial in Indian Children

BACKGROUND

Agronomic zinc biofortification of wheat by foliar application increases wheat zinc content and total zinc absorption in humans.

OBJECTIVES

To assess the effect of agronomically biofortified whole wheat flour (BFW) on plasma zinc (PZC) compared with a postharvest fortified wheat (PHFW) and unfortified control wheat (CW) when integrated in a midday school meal scheme.

METHODS

We conducted a 20-wk double-blind intervention trial in children (4-12 y, n = 273) individually randomly assigned to 3 groups to receive a daily school lunch consisting of 3 chapattis prepared with the 3 different wheat flour types. Measurements of anthropometry, blood biochemistry, and leukocyte DNA strand breaks were conducted. We applied sparse serial sampling to monitor PZC over time, and analysis was performed using linear mixed-effects models.

RESULTS

Mean zinc content in BFW, PHFW, and CW were 48.0, 45.1, and 21.2 ppm, respectively (P < 0.001). Mean (standard deviation) daily zinc intakes in the study intervention in BFW, PHFW, and CW groups were 4.4 (1.6), 5.9 (1.9) and 2.6 (0.6) mg Zn/d, respectively, with intake in groups PHFW and BFW differing from CW (P < 0.001) but no difference between BFW and PHFW. There were no time effect, group difference, or group × time interaction in PZC. Prevalence of zinc deficiency decreased in the BFW (from 14.1%-11.2%), PHFW (from 8.9%-2.3%), and CW (9.8%-8.8%) groups, but there was no time × treatment interaction in the prevalence of zinc deficiency (P = 0.191). Compliance with consuming the study school meals was associated with PZC (P = 0.006). DNA strand breaks were not significantly associated with PZC (n = 51; r = 0.004, P = 0.945).

CONCLUSIONS

Consumption of either PHFW or BFW provided an additional ∼1.8 to 3.3 mg Zn/d, but it did not affect PZC or zinc deficiency, growth, or DNA strand breaks. This trial was registered on clinicaltrials.gov as NCT02241330 and ctri.nic.in as CTRI/2015/06/005913.

Biofortified Yellow-Fleshed Potatoes Provide More Absorbable Zinc than a Commonly Consumed Variety: A Randomized Trial Using Stable Isotopes in Women in the Peruvian Highlands

BACKGROUND

Zinc-biofortified potatoes have considerable potential to reduce zinc deficiency because of their low levels of phytate, an inhibitor of zinc absorption, and their high consumption, especially in the Andean region of Peru.

OBJECTIVES

The purpose of this study was to measure fractional and total zinc absorption from a test meal of biofortified compared with regular potatoes.

METHODS

We undertook a single-blinded randomized crossover study (using 67Zn and 70Zn stable isotopes) in which 37 women consumed 500-g biofortified or regular potatoes twice a day. Urine samples were collected to determine fractional and total zinc absorption.

RESULTS

The zinc content of the biofortified potato and regular potato was 0.48 (standard deviation [SD]: 0.02) and 0.32 (SD: 0.03) mg/100 g fresh weight, respectively. Mean fractional zinc absorption (FZA) from the biofortified potatoes was lower than from the regular potatoes, 20.8% (SD: 5.4%) and 25.5% (SD: 7.0%), respectively (P < 0.01). However, total zinc absorbed was significantly higher (0.49; SD: 0.13 and 0.40; SD: 0.11 mg/500 g, P < 0.01, respectively).

CONCLUSIONS

The results of this study demonstrate that biofortified potatoes provide more absorbable zinc than regular potatoes. Zinc-biofortified potatoes could contribute toward reducing zinc deficiency in populations where potatoes are a staple food. This trial was registered at clinicaltrials.gov as NCT05154500.

Biological Role of Zinc in Liver Cirrhosis: An Updated Review

Liver cirrhosis is a complication usually due to the consequence of persistent chronic liver disease. It is associated with different mechanisms, including hypoalbuminemia, impaired amino acid turnover, and micronutrient deficiencies. Consequently, cirrhotic patients can develop progressive complications like ascites, hepatic encephalopathy, and hepatocellular carcinoma. The liver is a vital organ that regulates the different metabolic pathways and transportation of trace elements. Zn is an indispensable micronutrient trace element involved in its crucial functions in cellular metabolic activity. Zn mediates its action by binding to a wide range of proteins; therefore, it imparts numerous biological effects, including cellular division, differentiation, and growth. It is also involved in critical processes for the biosynthesis of structural proteins and regulation of transcription factors and acts as a co-factor for the various enzymatic processes. As the liver is a significant regulator of Zn metabolism, its abnormalities lead to Zn deficiency, which has consequences on cellular, endocrine, immune, sensory, and skin dysfunctions. Conversely, Zn deficiency may modify the functions of hepatocytes and immune responses (acute phase protein production) in inflammatory liver diseases. This review has concisely stated the evolving indication of the critical role of Zn in biological processes and complications associated with liver cirrhosis pathogenesis due to Zn deficiency.

