Household food security and dietary diversity in south-eastern Nigeria.

The aim of this study was to investigate household food security (access) level and the dietary diversity of households in the Nsukka Local Government Area in South-eastern Nigeria. From 20 local communities of Nsukka, 390 women were randomly sampled from the women's group and asked to complete a survey that determined the Household Food Insecurity Access Scale scores and the Household Dietary Diversity Scores (HDDS). The descriptive results indicated a high level of food insecurity with 82.6% households reporting various degrees of food insecurity. Over half of the sampled population experienced insufficient food quality. They either ate unwanted food (65.9%), limited variety (63.1%), or unpreferred food (64.6%). Some households experienced insufficient food intake by going a whole day without food (38.2%), go to sleep hungry (45.1%), or have no food of any kind (49%). The analysis of variance showed no significant difference (p = 0.428) in the food security level of households headed by males as compared with those headed by females. Approximately 53.6% of households fell at or below the average HDDS; males headed 48% of these households, while females headed 64%. The chi-square test indicated factors associated with household food security including age, education, work status and income, whereas the gender of the household head, household size and marital status were not significantly associated. Public-private partnerships, nutrition orientation and food intervention programs could improve food security in this area.

Report of the International Society for Zinc Biology 5th Meeting, in Collaboration with Zinc-Net (COST Action TD1304)-UCLan Campus, Pyla, Cyprus.

From 18 to 22 June 2017, the fifth biennial meeting of the International Society for Zinc Biology was held in conjunction with the final dissemination meeting of the Network for the Biology of Zinc (Zinc-Net) at the University of Central Lancashire, Cyprus campus. The meeting attracted over 160 participants, had 17 scientific symposia, 4 plenary speakers and 2 poster discussion sessions. In this report, we give an overview of the key themes of the meeting and some of the highlights from the scientific programme.

Assessing zinc in humans.

PURPOSE OF REVIEW: To examine the most recent literature that provides new data regarding the potential and emerging biomarkers for zinc status in individuals. RECENT FINDINGS: Suboptimal dietary zinc intake is estimated to affect 17% of the world's population; however, the assessment of zinc status is notoriously difficult. A systematic review and meta-analysis of studies investigating biochemical biomarkers of zinc status was conducted by the European Micronutrient Recommendations Aligned network. This review summarized the data published from inception to 2007. More recently (2016), an international expert panel, convened by the biomarker of nutrition for development initiative, published an extensive review of the literature addressing biomarkers of zinc status in populations and individuals and categorized the biomarkers as useful [dietary intake, serum Zn concentration and stunting], potentially useful [hair Zn concentration, urine Zn concentration and neurobehavioural function] and emerging [nail Zn concentration, oxidative stress and DNA integrity, zinc kinetics, zinc-dependent proteins and taste acuity]. SUMMARY: The most recent data on the potentially useful biomarkers support the further investigation of hair Zn concentration and indices of neurological function, particularly those assessing memory and attention. Of the emerging biomarkers, the measurement of DNA integrity and the expression of zinc transport proteins look promising.

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.

Preventing and Controlling Zinc Deficiency Across the Life Course: A Call to Action.

Through diverse roles, zinc determines a greater number of critical life functions than any other single micronutrient. Beyond the well-recognized importance of zinc for child growth and resistance to infections, zinc has numerous specific roles covering the regulation of glucose metabolism, and growing evidence links zinc deficiency with increased risk of diabetes and cardiometabolic disorders. Zinc nutriture is, thus, vitally important to health across the life course. Zinc deficiency is also one of the most common forms of micronutrient malnutrition globally. A clearer estimate of the burden of health disparity attributable to zinc deficiency in adulthood and later life emerges when accounting for its contribution to global elevated fasting blood glucose and related noncommunicable diseases (NCDs). Yet progress attenuating its prevalence has been limited due, in part, to the lack of sensitive and specific methods to assess human zinc status. This narrative review covers recent developments in our understanding of zinc's role in health, the impact of the changing climate and global context on zinc intake, novel functional biomarkers showing promise for monitoring population-level interventions, and solutions for improving population zinc intake. It aims to spur on implementation of evidence-based interventions for preventing and controlling zinc deficiency across the life course. Increasing zinc intake and combating global zinc deficiency requires context-specific strategies and a combination of complementary, evidence-based interventions, including supplementation, food fortification, and food and agricultural solutions such as biofortification, alongside efforts to improve zinc bioavailability. Enhancing dietary zinc content and bioavailability through zinc biofortification is an inclusive nutrition solution that can benefit the most vulnerable individuals and populations affected by inadequate diets to the greatest extent.

