Ian Darnton-Hill

A global response to a global problem: the epidemic of overnutrition

It is estimated that by 2020 two-thirds of the global burden of disease will be attributable to chronic noncommunicable diseases, most of them strongly associated with diet. The nutrition transition towards refined foods, foods of animal origin, and increased fats plays a major role in the current global epidemics of obesity, diabetes and cardiovascular diseases, among other noncommunicable conditions. Sedentary lifestyles and the use of tobacco are also significant risk factors. The epidemics cannot be ended simply by encouraging people to reduce their risk factors and adopt healthier lifestyles, although such encouragement is undoubtedly beneficial if the targeted people can respond. Unfortunately, increasingly obesogenic environments, reinforced by many of the cultural changes associated with globalization, make even the adoption of healthy lifestyles, especially by children and adolescents, more and more difficult. The present paper examines some possible mechanisms for, and WHOs role in, the development of a coordinated global strategy on diet, physical activity and health. The situation presents many countries with unmanageable costs. At the same time there are often continuing problems of undernutrition. A concerted multisectoral approach, involving the use of policy, education and trade mechanisms, is necessary to address these matters.

Maternal and child undernutrition: effective action at national level

80% of the worlds undernourished children live in just 20 countries. Intensified nutrition action in these countries can lead to achievement of the first Millennium Development Goal (MDG) and greatly increase the chances of achieving goals for child and maternal mortality (MDGs 4 and 5). Despite isolated successes in specific countries or for interventions--eg, iodised salt and vitamin A supplementation--most countries with high rates of undernutrition are failing to reach undernourished mothers and children with effective interventions supported by appropriate policies. This paper reports on an assessment of actions addressing undernutrition in the countries with the highest burden of undernutrition, drawing on systematic reviews and best-practice reports. Seven key challenges for addressing undernutrition at national level are defined and reported on: getting nutrition on the list of priorities, and keeping it there; doing the right things; not doing the wrong things; acting at scale; reaching those in need; data-based decisionmaking; and building strategic and operational capacity. Interventions with proven effectiveness that are selected by countries should be rapidly implemented at scale. The period from pregnancy to 24 months of age is a crucial window of opportunity for reducing undernutrition and its adverse effects. Programme efforts, as well as monitoring and assessment, should focus on this segment of the continuum of care. Nutrition resources should not be used to support actions unlikely to be effective in the context of country or local realities. Nutrition resources should not be used to support actions that have not been proven to have a direct effect on undernutrition, such as stand-alone growth monitoring or school feeding programmes. In addition to health and nutrition interventions, economic and social policies addressing poverty, trade, and agriculture that have been associated with rapid improvements in nutritional status should be implemented. There is a reservoir of important experience and expertise in individual countries about how to build commitment, develop and monitor nutrition programmes, move toward acting at scale, reform or phase-out ineffective programmes, and other challenges. This resource needs to be formalised, shared, and used as the basis for setting priorities in problem-solving research for nutrition.

Vitamin A Deficiency

Vitamin A deficiency affects an estimated 190 million preschool-aged children and 10 million pregnant women in low-income countries. Prevalent cases of xerophthalmia in young children are believed to number ~5 million. Of these, 10% can be considered potentially blinding, such that this ocular condition remains the leading cause of preventable pediatric blindness in the developing world. Although there has been a significant decrease in the prevalence of vitamin A deficiency during the past couple of decades, vitamin A deficiency remains an underlying cause of at least 157,000 early childhood deaths due to diarrhea, measles, malaria, and other infections each year. Vitamin A deficiency is also recognized as a problem that reflects chronic dietary deficiency that may extend from early childhood into adolescence and adulthood, especially for women of child-bearing age. This chapter describes the chemical structure of vitamin A and its precursors, dietary sources, absorption, metabolism and functions, followed by discussions on the epidemiology of vitamin A deficiency, and its role in morbidity and mortality. The chapter concludes with insights on its diagnosis, treatment, and approaches to prevention through dietary improvement, supplementation, fortification, and biofortification.

Conclusions of the Joint WHO/UNICEF/IAEA/IZiNCG Interagency Meeting on Zinc Status Indicators