Vegan nutrition: a preliminary guide for health professionals

Since the beginning of the 21st century, interest in vegan diets has been rapidly increasing in most countries. Misconceptions about vegan diets are widespread among the general population and health professionals. Vegan diets can be health-promoting and may offer certain important advantages compared to typical Western (and other mainstream) eating patterns. However, adequate dietary sources/supplements of nutrients of focus specific to vegan diets should be identified and communicated. Without supplements/fortified foods, severe vitamin B12 deficiency may occur. Other potential nutrients of focus are calcium, vitamin D, iodine, omega-3 fatty acids, iron, zinc, selenium, vitamin A, and protein. Ensuring adequate nutrient status is particularly important during pregnancy, lactation, infancy, and childhood. Health professionals are often expected to be able to provide advice on the topic of vegan nutrition, but a precise and practical vegan nutrition guide for health professionals is lacking. Consequently, it is important and urgent to provide such a set of dietary recommendations. It is the aim of this article to provide vegan nutrition guidelines, based on current evidence, which can easily be communicated to vegan patients/clients, with the goal of ensuring adequate nutrient status in vegans.

Reference cut-offs to define low serum zinc concentrations in healthy 1-19 year old Indian children and adolescents

BACKGROUND/OBJECTIVES

Population zinc (Zn) status assessment is based on serum zinc concentration (SZC) cut-offs defined by the International Zinc Nutrition Consultative Group (IZiNCG). The objective of this study is to derive reference SZC cut-offs in apparently healthy 1-19 year Indian children and adolescents using comprehensive national nutrition survey (CNNS) data, and to measure the prevalence of Zn deficiency.

SUBJECTS/METHODS

Apparently healthy children (n = 12,473) were selected from the CNNS, by including the highest 2 wealth quintiles, and excluding stunted, thin and obese children, and those with CRP > 5 mg/L, anaemia, hypo-albuminemia, diabetes, recent diarrhoea and history of smoking. The 2.5th centile of age-based distributions defined the SZC cut-offs, used to measure the prevalence of Zn deficiency in India, as against the IZiNCG cut-offs.

RESULTS

The present study SZC cut-offs were significantly lower, by 10-18 µg/dL, than the IZiNCG cut-offs; more in adolescents. Prevalence of Zn deficiency in the entire CNNS, with these cut-offs, was 2.7 (<10 years) to 5.5 (10-19 years) times lower than with the IZiNCG cut-offs. No geographical state, nor any age group, had Zn deficiency as a serious public health problem (≥20%). In contrast, with IZiNCG cut-offs, 9-27 states (depending on age group) had a public health problem.

CONCLUSIONS

The present study reference SZC cut-offs for Zn deficiency are lower than the IZiNCG cut-offs, and their rigorous selection from a national sample makes them more appropriate for use in India. A re-examination of the global applicability of IZiNCG recommended cut-offs in other LMICs appears appropriate.

Δ5 and Δ6 desaturase indices are not associated with zinc intake as determined by dietary assessment or modified by a zinc-FADS1 rs174547 SNP interaction in young Canadian adults

BACKGROUND

Zinc is an essential trace mineral that serves as a cofactor for the delta-5 and delta-6 desaturases (D5D, D6D) that are critical for long-chain polyunsaturated fatty acid (LC-PUFA) synthesis. While plasma zinc levels are generally reported to be associated with D5D and D6D indices in humans, it remains unclear if dietary zinc intake can be similarly associated with desaturase indices. Therefore, the present investigation examined if zinc intake determined by food frequency questionnaire (FFQ) is associated with desaturase indices in young Canadian adults. Additionally, we explored whether desaturase indices were modified by an interaction between dietary zinc intake and a common variant in the FADS1 gene.

METHODS

Dietary zinc intake (FFQ), plasma fatty acids (gas chromatography) and the FADS1 rs174547 polymorphism were analyzed in young men and women (n = 803) from the cross-sectional Toronto Nutrigenomics and Health Study. Product-to-precursor fatty acid ratios were used to determine desaturase enzyme indices (D5D = 20:4n-6/20:3n-6; D6D = 18:3n-6/18:2n-6). Individuals were grouped according to dietary zinc intake, as well as by their rs174547 genotype (TT vs. TC+CC). Data were analyzed by 1-way and 2-way ANCOVA.

RESULTS

Plasma fatty acids and D5D/D6D indices did not differ between individuals grouped according to dietary zinc intake. Further, the recently proposed biomarker of zinc intake, 20:3n-6/18:2n-6, was not associated with dietary zinc intake. Although the FADS1 rs174547 SNP was significantly associated with D5D and D6D indices in both men and women (p < 0.0001), we did not find evidence of a dietary zinc intake - FADS1 SNP interaction on D5D or D6D indices.

CONCLUSION

Dietary zinc intake, as determined using FFQs, does not predict differences in desaturase indices, irrespective of FADS1 genotype.