Methods of Assessment of Zinc Status in Humans: An Updated Review and Meta-analysis.

CONTEXT: The assessment of zinc status is difficult but essential for the identification of zinc deficiency and evaluation of interventions to improve zinc status. OBJECTIVE: The purpose of this systematic review (SR) and meta-analysis was to update the previously published SR of biomarkers of zinc status, conducted by the European Micronutrient Recommendations Aligned (EURRECA) network in 2009, to answer the question: Which putative measures (biomarkers) of zinc status appropriately reflect a change in zinc intake of at least 2 weeks? DATA SOURCES: A structured search strategy was used to identify articles published between January 2007 and September 2022 from MEDLINE (Ovid), Embase (Ovid), Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials (CENTRAL). Relevant articles were identified using previously defined eligibility criteria. DATA EXTRACTION: Data were extracted and combined with data from the previous SR. DATA ANALYSIS: A random-effects model was used to calculate pooled mean differences using STATA (StataCorp). The risk of bias and the certainty of evidence for all outcomes were assessed. Additional data on 7 of the 32 previously reported biomarkers were identified, along with data on an additional 40 putative biomarkers from studies published since 2007. Pooled data analysis confirmed that, in healthy participants, both plasma/serum zinc concentration and urinary zinc excretion responded to changes in zinc intake (plasma/serum: mean effect [95% CI], controlled studies: 2.17 µmol/L [1.73, 2.61]; P < .005, I2 = 97.8; before-and-after studies: 2.87 µmol/L [2.45, 3.30]; P < .005, I2 = 98.1%; urine zinc: 0.39 mmol/mol creatinine [0.17, 0.62]; P < .005, I2 = 81.2; 3.09 µmol/day [0.16, 6.02]; P = .039, I2 = 94.3). CONCLUSION: The updated analyses support the conclusion that plasma/serum and urinary zinc respond to changes in zinc intake in studies of healthy participants. Several additional putative biomarkers were identified, but more studies are needed to assess the sensitivity and reliability. SYSTEMATIC REVIEW REGISTRATION: PROSPERO no. CRD42020219843.

EURRECA-Estimating zinc requirements for deriving dietary reference values.

Zinc was selected as a priority micronutrient for EURRECA, because there is significant heterogeneity in the Dietary Reference Values (DRVs) across Europe. In addition, the prevalence of inadequate zinc intakes was thought to be high among all population groups worldwide, and the public health concern is considerable. In accordance with the EURRECA consortium principles and protocols, a series of literature reviews were undertaken in order to develop best practice guidelines for assessing dietary zinc intake and zinc status. These were incorporated into subsequent literature search strategies and protocols for studies investigating the relationships between zinc intake, status and health, as well as studies relating to the factorial approach (including bioavailability) for setting dietary recommendations. EMBASE (Ovid), Cochrane Library CENTRAL, and MEDLINE (Ovid) databases were searched for studies published up to February 2010 and collated into a series of Endnote databases that are available for the use of future DRV panels. Meta-analyses of data extracted from these publications were performed where possible in order to address specific questions relating to factors affecting dietary recommendations. This review has highlighted the need for more high quality studies to address gaps in current knowledge, in particular the continued search for a reliable biomarker of zinc status and the influence of genetic polymorphisms on individual dietary requirements. In addition, there is a need to further develop models of the effect of dietary inhibitors of zinc absorption and their impact on population dietary zinc requirements.