Zinc deficiency is an important cause of morbidity in developing countries, particularly among young children, yet little information is available on the global prevalence of zinc deficiency. A working group meeting was convened by the World Health Organization (WHO), the United Nations Childrens Fund (UNICEF), the International Atomic Energy Agency (IAEA), and the International Zinc Nutrition Consultative Group (IZiNCG) to review methods of assessing population zinc status and provide standard recommendations for the use of specific biochemical, dietary, and functional indicators of zinc status in populations. The recommended biochemical indicator is the prevalence of serum zinc concentration less than the age/sex/time of day-specific cutoffs; when the prevalence is greater than 20%, intervention to improve zinc status is recommended. For dietary indicators, the prevalence (or probability) of zinc intakes below the appropriate estimated average requirement (EAR) should be used, as determined from quantitative dietary intake assessments. Where the prevalence of inadequate intakes of zinc is greater than 25%, the risk of zinc deficiency is considered to be elevated. Previous studies indicate that stunted children respond to zinc supplementation with increased growth. When the prevalence of low height-for-age is 20% or more, the prevalence of zinc deficiency may also be elevated. Ideally, all three types of indicators would be used together to obtain the best estimate of the risk of zinc deficiency in a population and to identify specific subgroups with elevated risk. These recommended indicators should be applied for national assessment of zinc status and to indicate the need for zinc interventions. The prevalence of low serum zinc and inadequate zinc intakes may be used to evaluate their impact on the target populations zinc status.

Tobacco and obesity epidemics: not so different after all?

Smoking and obesity are two of the most important global health risk factors. Extensive evidence is available on the broader global determinants of tobacco consumption such as trade liberalisation,1 the global marketing of tobacco,2 and smuggling.3 This has led to a comprehensive response from the global public health community, culminating in the Framework Convention on Tobacco Control. At first glance the consumption of food is very different from that of tobacco. After all, food is not a deadly product and people need to eat every day to satisfy basic physiological requirements. Perhaps this is why the public health response to overnutrition has been largely based on the need for individuals to change their behaviour. But this approach is generally ineffective.4 We argue that an analysis of the broader global determinants of overnutrition will lead to a more comprehensive and effective global response. In the United States, obesity has risen by 74% in the past decade, with at least one in five adults now classified as obese.5 Similar trends are seen in most Western countries.6 In the Middle East and North Africa, and in much of Eastern Europe and Latin America, levels of overweight and obesity in women are similar to, or exceed, those of the United States.7 Total energy (calories) supplied by food and beverages has increased as food has become more processed and more energy dense. In North America, fat and sugar account for more than half the total dietary energy intake.8 These changing dietary patterns are becoming mirrored in developing countries. For all developing countries combined, the per capita supply of beef, mutton, goat, pork, poultry, eggs, and milk rose by an average of 50% between 1973 and 1996.9 The transition towards a more energy dense diet is also …

Increasing the production and consumption of vitamin A-rich fruits and vegetables: Lessons learned in taking the Bangladesh homestead gardening programme to a national scale

Micronutrient malnutrition affects more than 20 million children and women (at least 50% of this population) in Bangladesh. the diets of more than 85% of women and children in Bangladesh are inadequate in essential micronutrients such as vitamin A, largely because adequate amounts of foods containing these micronutrients are not available, or the household purchasing power for these foods is inadequate. in Bangladesh and many other developing countries, large-scale programmes are needed to make a significant impact on this overwhelming malnutrition problem. There has been limited experience and success in expanding small-scale pilot programmes into large-scale, community-based programmes. This paper describes the development and expansion of the Bangladesh homestead gardening programme, which has successfully increased the availability and consumption of vitamin A–rich foods. the programme, implemented by Helen Keller International through partnerships with local non-governmental organizations, encourages improvements in existing gardening practices, such as promotion of year-round gardening and increased varieties of fruits and vegetables. We present our experience with the targeted programme beneficiaries, but we have observed that neighbouring households also benefit from the programme. Although this spillover effect amplifies the benefit, it also makes an evaluation of the impact more difficult. the lessons learned during the development and expansion of this community-based programme are presented. There is a need for an innovative pilot programme, strong collaborative partnerships with local organizations, and continuous monitoring and evaluation of programme experiences. the expansion has occurred with a high degree of flexibility in programme implementation, which has helped to ensure the long-term sustainability of the programme. in addition to highlighting the success of this programme, useful insights about how to develop and scale up other food-based programmes as well as programmes in other development sectors are provided.

Zinc deficiency: what are the most appropriate interventions?

Zinc deficiency is one of the ten biggest factors contributing to burden of disease in developing countries with high mortality.1 Since the problem was highlighted in the World Health Report 2002 , calls have increased for supplementation and food fortification programmes.2 3 Zinc interventions are among those proposed to help reduce child deaths globally by 63%.4 Populations in South East Asia and sub-Saharan Africa are at greatest risk of zinc deficiency; zinc intakes are inadequate for about a third of the population and stunting affects 40% of preschool children.5 Zinc is commonly the most deficient nutrient in complementary food mixtures fed to infants during weaning.6 Improving zinc intakes through dietary improvements is a complex task that requires considerable time and effort.7 The case for promoting the use of zinc supplements and for fortifying foods with zinc, especially those foods commonly eaten by young children, therefore seems strong. However, global policies or recommendations for zinc interventions are few. The World Health Organization recommends zinc only as a curative intervention, either as part of the mineral mix used in the preparation of foods for the treatment of severe malnutrition, or more recently in the treatment of diarrhoea.8 We review current evidence that improving zinc intake has important preventive or curative benefits for mothers and young children and examine the programme implications for achieving this in developing countries. We searched PubMed and the databases of WHO and Unicef for information on zinc supplementation and zinc fortification. We examined existing reviews of the evidence for benefits of zinc supplementation and zinc fortification and recent papers reporting the results of randomised controlled trials. These findings were further considered in the light of international policy recommendations for supplementation and fortification of other micronutrients such as iodine, iron, and vitamin …