Role of Zinc in Diabetic Kidney Disease

Diabetic Kidney Disease (DKD) represents the most common cause of Chronic Kidney Disease (CKD) in developed countries. Approximately 30% to 40% of diabetes mellitus (DM) subjects develop DKD, and its presence significantly increases the risk for morbidity and mortality. In this context, Zinc seems to have a potential role in kidney and body homeostasis in diabetic individuals as well as in patients at a high risk of developing this condition. This essential element has functions that may counteract diabetes-related risk factors and complications, which include stabilization of insulin hexamers and pancreatic insulin storage and improved glycemic control. In our review, we analyzed the current knowledge on the role of zinc in the management of renal impairment in course of DM. Several studies underline the critical role of zinc in reducing oxidative stress levels, which is considered the common denominator of the mechanisms responsible for the progression of kidney disease. Reaching and maintaining a proper serum zinc level could represent a valuable target to reduce symptoms related to DM complications and contrast the progression of kidney impairment in patients with the high risk of developing end-stage renal disease. In conclusion, analyzing the beneficial role of zinc in this review would advance our knowledge on the possible strategies of DM and DKD treatment.

Zinc supplementation and its benefits in the management of chronic liver disease: An in-depth literature review

Malnutrition among patients with chronic liver disease (CLD) is a common complication with significant prognostic implications for patients with liver cirrhosis. Micronutrient deficiency has been associated with an increased risk of hepatic decompensation and is an independent risk factor for mortality among cirrhotic patients. Micronutrient deficiencies in patients with CLD include zinc, vitamin A, vitamin D and selenium. This review article aims to evaluate the literature to date on the complications of zinc deficiency in patients with CLD. A management algorithm for zinc replacement has also been proposed.

Prevalence and Correlates of Zinc Deficiency Among Vietnamese Women of Reproductive Age in Ho Chi Minh City: A Single Hospital-Based Survey

Background and Objectives: Zinc is a micronutrient that plays an important role in metabolism, cell growth regulation, and differentiation. Vietnam has many population groups living in poverty. The daily food of Vietnamese people is mainly rice, which contains very little zinc. This cross-sectional study was conducted to determine the prevalence of, and factors related to, zinc deficiency in women of reproductive age.

Methods and Study Design: The sample population was non-pregnant women of reproductive age (18–49 years old) who visited Nguyen Tri Phuong Hospital Gynecological Outpatient Clinic. The subjects were interviewed and data on background characteristics, anthropometric measurements, and blood tests (serum zinc concentration, complete blood count, albumin, and ferritin) were collected.

Results: The prevalence of zinc deficiency, as defined by the International Zinc Nutrition Consultative Group (IZiNCG), was 85% [61/72; 95% confidence interval (CI) = 74–91%], and the prevalence of severe zinc deficiency was 37% (27/72; 95% CI = 26–50%). There were significant associations of albumin concentration, marital status, and past pregnancy history with severe zinc deficiency.

Conclusions: More than three-fourths of Vietnamese women of reproductive age had zinc deficiency at our study site in Ho Chi Minh City. This health issue requires greater attention in order to swiftly promote preventive actions, and further surveillance to confirm our study findings.

The effect of zinc-biofortified rice on zinc status of Bangladeshi preschool children: a randomized, double-masked, household-based, controlled trial

BACKGROUND

Zinc biofortification of rice could sustainably improve zinc status in countries where zinc deficiency is common and rice is a staple, but its efficacy has not been tested. Fatty acid desaturases (FADS) are putative new zinc status biomarkers.

OBJECTIVES

Our objective was to test the efficacy of zinc-biofortified rice (BFR) in preschool-aged children with zinc deficiency. Our hypothesis was that consumption of BFR would increase plasma zinc concentration (PZC).

METHODS

We conducted a 9-mo, double-masked intervention trial in 12-36-mo-old rural Bangladeshi children, most of whom were zinc-deficient (PZC <70 µg/dL) and stunted (n = 520). The children were randomly assigned to receive either control rice (CR) or BFR provided in cooked portions to their households daily, with compliance monitoring. The primary outcome was PZC. Secondary outcomes were zinc deficiency, linear growth, infection-related morbidity, FADS activity indices, intestinal fatty acid binding protein (I-FABP) and fecal calprotectin. We applied sparse serial sampling for midpoint measures and analyzed data by intention-to-treat using mixed-effects models.

RESULTS

At baseline, median (IQR) PZC was 60.4 (56.3-64.3) µg/dL, 78.1% of children were zinc deficient, and 59.7% were stunted. Mean ± SD daily zinc intakes from the CR and BFR during the trial were 1.20 ± 0.34 and 2.22 ± 0.47 mg/d, respectively (P < 0.001). There were no significant time-by-treatment effects on PZC, zinc deficiency prevalence, FADS activity, I-FABP, or fecal calprotectin (all P > 0.05). There was a time-treatment interaction for height-for-age z-scores (P < 0.001) favoring the BFR group. The morbidity longitudinal prevalence ratio was 1.08 (95% CI: 1.05, 1.12) comparing the BFR and CR groups, due to more upper respiratory tract illness in the BFR group.