Effect of zinc intake on mental and motor development in infants: a meta-analysis.

A systematic review and meta-analysis of available randomized controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on mental and motor development in infants. Out of 5500 studies identified through electronic searches and reference lists, 5 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on mental and motor development was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional situation, and risk of bias. Indices of mental and motor development assessed were the Mental Development Index (MDI) and Psychomotor Development Index (PDI). Additionally we carried out a sensitivity analysis. The pooled ß was -0.01 (95 %CI -0.02, 0) for MDI and 0 (95 %CI -0.03, 0.02) for PDI, with a substantial heterogeneity in both analyses. When we performed a meta-regression, the effect of Zn supplementation on MDI changed depending on the dose of supplementation. Regarding PDI, there was a differential effect of Zn intake depending on intervention duration, dose of supplementation, nutritional situation, and risk of bias. Zn supplementation showed a negative, weak and significant effect on PDI score in those studies with a length of 4 to 20 weeks (ß= -0.05; CI 95 % -0.06 to -0.04). In conclusion, no association was found between Zn intake and mental and motor development in infants. Further standardized research is urgently needed to clarify the role of Zn supplementation upon infant mental and motor development, particularly in Europe.

Effect of zinc intake on serum/plasma zinc status in infants: a meta-analysis.

A systematic review and meta-analysis of available randomised controlled trials (RCTs) was conducted to evaluate the effect of zinc (Zn) intake on serum/plasma Zn status in infants. Out of 5500 studies identified through electronic searches and reference lists, 13 RCTs were selected after applying the exclusion/inclusion criteria. The influence of Zn intake on serum/plasma Zn concentration was considered in the overall meta-analysis. Other variables were also taken into account as possible effect modifiers: doses of Zn intake, intervention duration, nutritional status and risk of bias. The pooled ß of status was 0.09 [confidence interval (CI) 0.05 to 0.12]. However, a substantial heterogeneity was present in the analyses (I(2) = 98%; P = 0.00001). When we performed a meta-regression, the effect of Zn intake on serum/plasma Zn status changed depending on the duration of the intervention, the dose of supplementation and the nutritional situation (P ANCOVA = 0.054; <0.001 and <0.007, respectively). After stratifying the sample according to the effect modifiers, the results by duration of intervention showed a positive effect when Zn intake was provided during medium and long periods of time (4-20 weeks and >20 weeks). A positive effect was also seen when doses ranged from 8.1 to 12 mg day(-1). In all cases, the pooled ß showed high evidence of heterogeneity. Zn supplementation increases serum/plasma Zn status in infants, although high evidence of heterogeneity was found. Further standardised research is urgently needed to reach evidence-based conclusions to clarify the role of Zn supplementation upon infant serum/plasma Zn status, particularly in Europe.

Effects of a Nutrition Education Programme in Stage IV Cardiac Rehabilitation Patients: A 3-Arm Randomised Controlled Trial.

