Impacts of Cash Transfer Programs on Rural Livelihoods: a Case Study in the Brazilian Amazon Estuary

We conducted a large household survey in a region of the Amazon estuary in Brazil to investigate the dependence of small farming households on government cash transfers and to identify the main factors that lead to better livelihood outcomes. The study examined the factors that contribute to heterogeneous household livelihoods and patterns of dependence on cash transfer programs. Multinomial logistic regression was used to evaluate household attributes affecting the level of dependence on cash transfers. Results indicate that households engage in a diversity of livelihood strategies, and vary in dependence on cash transfers. Lower levels of dependency are associated with higher levels of education and income from off-farm activities as well as larger property sizes and holdings in the várzea. Recognition of the causes and potential range of dependence on cash transfer programs adds decision-making capacity for policy makers seeking avenues to reduce dependence and increase program effectiveness.     

The Government of Kenya's Cash Transfer Program Reduces the Risk of Sexual Debut among Young People Age 15-25

The aim of this study is to assess whether the Government of Kenya''s Cash Transfer for Orphans and Vulnerable Children (Kenya CT-OVC) can reduce the risk of HIV among young people by postponing sexual debut. The program provides an unconditional transfer of US$20 per month directly to the main caregiver in the household. An evaluation of the program was implemented in 2007–2009 in seven districts. Fourteen Locations were randomly assigned to receive the program and fourteen were assigned to a control arm. A sample of households was enrolled in the evaluation in 2007. We revisited these households in 2011 and collected information on sexual activity among individuals between 15–25 years of age. We used logistic regression, adjusted for the respondent''s age, sex and relationship to caregiver, the age, sex and schooling of the caregiver and whether or not the household lived in Nairobi at baseline, to compare rates of sexual debut among young people living in program households with those living in control households who had not yet entered the program. Our results, adjusted for these covariates, show that the program reduced the odds of sexual debut by 31 percent. There were no statistically significant effects on secondary outcomes of behavioral risk such as condom use, number of partners and transactional sex. Since the CT-OVC provides cash to the caregiver and not to the child, and there are no explicit conditions associated with receipt, these impacts are indirect, and may have been achieved by keeping young people in school. Our results suggest that large-scale national social cash transfer programs with poverty alleviation objectives may have potential positive spillover benefits in terms of reducing HIV risk among young people in Eastern and Southern Africa.     

Do additional SNAP benefits matter for child weight?: Evidence from the 2009 benefit increase

We know that youth who live in low-income households tend to have lower nutritional health outcomes—including higher rates of obesity—when compared to their higher-income counterparts. The Supplemental Nutrition Assistance Program (SNAP) is the largest U.S. federal nutrition program and has been found to improve food security and to serve as an income support. It is less clear how SNAP may affect obesity in low-income youth. From a policy perspective, it is essential to understand how the largest federal nutrition assistance program influences the health of children and adolescents. We use the exogenous increase in SNAP benefits that was a part of the American Recovery and Reinvestment Act (ARRA) to identify how a change in benefits is linked with obesity in youth. We find evidence that the ARRA increase in SNAP benefits is associated with healthier weight outcomes in three of the four age groups examined. SNAP-eligible toddlers are less likely to be overweight and adolescents are less likely to be obese. These findings can help policy makers understand how additional SNAP benefits from the Families First Coronavirus Response Act may influence weight outcomes in children and adolescents.     

“Fish Rescue us from Hunger”: the Contribution of Aquatic Resources to Household Food Security on the Rufiji River Floodplain,Tanzania, East Africa

Inland fisheries are essential to nutrition and food security in developing countries but remain undervalued. Worldwide, studies of aquatic resource consumption are rare. We use data from a monthly survey of 40 households in a Tanzanian village over 1 year combined with qualitative methods to analyse consumption of animal aquatic resources across wealth, seasons, fishing vs. non-fishing, and male- vs. female-headed households. We find that local freshwater fish are the most frequent source of animal protein, consumed on 57% of survey days. Wealth matters, with better-off households eating fish more often and in larger daily quantities on average. Middle-ranked households catch and sell fish more often, but all households double their consumption on average on days they catch rather than purchase fish. Female-headed households rely on gifts to increase consumption. Our results emphasise the need to preserve the livelihood functions of inland fisheries in the face of increasing threats.     

Niveles de micronutrientes en niños escolares colombianos e inseguridad alimentaria

Introduction:

Half of the Colombian households experience some degree of food insecurity. Food insecurity has been associated with malnutrition, which could result in micronutrient deficiencies in children; however, the evidence is not conclusive.

Objective:

To examine the associations between food insecurity and blood concentrations of hemoglobin, ferritin, vitamin A, vitamin B12, folate, and zinc in school-age children from Bogotá, Colombia.

Materials and methods:

We conducted a cross-sectional study among 2,660 children aged 5-12 from Bogotá''s public schools. We assessed their household food insecurity level with the Spanish version of the Household Food Security Survey Module (HFSSM), a validated scale, and quantified blood biomarkers of iron, vitamin A, folate, vitamin B12, and zinc status. We examined the associations between food insecurity, severe hunger, and micronutrient status biomarkers using propensity scores.

Results:

Three-quarters of households had some degree of food insecurity and 12 % had food insecurity and severe hunger. Prevalence of marginal vitamin B12 status and vitamin A and zinc deficiencies were, respectively, 17%, 14%, and 1.4%. Compared with children from households without severe hunger, those exposed to it had lower adjusted mean concentrations of vitamin A, vitamin B12, and folate, but these differences were not statistically significant.