CONCLUSIONS

Consumption of BFR for 9 mo providing ∼1 mg of additional zinc daily to Bangladeshi children did not significantly affect PZC, prevalence of zinc deficiency, or FADS activity.The trial was registered at clinicaltrials.gov as NCT03079583.

Prevalence of Zinc Deficiency in Healthy 1-3-Year-Old Children from Three Western European Countries

Zinc deficiency (ZnD) has adverse health consequences such as stunted growth. Since young children have an increased risk of developing ZnD, it is important to determine its prevalence and associated factors in this population. However, only a few studies have reported on ZnD prevalence in young children from Western high-income countries. This study evaluated ZnD prevalence and associated factors, including dietary Zn intake, in healthy 1–3-year-old children from Western European, high-income countries. ZnD was defined as serum Zn concentration <9.9 µmol/L. A total of 278 children were included with a median age of 1.7 years (Q1–Q3: 1.2–2.3). The median Zn concentration was 11.0 µmol/L (Q1–Q3: 9.0–12.2), and ZnD prevalence was 31.3%. No significant differences were observed in the socio-economic characteristics between children with and without ZnD. Dietary Zn intake was not associated with ZnD. ZnD is common in healthy 1–3-year-old children from Western European countries. However, the use of currently available cut-off values defining ZnD in young children has its limitations since these are largely based on reference values in older children. Moreover, these values were not evaluated in relation to health consequences, warranting further research.

Serum zinc status is a matter of concern among children and non-pregnant women in a nationwide survey of Nepal

Nationally representative population data on zinc status in Nepal is lacking at present. This study analyzed data from the recent Nepal National Micronutrient status survey 2016 to determine the prevalence of zinc deficiency and associated risk factors among children aged 6–59 months (n = 1462) and non-pregnant women aged 15–49 years (n = 1923). Venous blood was collected from the participants to measure micronutrients such as zinc, markers of anemia, RBP (vitamin A), and markers of inflammation. Stool samples were collected to assess soil-transmitted helminths and Helicobacter pylori infection. Socio-demographic, household, and other relevant factors were collected by a structured questionnaire. Serum zinc concentration was measured by Microwave Plasma Atomic Emission Spectrometry, and zinc deficiency was defined according to the International Zinc Nutrition Consultative Group’s guidelines. Logistic regression was used to examine the predictors of zinc deficiency among the participants. The overall zinc deficiency in children was 22.9%, while it was higher in non-pregnant women (24.7%). The prevalence of anemia among zinc-deficient children was higher (21.3%) than the zinc non-deficit children (18.7%). The prevalence of anemia was 18% among zinc-deficient non-pregnant women compared to 22% non-deficit non-pregnant women. Predictors associated with zinc deficiency among the study children were living in rural areas (AOR = 2.25, 95% CI, [1.13, 4.49]), the occurrence of diarrhea during the two weeks preceding the survey (AOR = 1.57, 95% CI, [1.07, 2.30]), lowest household wealth quintile (AOR = 0.48, 95% CI, [0.25, 0.92]) and lower vitamin A status (AOR = 0.49, 95% CI, [0.28, 0.85]. The predictors associated with zinc deficiency among non-pregnant women were: being underweight (AOR = 1.55, 95% CI, [1.12, 2.15]), fever occurrence during two weeks preceding the survey (AOR = 1.43, 95% CI, [1.04, 1.98]), H. pylori in the stool (AOR = 1.33, 95% CI, [1.04, 1.71]), lowest household wealth quintile (AOR = 0.62, 95% CI,[0.40, 0.94]) and being at risk of folate deficiency (AOR = 0.58, 95% CI,[0.36, 0.94]). We conclude that community-level intervention programs focused on rural children and women to prevent diarrhea, improve nutrition counseling, and provide economic opportunities in rural communities may help to lower zinc deficiency and other micronutrient deficiencies in the Nepalese population. We believe that intervention programs to address zinc deficiency should not be isolated. Instead, integrated approaches are beneficial to improve overall micronutrient status, such as encouraging dietary diversity, providing livelihood opportunities to the unemployed, micronutrient supplementation to vulnerable populations, and consumption of zinc-rich animal-based foods.

Micronutrients Deficiency, Supplementation and Novel Coronavirus Infections-A Systematic Review and Meta-Analysis

BACKGROUND

Micronutrients play roles in strengthening and maintaining immune function, but their supplementation and/or deficiency effects on respiratory tract infections are inconclusive. This review aims to systematically assess the associations between micronutrient supplementation or deficiency, with novel coronavirus incidence and disease severity.

