A Review of Dietary Zinc Recommendations

Background. Large discrepancies exist among the dietary zinc recommendations set by expert groups. Objective. To understand the basis for the differences in the dietary zinc recommendations set by the World Health Organization, the U.S. Institute of Medicine, the International Zinc Nutrition Consultative Group, and the European Food Safety Agency. Methods. We compared the sources of the data, the concepts, and methods used by the four expert groups to set the physiological requirements for absorbed zinc, the dietary zinc requirements (termed estimated and/or average requirements), recommended dietary allowances (or recommended nutrient intakes or population reference intakes), and tolerable upper intake levels for selected age, sex, and life-stage groups. Results. All four expert groups used the factorial approach to estimate the physiological requirements for zinc. These are based on the estimates of absorbed zinc required to offset all obligatory zinc losses plus any additional requirements for absorbed zinc for growth, pregnancy, or lactation. However, discrepancies exist in the reference body weights used, studies selected, approaches to estimate endogenous zinc losses, the adjustments applied to derive dietary zinc requirements that take into account zinc bioavailability in the habitual diets, number of dietary zinc recommendations set, and the nomenclature used to describe them. Conclusions. Estimates for the physiological and dietary requirements varied across the four expert groups. The European Food Safety Agency was the only expert group that set dietary zinc recommendations at four different levels of dietary phytate for adults (but not for children) and as yet no tolerable upper intake level for any life-stage group

Generating political commitment for ending malnutrition in all its forms: A system dynamics approach for strengthening nutrition actor networks.

Generating political commitment for ending all forms of malnutrition represents a key challenge for the global nutrition community. Without commitment, the policies, programs, and resources needed to improve nutrition are unlikely to be adopted, effectively implemented, nor sustained. One essential driver of commitment is nutrition actor network (NAN) effectiveness, the web of individuals and organizations operating within a given country who share a common interest in improving nutrition and who act collectively to do so. To inform new thinking and action towards strengthening NAN effectiveness, we use a systems dynamics theoretical approach and literature review to build initial causal loop diagrams (CLDs) of political commitment and NAN effectiveness and a qualitative group model building (GMB) method involving an expert workshop to strengthen model validity. First, a "nutrition commitment system" CLD demonstrates how five interrelated forms of commitment-rhetorical, institutional, operational, embedded, and system-wide-can dynamically reinforce or diminish one another over time. Second, we present CLDs demonstrating factors shaping NAN effectiveness organized into three categories: actor features, resources, and capacities; framing strategies, evidence, and norms; and institutional, political, and societal contexts. Together, these models generate hypotheses on how political commitment and NAN effectiveness could be strengthened in future and may provide potential starting points for country-specific conversations for doing so

Soil type influences crop mineral composition in Malawi

Food supply and composition data can be combined to estimate micronutrient intakes and deficiency risks among populations. These estimates can be improved by using local crop composition data that can capture environmental influences including soil type. This study aimed to provide spatially resolved crop composition data for Malawi, where information is currently limited. Six hundred and fifty-two plant samples, representing 97 edible food items, were sampled from N150 sites in Malawi between 2011 and 2013. Samples were analysed by ICP-MS for up to 58 elements, including the essential minerals calcium (Ca), copper (Cu), iron (Fe), magnesium (Mg), selenium (Se) and zinc (Zn). Maize grain Ca, Cu, Fe, Mg, Se and Zn concentrations were greater from plants grown on calcareous soils than those from the more widespread low-pH soils. Leafy vegetables from calcareous soils had elevated leaf Ca, Cu, Fe and Se concentrations, but lower Zn concentrations. Several foods were found to accumulate high levels of Se, including the leaves of Moringa, a crop not previously been reported in East African food composition data sets. New estimates of national dietary mineral supplies were obtained for non-calcareous and calcareous soils. High risks of Ca (100%), Se (100%) and Zn (57%) dietary deficiencies are likely on non-calcareous soils. Deficiency risks on calcareous soils are high for Ca (97%), but lower for Se (34%) and Zn (31%). Risks of Cu, Fe and Mg deficiencies appear to be low on the basis of dietary supply levels

Zinc Deficiency in Low and Middle Income Countries: Prevalence and Approaches for Mitigation

This review addresses the prevalence of zinc deficiency in Low and Middle Income Countries (LMICs) and assesses the available strategies for its alleviation. The paucity of national level data on the zinc deficiency in LMICs is partially due to the lack of a reliable biomarker. Zinc deficiency appears to be a public health problem in almost all the LMICs irrespective of the recommended indicators (plasma zinc concentration, dietary zinc adequacy and stunting prevalence) used. Based on plasma/serum zinc concentration (PZC), the most appropriate indicator at present, the prevalence of zinc deficiency in LMICs are of concern. Among the 25 countries for which national PZC data were available, 23 had a zinc deficiency prevalence of >20% for at least one physiological group. Zinc supplementation is largely restricted as an adjunct therapy for diarrhoea management in children, but the best platform and the most effective way of preventive zinc supplementation delivery needs to be determined. Impact assessment for current zinc fortification programmes in LMICs and the effectiveness of zinc supplementation as part of a multi-micronutrient powder is to be ascertained. Dietary diversification, though promising for LMICs, is in nascent stages of development at present. Inclusion of meat and animal products can be an important way to improve zinc status. Programmatic experience with the promotion of home processing techniques to increase absorbable zinc in the diet is lacking. Conventional biofortification techniques are gaining recognition in LMICs, however transgenic biofortification as a strategy remains controversial