This trial examined the influence of two nutrition intervention programmes on health-related and nutritional intake indices pertinent to cardiovascular disease compared to usual care in stage IV cardiac rehabilitation patients. Sixty-six patients were recruited from the Heartbeat North-West cardiac rehabilitation centre in Preston (United Kingdom). Patients were randomly assigned to Usual care, Biggest loser or Nutrition education arms. Usual care undertook their usual two exercise classes per week without nutritional support, Biggest loser underwent weekly education sessions focussing on weight loss using the themes within the British Heart Foundation 'So You Want to Lose Weight for Good' guidelines, and Nutrition education followed the same themes as Biggest loser but in a more focussed manner informed by patient focus groups. In total, this was a 12-week trial in which patients spent 6 weeks engaged in their allocated intervention arm, after which all participants switched to Usual care. The primary outcome was systolic blood pressure, and secondary measures of anthropometric, blood biomarker, nutritional knowledge (via the Mediterranean Diet Assessment Tool) and nutritional intake indices were measured at baseline, 6 weeks, and 12 weeks (follow-up). Intention-to-treat analyses revealed no significant alterations in the primary outcome (Usual care: baseline = 130.45 mmHg, 6 weeks = 127.83 mmHg, and follow-up = 126.35 mmHg, Biggest loser: baseline = 133.50 mmHg, 6 weeks = 123.06 mmHg, and follow-up = 135.22 mmHg, or Nutrition education: baseline = 135.23 mmHg, 6 weeks = 129.20 mmHg, and follow-up = 126.26 mmHg) between arms. However, at 6 weeks, improvements in triglycerides were significantly greater in Usual care (baseline = 1.61 mmol/L and 6 weeks = 1.43 mmol/L) group compared to Nutrition education (baseline = 1.70 mmol/L and 6 weeks = 2.21 mmol/L). Improvements in nutrition knowledge were significantly greater in Nutrition education (baseline = 8.48, 6 weeks = 9.77, and follow-up = 10.07) compared to Usual care (baseline = 7.71, 6 weeks = 8.00, and follow-up = 8.00) and Biggest loser (baseline = 7.71, 6 weeks = 8.73, and follow-up = 8.36). At 6 weeks, the Biggest loser group (baseline = 4.75 g and 6 weeks = 3.83 g) exhibited significantly greater improvements in salt intake compared to Usual care (baseline = 4.87 g and 6 weeks = 4.28 g) and Nutrition education (baseline = 19.25 g and 6 weeks = 16.78 g) in saturated fatty acids compared to Usual care (baseline = 20.26 g and 6 weeks = 21.34 g). This trial shows the effectiveness of nutritional interventions for improving nutritional knowledge and dietary practices in stage IV cardiac rehabilitation, but the mechanisms and longer-term effects of increased triglyceride levels in the Nutrition education group requires further exploration.

School Feeding to Improve Cognitive Performance in Disadvantaged Children: A 3-Arm Parallel Controlled Trial in Northwest Pakistan.

Malnutrition is associated with reduced learning aptitude and growth during childhood. We examined the impact of providing two school lunch variants, a standard school meal (school feeding, n = 70), or the standard meal with additional micronutrients (school feeding + micronutrient powder (MNP), n = 70), in children attending two schools in northwest Pakistan. A third local government school, where no lunch was provided (no school feeding, n = 70), served as the control. The primary outcome, cognitive function, was assessed using the Raven's Coloured Progressive Matrices (RCPM) test, alongside haemoglobin, at three-time points: T1 (baseline, before the initiation of the school lunch programme), T2 and T3 (5 and 12 months, respectively, after the introduction of the school lunch). Data were analysed using linear mixed-effects models to contrast between trial groups, the changes from T1 to T2 and T3. Adjusted for T1 and other co-variates, improvements in the RCPM scores were significantly greater in the school feeding group at T2 (b = 1.61, (95% CI = 0.71-2.52), t = 3.52, p = 0.001) and T3 (b = 1.28, (95% CI = 0.22-2.35), t = 2.38, p = 0.019) compared with no school feeding. In addition, at T2 (b = 1.63, (95% CI = -0.10-3.37), t = 1.86, p = 0.065), there were no significant differences between school feeding + MNP and no school feeding groups. However, improvements in the RCPM scores were significantly greater in the school feeding + MNP group at T3 (b = 2.35, (95% CI = 0.51-4.20), t = 2.53, p = 0.013) compared with no school feeding. The findings indicate an improvement in cognitive performance in children who received a school meal with and without MNP, over a 12-month period. Currently there is no operational school feeding programme at the national or provincial level in Pakistan. Our findings, therefore, highlight the need for school feeding programmes to improve learning opportunities for children from underprivileged communities.