METHODS

Systematic literature searches conducted in five electronic databases identified 751 unique studies, of which 33 studies (five supplementation studies, one supplementation and deficiency study, and 27 deficiency studies) were eventually included in this review. Proportions of incidence and severity outcomes in each group, and adjusted summary statistics with their relevant 95% confidence intervaIs (CI) were extracted. Data from 19 studies were pooled in meta-analysis using the generic inverse variance method.

FINDINGS

A total of 360,346 patients across 16 countries, with a mean age between 32 and 87.7 years, were involved across 33 studies. All studies were on COVID-19 infections. In individuals without micronutrient deficiency, there was a significant reduction on odds of COVID-19 incidence (pooled OR: 0.37, 95% CI: 0.18, 0.78), and ICU admissions or severe/critical disease onset when combined as a severity outcome (pooled OR: 0.26, 95% CI: 0.08, 0.89). Insignificant protective effects were observed on other outcome measures, namely mortality, ICU admission, progression to respiratory-related complications, severe/critical disease onset or requiring respiratory support and hospitalization rate.

CONCLUSION

The absence of micronutrient deficiency significantly reduced COVID-19 incidence and clinical deterioration in hospitalized patients. Usage of micronutrients as prophylaxis and complementary supplement in therapeutic management of COVID-19 patients may be a promising and cost-effective approach warranting in-depth investigation.

Zinc Nutritional Status in a Series of Children with Chronic Diseases: A Cross-Sectional Study

BACKGROUND

Zinc is an essential trace element for the normal growth and development of human beings. The main objective was to evaluate the nutritional status of zinc and its association with nutritional indicators in a series of children with chronic diseases.

METHODS

The prevalence of patients with dietary zinc deficiency or deficit zinc intake (<80% DRI: dietary reference intake) was analyzed through prospective 72 h dietary surveys, and serum zinc deficiency or hypozincemia (≤70 µg/dL in children under 10 years of age in both sexes and in females older than 10 years and <74 μg/dL in males older than 10 years) was measured through atomic absorption spectrophotometry. The participants were classified according to their nutritional status by body mass index (BMI).

RESULTS

Mean serum zinc level in obese (87 µg/dL), undernourished (85 µg/dL), and eutrophic children (88 µg/dL) were normal, but in the undernutrition (60% DRI) and eutrophic (67% DRI) groups the mean dietary zinc intake was low compared to that in the obesity group (81% DRI). There were different associations between nutritional parameters, dietary zinc intake, and serum zinc. All patients with hypozincemia had dietary zinc deficiency.

CONCLUSIONS

In the whole series, 69% of participants showed a zinc intake lower than recommended and might be at high risk of zinc deficiency.

Associations between Zinc and Hemoglobin Concentrations in Preschool Children and Women of Reproductive Age: An Analysis of Representative Survey Data from the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) Project

BACKGROUND

Anemia is a worldwide concern. Nutritional deficiencies and inflammation are considered main contributors, but zinc deficiency has only recently been associated with anemia.

OBJECTIVES

In this study we assessed associations between zinc status and hemoglobin (Hb) concentrations and anemia in preschool children 6-59 mo old (PSC) and nonpregnant women of reproductive age 15-49 y old (WRA) in population-based nutrition surveys.

METHODS

Cross-sectional data from 13 (PSC) and 12 (WRA) countries within the Biomarkers Reflecting Inflammation and Nutritional Determinants of Anemia (BRINDA) project were used. Multivariable linear models were constructed that included zinc status (plasma/serum zinc concentrations), Hb concentrations and anemia, iron status, age, sex, and inflammation (C-reactive protein and α-1-acid glycoprotein). Zinc was adjusted for inflammation in PSC according to the BRINDA algorithm.

RESULTS

Data were available for 18,658 PSC and 22,633 WRA. Prevalence of anemia ranged from 7.5% to 73.7% and from 11.5% to 94.7% in PSC and WRA, respectively. Prevalence of zinc deficiency ranged from 9.2% to 78.4% in PSC and from 9.8% to 84.7% in WRA, with prevalence of zinc deficiency >20% in all countries except Azerbaijan (PSC), Ecuador (PSC), and the United Kingdom (WRA). Multivariable linear regression models showed that zinc concentrations were independently and positively associated with Hb concentrations in 7 of 13 countries for PSC and 5 of 12 countries for WRA. In the same models, ferritin concentration was also significantly associated with Hb among PSC and WRA in 9 and 10 countries, respectively. Zinc deficiency was significantly associated with anemia in PSC and WRA in 5 and 4 countries respectively.

CONCLUSIONS

Zinc deficiency was prevalent in most countries and associations between zinc and Hb in roughly half of the countries examined suggesting that strategies to combat zinc deficiency may help reduce anemia prevalence. More research on mechanisms by which zinc deficiency is associated with anemia and the reasons for the heterogeneity among countries is warranted.