Sex, gender, and health biotechnology: points to consider

<p>Abstract</p> <p>Background</p> <p>Reproductive technologies have been extensively debated in the literature. As well, feminist economists, environmentalists, and agriculturalists have generated substantial debate and literature on gender. However, the implications for women of health biotechnologies have received relatively less attention. Surprisingly, while gender based frameworks have been proposed in the context of public health policy, practice, health research, and epidemiological research, we could identify no systematic framework for gender analysis of health biotechnology in the developing world.</p> <p>Discussion</p> <p>We propose sex and gender considerations at five critical stages of health biotechnology research and development: priority setting; technology design; clinical trials; commercialization, and health services delivery.</p> <p>Summary</p> <p>Applying a systematic sex and gender framework to five key process stages of health biotechnology research and development could be a first step towards unlocking the opportunities of this promising science for women in the developing world.</p

Influence of psychological factors in food risk assessment - A review

Background: Typically, food-related risk assessments are carried out within a four step, technical framework, as detailed by the Codex Alimentarius Commission (World Health Organization/ Food and Agricultural Organization of the United Nations, 2015). However, the technical framework presumes a level of ‘objective risk’ and does not take into account that risk is complex and psychologically constructed, something which is rarely acknowledged within risk analysis as a whole. It is well documented that people's perceptions of risk are based on more than merely probability of occurrence, but reflect other non-technical psychological factors (e.g., risk origin, severity, controllability, familiarity). Moreover, the basis of these risk perceptions is largely similar for experts and non-experts. Scope and approach: In this review, we consider each stage of the risk assessment process from a psychological perspective, reviewing research on non-technical factors which could affect assessments of risk and subsequent risk management decisions, with a particular focus on food safety. Key Findings and Conclusions: We identify 12 factors from the psychological literature which could potentially influence how risks are assessed and characterised. Drawing on insights from this research, we propose a number of recommendations to standardise approaches in risk assessment. Acknowledging and working with the subjectivity of risk is key to ensuring the efficacy of the wider risk analysis process

Refinement of arsenic attributable health risks in rural Pakistan using population specific dietary intake values

Background: Previous risk assessment studies have often utilised generic consumption or intake values when evaluating ingestion exposure pathways. If these values do not accurately reflect the country or scenario in question, the resulting risk assessment will not provide a meaningful representation of cancer risks in that particular country/scenario. Objectives: This study sought to determine water and food intake parameters for one region in South Asia, rural Pakistan, and assess the role population specific intake parameters play in cancer risk assessment. Methods: A questionnaire was developed to collect data on sociodemographic features and 24-hour water and food consumption patterns from a rural community. The impact of dietary differences on cancer susceptibility linked to arsenic exposure was evaluated by calculating cancer risks using the data collected in the current study against standard water and food intake levels for the USA, Europe and Asia. A probabilistic cancer risk was performed for each set of intake values of this study. Results: Average daily total water intake based on drinking direct plain water and indirect water from food and beverages was found to be 3.5 L day-1 (95% CI: 3.38, 3.57) exceeding the US Environmental Protection Agency’s default (2.5 L day-1) and World Health Organization’s recommended intake value (2 L day-1). Average daily rice intake (469 g day-1) was found to be lower than in India and Bangladesh whereas wheat intake (402 g day−1) was higher than intake reported for USA, Europe and Asian sub-regions. Consequently, arsenic-associated cumulative cancer risks determined for daily water intake was found to be 17 in children of 3-6 years (95% CI: 0.0014, 0.0017), 14 in children of age 6-16 years (95% CI: 0.001, 0.0011) and 6 in adults of 16-67 years (95% CI: 0.0006, 0.0006) in a population size of 10000. This is higher than the risks estimated using the US Environmental Protection Agency and World Health Organization’s default recommended water intake levels. Rice intake data showed early life cumulative cancer risks of 15 in 10000 for children of 3-6 years (95% CI: 0.0012, 0.0015), 14 in children of 6-16 years (95% CI: 0.0011, 0.0014) and later life risk of 8 in adults (95% CI: 0.0008, 0.0008) in a population of 10000. This is lower than cancer risks in countries with higher rice intake and elevated arsenic levels (Bangladesh and India). Cumulative cancer risk from arsenic exposure showed the relative risk contribution from total water to be51%, from rice to be44% and wheat intake 5%. Conclusions: The study demonstrates the need to use population specific dietary information for risk assessment and risk management studies. Probabilistic risk assessment concluded the importance of dietary intake in estimating cancer risk, along with arsenic concentrations in water or food and age of exposed rural population

Urbanization and international trade and investment policies as determinants of noncommunicable diseases in Sub-Saharan Africa

There are three dominant globalization pathways affecting noncommunicable diseases in Sub-Saharan Africa (SSA): urbanization, trade liberalization, and investment liberalization. Urbanization carries potential health benefits due to improved access to an increased variety of food imports, although for the growing number of urban poor, this has often meant increased reliance on cheap, highly processed food commodities. Reduced barriers to trade have eased the importation of such commodities, while investment liberalization has increased corporate consolidation over global and domestic food chains. Higher profit margins on processed foods have promoted the creation of ‘obesogenic’ environments, which through progressively integrated global food systems have been increasingly ‘exported’ to developing nations. This article explores globalization processes, the food environment, and dietary health outcomes in SSA through the use of trend analyses and structural equation modelling. The findings are considered in the context of global barriers and facilitators for healthy public policy.Department of HE and Training approved lis

Invited commentary to the paper ‘Zinc status and its association with the health of adolescents: a review of studies in India’

We are pleased to view the article based on Dr. Rama Kawade's thesis illustrating the importance of micronutrient adequacy, especially zinc, and associated health implications in Indian adolescent girls. This brief commentary addresses three major aspects in which Kawade's work has made a significant contribution; nutrition and health issues of adolescents, rising importance of zinc in terms of deficiency problems being addressed, and development of dietary interventions to alleviate micronutrient deficiencies