Toward revising dietary zinc recommendations for children aged 0 to 3 years: a systematic review and meta-analysis of zinc absorption, excretion, and requirements for growth.

CONTEXT: The Food and Agriculture Organization of the United Nations and the World Health Organization are updating their dietary zinc recommendations for children aged 0 to 3 years. OBJECTIVE: The aim of this review was to retrieve and synthesize evidence regarding zinc needs for growth as well as zinc losses, absorption, and bioavailability from the diet. DATA SOURCES: MEDLINE, Embase, and Cochrane Library databases were searched electronically from inception to August 2020. Studies assessing the above factors in healthy children aged 0 to 9 years were included, with no limits on study design or language. DATA EXTRACTION: Ninety-four studies reporting on zinc content in tissue (n = 27); zinc absorption (n = 47); factors affecting zinc bioavailability (n = 30); and endogenous zinc losses via urine, feces, or integument (n = 40) met the inclusion criteria. Four reviewers extracted data and two reviewers checked for accuracy. DATA ANALYSES: Studies were synthesized narratively, and meta-analyses of zinc losses and gains as well the subgroups of age, type of feeding, country's income, and molar ratio of phytate to zinc were conducted. Meta-analysis revealed an overall mean (95%CI) urinary and endogenous fecal zinc excretion of 17.48 µg/kg/d (11.80-23.15; I2 = 94%) and 0.07 mg/kg/d (0.06-0.08; I2 = 82%), respectively, with a mean fractional zinc absorption of 26.75% (23.69-29.81; I2 = 99%). Subgrouping by age revealed differences in mean values associated with the transition from milk-based diets to solid food during the first 3 years of life. CONCLUSION: This review synthesizes data that may be used to formulate zinc requirements in young children. Results should be interpreted with caution because of considerable heterogeneity in the evidence. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42020215236.

Effectiveness of locally produced ready to use supplementary food on hemoglobin, anthropometrics, and plasma micronutrients concentrations of 6 to 23 months age children: a non-randomized community-based trial from Pakistan.

Background: Micronutrient deficiencies including vitamin A, vitamin D, and zinc are highly prevalent in children below 5 years of age in low and -middle-income countries. We aimed to evaluate the effectiveness of ready-to-use Lipid-based Nutrient Supplement-Medium Quantity (LNS-MQ) local name "Wawa-mum" on plasma micronutrient status, hemoglobin concentration and anthropometric measurements. Methods: A community-based non-randomized trial was conducted in the Kurram district of Khyber Pakhtunkhwa from January 2018 to June 2019. A total of 110 children aged 6 to 23 months old were recruited and allocated to the intervention and control arm of the study. A total of 57 children in the intervention arm received a daily ration of 50 g of Wawa-mum, for one year. To assess the impact of the intervention on primary outcome measures, i.e., serum vitamin A, D concentration, plasma zinc, and hemoglobin concentration. Blood samples were collected at baseline and after one year following the intervention. The vitamins concentration in serum were assessed using Enzyme-Linked Immunosorbent Assay (ELISA) and plasma zinc by atomic absorption spectrometry. The hemoglobin concentration was measured by an automated hematology analyzer. A 24-h dietary recall interview was used to assess the nutrient intake adequacy. Multivariate Linear regression models were used to analyze the outcomes while controlling for potential confounders. Results: In the intervention arm, children had on average 6.2 µg/dL (95% CI 3.0-9.3, value of p<0.001) increase in the serum vitamin A concentration, 8.1 ng/mL (95% CI 1.3-14.9, value of p 0.02) increase in serum vitamin D concentration and 49.0 µg/dL (95% CI 33.5-64.5, value of p<0.001) increase in the plasma zinc concentration, and 2.7 g/dL (95% CI 2.0-3.3, value of p<0.001) increase in hemoglobin concentration while adjusted for covariates. An addition, length-for-age z-score (LAZ), weight-for-length z-score (WLZ), weight-for-age z-score (WAZ), and prevalence of undernutrition including stunting, wasting, and underweight were calculated as a secondary outcome to investigate the impact of micronutrients on growth parameters, that has been improved significantly after receiving the Wawa-mum. Conclusion: Wawa-mum (LNS-MQ) is an effective intervention to improve the micronutrient status, hemoglobin concentration, and growth parameters in 6 to 23 months children, which can be scaled up in the existing health system to address the alarming rates of under nutrition in Pakistan and other developing countries. Clinical trial registration: https://doi.org/10.1186/ISRCTN94319790, ISRCTN94319790.

Farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan: a mixed methods study.

Background: Zinc biofortified wheat may be a sustainable strategy to increase zinc intake in areas where fortification and dietary diversification are not feasible or are limited by household purchasing power. This convergent mixed methods study aimed to explore the farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan. Methods: A telephone survey was conducted with farmers (n = 418) who were provided with Zincol-2016 biofortified wheat seed for the 2019-2020 growing season, as part of a wheat grain micronutrient mapping study across Punjab Province. The survey explored the farmers' experiences of growing Zincol-2016 and whether they opted to grow it again in the subsequent season. Semi-structured focus group discussions were undertaken in a separate group of farmers in Khyber Pakhtunkhwa (KP) province (n = 12) who grew Zincol-2016 for the BiZiFED2 RCT. Millers were also interviewed in KP, both those who had processed Zincol-2016 for the trial (n = 12) and those who had no experience of processing biofortified wheat (n = 12). Survey data were analyzed using descriptive statistics and transcripts of focus groups were analyzed using thematic analysis. Results: Nearly half of farmers who responded to the survey (47%) re-cultivated Zincol-2016 in the following season. The drivers for Zincol-2016 re-cultivation were seed availability (100%), grain yield and growth resistance (98%), quality of the flour from the previous harvest (97%) and nutritional benefit (94.5%). Discussions with farmers suggested that the main motivators for potential scale-up of biofortified wheat were the perceived quality of the grain, wheat, and flour. Millers saw it as an opportunity to expand their business. Farmers and millers valued the health benefits of the wheat. Challenges for scale-up include the need of additional support to produce it, unfamiliarity with the biofortification process, production costs, and external threats to the supply chain. Conclusion: Farmers and millers showed a strong implicit preference for Zincol-2016 over alternative varieties. Crop performance and product yield were the most cited motivators for growing Zincol-2016. Farmers and millers are willing to produce and process biofortified wheat if financial and educational support is provided.

Single hair analysis by X-ray fluorescence spectrometry detects small changes in dietary zinc intake: A nested randomized controlled trial.

The aim of this study was to determine whether X-ray fluorescence spectrometry (XRF) could be used to detect changes in hair zinc concentration in response to a modest daily increase in zinc from the consumption of zinc biofortified wheat flour. This study was conducted as part of an effectiveness trial (BiZiFED2) exploring the potential for zinc biofortified wheat to alleviate zinc deficiency in adolescent girls aged 10-16 years in Pakistan (trial registration ID ISRCTN17107812). A randomized controlled design was used. Participants received either control flour or zinc biofortified flour for 6 months. Consumption of biofortified flour resulted in an average daily increase in dietary zinc intake of 1.5 mg per day above that of the control flour. At baseline and at the end of the intervention, individual hair samples (control: n = 59, intervention: n = 64) were analyzed for zinc and sulfur content by XRF. Data were analyzed using linear mixed effects models to contrast between trial groups the changes from baseline to end point and also to compare baseline and end point values within each trial group. Increases from baseline to endpoint in both sulfur and zinc were significantly greater in the intervention group compared to control (sulfur counts. CONTROL: baseline = 119.87 ± 20.33 and endpoint = 121.58 ± 23.58/intervention: baseline = 122.67 ± 24.19 and endpoint = 131.60 ± 21.34); (Zinc counts. CONTROL: baseline = 50.88 ± 14.33 and endpoint = 54.82 ± 14.61/intervention: baseline = 49.61 ± 10.77 and endpoint = 58.79 ± 12.20). For these parameters, there were also significant increases from baseline to endpoint in the intervention group but not in control. Furthermore, for Zn:S count ratio there were no differences in terms of the magnitude of the change from baseline to endpoint in the control group, although significant increases from baseline to endpoint were evident in the intervention group (Zn:S count ratio. CONTROL: baseline = 0.42 ± 0.10 and endpoint = 0.45 ± 0.08/intervention: baseline = 0.41 ± 0.08 and endpoint = 0.45 ± 0.08). A modest increase in dietary zinc over 6 months resulted in a detectable increase in both sulfur and zinc counts in individual hairs measured using XRF. This offers a sensitive, non-invasive method to monitor changes within subjects in response to dietary zinc interventions.