Comprehensive Nutrient Gap Assessment (CONGA): A method for identifying the public health significance of nutrient gaps

Identifying dietary nutrient gaps and interpreting their public health significance are essential for improving poor diets and reducing malnutrition. Evidence indicative of the burden of nutrient deficiencies and inadequate nutrient intake or availability exists in many countries yet is often misinterpreted or underused in decision-making. Clear guidance is lacking on how to synthesize and interpret the relevant evidence, which comes in many forms. To fill this methodological gap, an approach called Comprehensive Nutrient Gap Assessment was created to enable use of existing evidence to assess the public health significance of nutrient gaps and identify evidence gaps. Comprehensive Nutrient Gap Assessment requires ≥ 2 experts in nutritional assessment but does not require primary data collection or secondary quantitative data analysis. It can be implemented relatively quickly with low costs, for specific countries and subnational regions, and updated on the basis of new data with minimal effort. The findings from a Comprehensive Nutrient Gap Assessment are easily interpretable by nontechnical decision makers yet include clear justification for technical audiences.

Low Zinc Levels at Admission Associates with Poor Clinical Outcomes in SARS-CoV-2 Infection

Background: Zinc is an essential micronutrient that impacts host–pathogen interplay at infection. Zinc balances immune responses, and also has a proven direct antiviral action against some viruses. Importantly, zinc deficiency (ZD) is a common condition in elderly and individuals with chronic diseases, two groups with an increased risk for severe severe coronavirus disease 2019 (COVID-19) outcomes. We hypothesize that serum zinc content (SZC) influences COVID-19 disease progression, and thus might represent a useful biomarker. Methods: We ran an observational cohort study with 249 COVID-19 patients admitted in Hospital del Mar. We have studied COVID-19 severity and progression attending to SZC at admission. In parallel, we have studied severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) replication in the Vero E6 cell line modifying zinc concentrations. Findings: Our study demonstrates a correlation between serum zinc levels and COVID-19 outcome. Serum zinc levels lower than 50 µg/dL at admission correlated with worse clinical presentation, longer time to reach stability, and higher mortality. Our in vitro results indicate that low zinc levels favor viral expansion in SARS-CoV-2 infected cells. Interpretation: Low SZC is a risk factor that determines COVID-19 outcome. We encourage performing randomized clinical trials to study zinc supplementation as potential prophylaxis and treatment with people at risk of zinc deficiency.

Zinc status and its requirement by rural adults consuming wheat from control or zinc-treated fields

Human zinc (Zn) deficiency is prevalent in areas where cereals dominate in the diet. Soil Zn application may enhance the concentration of Zn in wheat grains and dietary Zn intake by target populations. However, its value has never been practically quantified in Zn nutrition of any population group. We, therefore, studied farming families in rural Punjab (Pakistan). The selected adults (n = 156, grouped based on age and gender) were Zn undernourished (as assessed by estimated Zn bioavailability in their diet) and their plasma Zn levels also indicated Zn deficiency. On average, wheat consumption by the adults contributed about 68% in total Zn and 93% in total phytate intakes. Soil Zn application to wheat fields significantly increased Zn and decreased phytate concentration in chapati (flatbread made of whole-wheat flour). From dietary phytate intakes by the adults, we calculated desired chapati Zn concentration and dietary Zn intake that would meet their daily Zn requirement. The physiological Zn requirements of adult women and men were estimated to be achieved by intake of, respectively, 10.4-15.3 mg Zn d^-1 (37-46 mg Zn kg^-1 in chapati) and 14.4-23.3 mg Zn d^-1 (41-52 mg Zn kg^-1 in chapati). It was evident that soil Zn application aiming at optimum grain yield of wheat significantly improved Zn nutrition of the studied adults, but not up to desired levels. High Zn applications (via soil and/or foliage) to wheat and growing cultivars specifically selected for Zn biofortification may be needed to optimise Zn nutrition in rural Pakistan.

Zinc intake and status in Austria in the light of different reference values

Zinc has been identified as a critical micronutrient also in high-income countries. There is still some uncertainty about the evaluation of zinc sufficiency due to divergent daily intake reference values. We wanted to exemplify this issue using data from the Austrian Study on Nutritional Status 2012. Plasma zinc concentrations were measured in a nationally representative sample of 872 persons aged 6-80 years (55.5 % female). Dietary zinc intake was estimated from two 24h dietary recalls. Additionally, parameters of the antioxidative status (plasma malondialdehyde (MDA), total antioxidative capacity) and activities of alkaline phosphatase (AP), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px)) were determined. Zinc status was marginal in schoolchildren (40 % of boys and 22 % of girls) and in elderly (28 % of men and 33 % of women). Dietary zinc intake was also unsatisfactory in these groups with 38 % of boys and 32 % of girls and 64.5 % of older men below the nationally recommended intake levels. However, the adequacy of zinc intake varied with different reference values. Adults were more likely to meet the D-A-CH reference values and those from the European Food Safety Authority than the recommendations of the International Zinc Nutrition Consultative Group (IZiNCG) and the Institute of Medicine, whereas children met the IZiNCG values best. Zinc status correlated weakly with AP activity (r = -0.298, p < 0.001) and some antioxidant status markers (CAT, MDA, GSH-PX, SOD), especially in the elderly (MDA: r = -0.527, p < 0.001, and SOD: r = -0.466, p = 0.002). Our results suggest a suboptimal zinc supply in Austria particularly among schoolchildren and older adults.