Carotenoid-Rich Bananas: A Potential Food Source for Alleviating Vitamin A Deficiency

This review article points out that bananas are an important food for many people in the world. Thus, banana cultivars rich in provitamin A carotenoids may offer a potential food source for alleviating vitamin A deficiency, particularly in developing countries. Many factors are associated with the presently known food sources of vitamin A that limit their effectiveness in improving vitamin A status. Acceptable carotenoid-rich banana cultivars have been identified in Micronesia, and some carotenoid-rich bananas have been identified elsewhere. Bananas are an ideal food for young children and families for many regions of the world, because of their sweetness, texture, portion size, familiarity, availability, convenience, versatility, and cost. Foods containing high levels of carotenoids have been shown to protect against chronic disease, including certain cancers, cardiovascular disease, and diabetes. Because the coloration of the edible flesh of the banana appears to be a good indicator of likely carotenoid content, it may be possible to develop a simple method for selecting carotenoid-rich banana cultivars in the community. Research is needed on the identification of carotenoid-rich cultivars, targeting those areas of the world where bananas are a major staple food; investigating factors affecting production, consumption, and acceptability; and determining the impact that carotenoid-rich bananas may have on improving vitamin A status. Based on these results, interventions should be undertaken for initiating or increasing homestead and commercial production.

The impact of consuming iron from non-food sources on iron status in developing countries

OBJECTIVE : To determine the impact of contaminant iron and geophagy on iron intake and status of persons living in developing countries. DESIGN : Literature for review was identified by searching Medline and Agricola, from appropriate other texts and from three reports from the Opportunities for Micronutrient Interventions (OMNI) Project of USAID. SETTING : The dietary intake of iron by people living in developing countries is generally high but iron deficiency remains prevalent. This apparent paradox is because the iron being consumed is predominantly in the non-haem form, which is poorly absorbed. Some of this non-haem iron is from contamination of food with iron from soil, dust and water; iron leaching into food during storage and cooking; contamination during food processing such as milling; and the practice of geophagy. RESULTS : Although the contribution of contaminant iron to overall iron intake is well documented, its absorption and thus its impact on iron status is not. To be available for absorption, contaminant iron must join the common non-haem pool, i.e. be exchangeable. The absorption of exchangeable contaminant iron is subject to the same interactions with other constituents in the diet as the non-haem iron that is intrinsic to food. The limited available evidence suggests wide variation in exchangeability. In situations where a significant fraction of the contaminating iron joins the pool, the impact on iron status could be substantial. Without a simple method for predicting exchangeability, the impact of contaminant iron on iron status in any particular situation is uncertain. CONCLUSIONS : Interventions known to increase the absorption of iron intrinsic to foods will also increase absorption of any contaminant iron that has joined the common pool. Any positive effect of geophagy resulting from an increased intake of iron is highly unlikely, due to inhibiting constituents contained in soils and clays. The efficacy of approaches designed to increase the intake of contaminant iron remains encouraging but uncertain. An approach using multiple interventions will continue to be essential to reduce iron deficiency anaemia.

How to Ensure Nutrition Security in the Global Economic Crisis to Protect and Enhance Development of Young Children and Our Common Future

The global economic crisis, commodity price hikes, and climate change have worsened the position of the poorest and most vulnerable people. These crises are compromising the diet and health of up to 80% of the population in most developing countries and threaten the development of almost an entire generation of children ( approximately 250 million), because the period from conception until 24 mo of age irreversibly shapes peoples health and intellectual ability. High food prices reduce diversity and nutritional quality of the diet and for many also reduce food quantity. Poor households are hit hardest, because they already spend 50-80% of expenditures on food, little on medicines, education, transport, or cooking fuel, and cannot afford to pay more. Reduced public spending, declining incomes, increased food and fuel prices, and reduced remittance thus impede and reverse progress made toward Millenium Development Goals 1, 4, and 5. Investments in nutrition are among the most cost-effective development interventions because of very high benefit:cost ratios, for individuals and for sustainable growth of countries, because they protect health, prevent disability, boost economic productivity, and save lives. To bridge the gap between nutrient requirements, particularly for groups with high needs, and the realistic dietary intake under the prevailing circumstances, the use of complementary food supplements to increase a meals nutrient content is recommended. This can be in the form of, e.g., micronutrient powder or low-dose lipid-based nutrient supplements, which can be provided for free, in return for vouchers, at subsidized, or at commercial prices.