The relationship between zinc intake and serum/plasma zinc concentration in adults: a systematic review and dose-response meta-analysis by the EURRECA Network.

Dietary Zn recommendations vary widely across Europe due to the heterogeneity of approaches used by expert panels. Under the EURopean micronutrient RECommendations Aligned (EURRECA) consortium a protocol was designed to systematically review and undertake meta-analyses of research data to create a database that includes 'best practice' guidelines which can be used as a resource by future panels when setting micronutrient recommendations. As part of this process, the objective of the present study was to undertake a systematic review and meta-analysis of previously published data describing the relationship between Zn intake and status in adults. Searches were performed of literature published up to February 2010 using MEDLINE, Embase and the Cochrane Library. Data extracted included population characteristics, dose of Zn, duration of study, dietary intake of Zn, and mean concentration of Zn in plasma or serum at the end of the intervention period. An intake-status regression coefficient (ß ) was estimated for each individual study, and pooled meta-analysis undertaken. The overall pooled ß for Zn supplementation on serum/plasma Zn concentrations from randomised controlled trials and observational studies was 0·08 (95 % CI 0·05, 0·11; P < 0·0001; I² 84·5 %). An overall ß of 0·08 means that for every doubling in Zn intake, the difference in Zn serum or plasma concentration is ß (2(0·08) = 1·06), which is 6 %. Whether the dose-response relationship, as provided in the present paper, could be used as either qualitative or quantitative evidence to substantiate the daily Zn intake dose necessary to achieve normal or optimal levels of biomarkers for Zn status remains a matter of discussion.

Development and implementation of a nutrition intervention programme in North West Pakistan: a realist framework.

Maternal and infant malnutrition is prevalent in rural regions of NW Pakistan. This article reports on the use of a combination of a realist Context-Mechanism-Outcome framework and participatory appraisal methods to facilitate the development of a locally sensitive and responsive nutritional intervention programme. Data were gathered through a series of focus group (FG) discussions with local lady health workers, as well as pregnant and breastfeeding women attending an Emergency Field Hospital in North West Pakistan between May 2008 and March 2009. A nutrition intervention programme was implemented that involved cookery demonstration kitchens and free food supplements, coupled with nutrition and healthcare information and advice for pregnant and breastfeeding women. Subsequent FG discussions revealed that the programme had a positive impact on knowledge gained by women in the community and generated an openness to receiving and spreading knowledge. The framework, which rested on the use of a double feedback loop, involving local women, lady health workers, local researchers and UK-based researchers, has enabled not only the establishment of the programme, but has also given the local team the tools to apply for, and gain, further funding for the development of nutrition support services. The development of such methodological tools, which empower local researchers and service providers (wherever located) to operationalize local knowledge and assess interventions, is particularly relevant in international financially-constrained contexts.

The potential of spot urine as a biomarker for zinc assessment in Malawian children and adults.