A short 18 items food frequency questionnaire biochemically validated to estimate zinc status in humans

Inadequate dietary zinc intake is wide-spread in the world's population. Despite the clinical significance of zinc deficiency there is no established method or biomarker to reliably evaluate the zinc status. The aim of our study was to develop a biochemically validated questionnaire as a clinically useful tool that can predict the risk of an individual being zinc deficient. From 71 subjects aged 18-55 years blood and urine samples were collected. Zinc concentrations in serum and urine were determined by atomic absorption spectrometry. A food frequency questionnaire (FFQ) including 38 items was filled out representing the consumption during the last 6 months obtaining nutrient diet scores. Latter were calculated by multiplication of the particular frequency of consumption, the nutrient intake of the respective portion size and the extent of the consumed quantity. Results from the FFQ were compared with nutrient intake information gathered in 24-h dietary recalls. A hemogram was performed and cytokine concentrations were obtained using Enzyme-linked Immunosorbent Assay. Reducing the items of the primary FFQ from 38 to 18 did not result in a significant variance between both calculated scores. Zinc diet scores showed highly significant correlation with serum zinc (r = 0.37; p < 0.01) and urine zinc concentrations (r = 0.34; p < 0.01). Serum zinc concentrations and zinc diet scores showed a significant positive correlation with animal protein intake (r = 0.37; p < 0.01/r = 0.54; p < 0.0001). Higher zinc diet scores were found in omnivores compared to vegetarians (213.5 vs. 111.9; p < 0.0001). The 18 items FFQ seems to be a sufficient tool to provide a good estimation of the zinc status. Moreover, shortening of the questionnaire to 18 items without a loss of predictive efficiency enables a facilitated and resource-saving routine use. A validation of the questionnaire in other cohorts could enable the progression towards clinical utilization of this promising tool.

Serum Zinc Level and Eating Behaviors in Children Receiving Zinc Supplements without Physician Prescription

Background:

The aim of the study was to compare the serum zinc level and eating behaviors in 2–8-year-old children with and without arbitrarily zinc supplementation.

Materials and Methods:

This case–control study was conducted from December 2015 to December 2017 in Isfahan, Iran. The case group consisted of seventy children, aged 2–8 years, who have received zinc supplement without physician prescription; the controls were an equal number of age-matched children who did not receive any supplement. The serum zinc level was measured, and eating behaviors were identified using Children's Eating Behavior Questionnaire (CEBQ).

Results:

There was no significant difference in serum zinc level between two groups (P = 0.18). Some differences in CEBQ subscales were identified between the groups studied. In the control group, the subscale of enjoyment of food was higher than the case group (P < 0.001). In the case group, the subscales of food fussiness and satiety responsiveness were higher than controls (P < 0.001).

Conclusion:

In this study, serum zinc levels were not significantly different between the two groups, and arbitrarily zinc supplementation does not play an important role in improving anorexia subscales.

Perianal Lesions in Children: An Updated Review

Perianal lesions in children are common reasons for dermatology clinic visits and a well-defined approach to diagnosis and management is helpful to the practicing clinician. In this article, we review and update various etiologies of perianal lesions in the pediatric population, including infectious, papulosquamous, vascular, and neoplastic. We provide a standard initial approach to diagnosis and updates on current management. Infectious etiologies of perianal lesions discussed in this article include fungal, bacterial, parasitic, and viral. Perianal papulosquamous lesions often encountered in children, and discussed in this article, include acrodermatitis enteropathica, psoriasis, contact dermatitis, and many others. We also discuss the diagnosis and management of other entities including infantile hemangiomas, Langerhans cell histiocytosis, and fibrous hamartoma of infancy.

High Prevalence of Zinc Deficiency in Rural Nigerian Preschool Children: A Community-Based Cross-Sectional Study

Background and Aims: In Nigeria, community-based epidemiological data related to the prevalence of zinc deficiency in preschool children are scarce. We assessed the prevalence of zinc deficiency and the associated socio-demographic variables in children aged between 6 and 60 months, living in a Nigerian rural community.

Materials and Methods: In this cross-sectional study, the serum zinc concentrations of 252 children aged between 6 and 60 months in a rural community in Nigeria were assessed, using atomic absorption spectrophotometry. The study population was selected by multistage random sampling and at least two children were selected from every household which had children in the study age group. The socio-demographic characteristics of the subjects were obtained, using an interviewer-administered questionnaire.

Results: A total of 252 children were studied, 134 (53.2%) males and 118 (46.8%) females. The mean age was 32.7±17.0 months, similar for both sexes. Overall, 220 (87.3%) had low serum zinc concentrations (less than 7.65µmol/L). According to age, the highest mean serum zinc concentration was 5.43±3.52µmol/L in children aged between 6 and 12 months. Correlation between serum zinc concentration and family size or socio-economic status (SES) showed that the smaller the family size and the higher the SES, the higher the serum zinc concentration.

Conclusions: The high prevalence of low serum zinc concentration indicates that zinc deficiency is a public health problem in our rural communities, requiring public health intervention.

National Risk of Zinc Deficiency as Estimated by National Surveys

BACKGROUND

Information is needed on the national prevalence of zinc deficiency to guide program development and evaluation.

OBJECTIVE

To summarize results of national surveys that assessed plasma or serum zinc concentrations (PZC) and compare the prevalence of low PZC with other methods used to estimate countries' risk of zinc deficiency.

METHODS

National surveys that included PZC were identified through Internet searches and personal contacts. A survey was eligible if a nationally representative sampling scheme was used, PZC was analyzed, and the survey was implemented in a low- or middle-income country. Twenty surveys were eligible; 19 countries assessed PZC in young children and 14 in women of reproductive age.

RESULTS

In 13 of the 19 surveys, the prevalence of low PZC in children was >20%. Only Afghanistan, Azerbaijan, Nigeria, the Republic of Maldives, Sri Lanka, and China found a low prevalence of inadequate PZC among children. Some of these conclusions may be due to the lower than recommended cutoff that was used. Similarly, in 13 of 14 surveys, the prevalence of low PZC in women was >20%. Estimates of percentage population with inadequate dietary zinc intake based on food balance sheets underestimate the risk of zinc deficiency. The national stunting prevalence seems to be a useful proxy, as both indicators categorized countries similarly into high versus low risk of zinc deficiency, with some exceptions.

CONCLUSIONS

Results from 20 countries suggest that zinc deficiency is a public health concern in the majority of these countries and zinc intervention strategies should be considered.

Determination of zinc status in humans: which indicator should we use?

Zinc deficiency has serious wide-ranging health consequences and is thought to be one of the most prevalent micronutrient deficiencies in the world. However, reliable indicators or biomarkers to assess zinc status are not available at present. Indirect indicators such as the prevalence of stunting or anemia, iron deficiency, as well as more direct indicators such as plasma zinc concentrations are being used at present to estimate the prevalence of zinc deficiency in populations. However, as this paper shows by using data from a recent national micronutrient survey in Vietnam, the estimates of the prevalence of zinc deficiency using these different indicators can vary widely, leading to inconsistencies. In this paper, zinc deficiency among children is four times more prevalent than iron deficiency and 2.3 times more than stunting prevalence for example. This can lead not only to confusion concerning the real extent of the prevalence of zinc deficiency in populations, but also makes it hard to inform policy on whether action is needed or not. Moreover, evaluation of programs is hampered by the lack of a clear indicator. Efforts should be made to identify the most suitable indicator to evaluate the impact of programs aimed at improving zinc status and health of populations.

Biomarkers of Nutrition for Development (BOND)-Zinc Review

Zinc is required for multiple metabolic processes as a structural, regulatory, or catalytic ion. Cellular, tissue, and whole-body zinc homeostasis is tightly controlled to sustain metabolic functions over a wide range of zinc intakes, making it difficult to assess zinc insufficiency or excess. The BOND (Biomarkers of Nutrition for Development) Zinc Expert Panel recommends 3 measurements for estimating zinc status: dietary zinc intake, plasma zinc concentration (PZC), and height-for-age of growing infants and children. The amount of dietary zinc potentially available for absorption, which requires an estimate of dietary zinc and phytate, can be used to identify individuals and populations at risk of zinc deficiency. PZCs respond to severe dietary zinc restriction and to zinc supplementation; they also change with shifts in whole-body zinc balance and clinical signs of zinc deficiency. PZC cutoffs are available to identify individuals and populations at risk of zinc deficiency. However, there are limitations in using the PZC to assess zinc status. PZCs respond less to additional zinc provided in food than to a supplement administered between meals, there is considerable interindividual variability in PZCs with changes in dietary zinc, and PZCs are influenced by recent meal consumption, the time of day, inflammation, and certain drugs and hormones. Insufficient data are available on hair, urinary, nail, and blood cell zinc responses to changes in dietary zinc to recommend these biomarkers for assessing zinc status. Of the potential functional indicators of zinc, growth is the only one that is recommended. Because pharmacologic zinc doses are unlikely to enhance growth, a growth response to supplemental zinc is interpreted as indicating pre-existing zinc deficiency. Other functional indicators reviewed but not recommended for assessing zinc nutrition in clinical or field settings because of insufficient information are the activity or amounts of zinc-dependent enzymes and proteins and biomarkers of oxidative stress, inflammation, or DNA damage.