Population-level assessment of zinc deficiency remains a challenge due to the lack of suitable biomarkers. Spot urinary zinc concentration (UZC) has the potential to provide information on population zinc status in large-scale surveys, but there is no established cut-off point indicating deficiency. A strong correlation between this biomarker and an established biomarker such as serum zinc concentration (SZC) in paired samples (i.e., from the same individual), could identify the thresholds indicating zinc deficiency. This study, therefore, aimed to regress spot UZC from school-aged children and women from the Malawi micronutrient survey with paired SZC data using a linear mixed-effects model. The nested variance components indicated no linear relationship between the UZC and SZC data, irrespective of adjustments for inflammation and hydration. Thresholds of urinary zinc excretion that have been suggested by expert panels were applied to the spot UZC data, as a post-hoc analysis. The zinc deficiency prevalence estimates derived from these suggested thresholds were not similar to the estimates from the SZC data, and further research is required to understand whether spot UZC can still provide useful information in population zinc assessment.

Community Perceptions of Zinc Biofortified Flour during an Intervention Study in Pakistan.

Zinc-biofortified flour may be a cost-effective approach to improve zinc status of populations in low-resource settings. The success of biofortification programmes is subject to acceptability and uptake by consumers. This study explored community leaders' and community members' (n = 72) experiences and attitudes towards the flour provided during a cluster randomised controlled trial of zinc biofortified wheat in rural Pakistan (BiZiFED2). Focus group discussions (n = 12) were conducted and thematic analysis applied using an inductive, semantic, contextualist approach. Five themes were identified: (1) Contribution to food security; (2) Better sensory and baking properties than local flour; (3) Perceived health benefits; (4) Willingness to pay for the flour; and (5) Importance of trusted promoters/suppliers. Although the participants were blind to whether they had received control or biofortified flour, referred to collectively as "study flour", the results indicated that the study flour performed well in terms of its taste and bread making qualities, with no adverse reports from participants in either arm of the BIZIFED2 RCT. Participants suggested that they would buy the biofortified wheat if this was available at a fair price due to perceived health benefits, reporting positive sensory characteristics and cooking attributes when compared to the flour available in the local markets. Overall, there was a positive reception of the programme and flour among the participants, and members of the community hoped for its continuation and expansion.

Adverse Effects of Excessive Zinc Intake in Infants and Children Aged 0-3 Years: A Systematic Review and Meta-Analysis.

Zinc supplementation reduces morbidity, but evidence suggests that excessive intakes can have negative health consequences. Current guidelines of upper limits (ULs) of zinc intake for young children are extrapolated from adult data. This systematic review (PROSPERO; registration no. CRD42020215187) aimed to determine the levels of zinc intake at which adverse effects are observed in young children. Studies reporting potential adverse effects of zinc intake in children aged 0-3 y were identified (from inception to August 2020) in MEDLINE, Embase, and the Cochrane Library, with no limits on study design. Adverse clinical and physical effects of zinc intake were synthesized narratively, and meta-analyses of biochemical outcomes were conducted. Random effects models were used to generate forest plots to examine the evidence by age category, dose, dose duration, chemical formula of zinc, and zinc compared with placebo. The Joanna Briggs Institute Critical Appraisal Checklist, Cochrane Risk of Bias 2, and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) guideline were employed to assess risk of bias and to appraise the certainty of evidence. Fifty-eight studies assessed possible adverse effects of zinc doses ranging from 3 to 70 mg/d. Data from 39 studies contributed to meta-analyses. Zinc supplementation had an adverse effect on serum ferritin, plasma/serum copper concentration, serum transferrin receptor, hemoglobin, hematocrit, and the odds of anemia in ≥1 of the subgroups investigated. Lactulose:mannitol ratio was improved with zinc supplementation, and no significant effect was observed on C-reactive protein, erythrocyte superoxide dismutase, zinc protoporphyrin, blood cholesterol, and iron deficiency anemia. The certainty of the evidence, as assessed using GRADE, was very low to moderate. Although possible adverse effects of zinc supplementation were observed in some subgroups, it is unclear whether these findings are clinically important. The synthesized data can be used to undertake a dose-response analysis to update current guidelines of ULs of zinc intake for young children.