Conclusion:

Food insecurity with severe hunger was not associated with micronutrient status biomarkers in Colombian school-age children. The HFSSM may adequately measure hardship in food acquisition due to lack of resources, but it does not yield an index that is associated with micronutrient status biomarkers.     

The Global Hidden Hunger Indices and Maps: An Advocacy Tool for Action

The unified global efforts to mitigate the high burden of vitamin and mineral deficiency, known as hidden hunger, in populations around the world are crucial to the achievement of most of the Millennium Development Goals (MDGs). We developed indices and maps of global hidden hunger to help prioritize program assistance, and to serve as an evidence-based global advocacy tool. Two types of hidden hunger indices and maps were created based on i) national prevalence data on stunting, anemia due to iron deficiency, and low serum retinol levels among preschool-aged children in 149 countries; and ii) estimates of Disability Adjusted Life Years (DALYs) attributed to micronutrient deficiencies in 136 countries. A number of countries in sub-Saharan Africa, as well as India and Afghanistan, had an alarmingly high level of hidden hunger, with stunting, iron deficiency anemia, and vitamin A deficiency all being highly prevalent. The total DALY rates per 100,000 population, attributed to micronutrient deficiencies, were generally the highest in sub-Saharan African countries. In 36 countries, home to 90% of the world’s stunted children, deficiencies of micronutrients were responsible for 1.5-12% of the total DALYs. The pattern and magnitude of iodine deficiency did not conform to that of other micronutrients. The greatest proportions of children with iodine deficiency were in the Eastern Mediterranean (46.6%), European (44.2%), and African (40.4%) regions. The current indices and maps provide crucial data to optimize the prioritization of program assistance addressing global multiple micronutrient deficiencies. Moreover, the indices and maps serve as a useful advocacy tool in the call for increased commitments to scale up effective nutrition interventions.     

Social Network Analysis Predicts Health Behaviours and Self-Reported Health in African Villages

The provision of healthcare in rural African communities is a highly complex and largely unsolved problem. Two main difficulties are the identification of individuals that are most likely affected by disease and the prediction of responses to health interventions. Social networks have been shown to capture health outcomes in a variety of contexts. Yet, it is an open question as to what extent social network analysis can identify and distinguish among households that are most likely to report poor health and those most likely to respond to positive behavioural influences. We use data from seven highly remote, post-conflict villages in Liberia and compare two prominent network measures: in-degree and betweenness. We define in-degree as the frequency in which members from one household are named by another household as a friends. Betweenness is defined as the proportion of shortest friendship paths between any two households in a network that traverses a particular household. We find that in-degree explains the number of ill family members, whereas betweenness explains engagement in preventative health. In-degree and betweenness independently explained self-reported health and behaviour, respectively. Further, we find that betweenness predicts susceptibility to, instead of influence over, good health behaviours. The results suggest that targeting households based on network measures rather than health status may be effective for promoting the uptake of health interventions in rural poor villages.     

Intergenerational health effects of Medicaid

This paper investigates the effects of the introduction of Medicaid during the 1960s on next generations’ birth outcomes. A federal mandate that all states must widen the coverage to all cash welfare recipients generated cross-state variations in Medicaid eligibility, specifically among nonwhites who largely overrepresented the target population. I implement a reduced-form difference-in-differences strategy that compares the birth outcomes of mothers born in states with higher cash welfare recipiency versus low welfare recipiency and different years relative to the Medicaid implementation year. Using Natality data (1970–2004), I find that Medicaid significantly improves birth outcomes. The effects are considerably larger among nonwhites, specifically blacks. The effects do not appear to be driven by preexisting trends in birth outcomes, preexisting trends in households’ socioeconomic characteristics, changes in other welfare expenditures, and selective fertility. A back-of-an-envelope calculation points to a minimum of 3.9% social externality of Medicaid through income rises due to next generations’ improvements in birth outcomes.     

<Emphasis Type="Italic">Brief Communication</Emphasis>: Does Integration to the Market Threaten Agricultural Diversity? Panel and Cross-Sectional Data From a Horticultural-Foraging Society in the Bolivian Amazon

Trade theory predicts that the expansion of markets induces households to specialize and intensify production. We use plot-level data (n = 64) from a panel study of 2 village and cross-sectional data from 511 households in 59 villages of Tsimane Amerindians (Bolivia) to test the predictions. Results of bivariate analyses using both data sets suggest that as households integrate into the market economy they: (1) deforest more, (2) expand the area under rice cultivation, the principal cash crop, (3) sell more rice, and (4) intensify production by replanting more and by replanting newly cleared plots with maize, another cash crop. Results mesh with predictions about production specialization and intensification of trade theory. The analysis also produced results running counter to predictions from trade theory. For example, households and villages more integrated into the market planted more cassava and rice varieties, intercropped more, and put more crops in new fields than more autarkic households. Although the expansion of markets induces specialization and intensification in selected cash crops, it does not erase completely agricultural diversity. We hypothesize that despite the expansion of markets, households retain agricultural diversity because the market does not yet provide modern forms of self-insurance or well-functioning labor, credit, and product markets that would allow households to protect food consumption when faced with shocks. Without better insurance mechanisms, some agricultural diversity might still allow households to smooth consumption.     

Effect of Health Expenses on Household Capabilities and Resource Allocation in a Rural Commune in Vietnam

Background

Significant health expenses can force households to reduce consumption of items required for daily living and long-term well-being, depriving them of the capability to lead economically stable and healthy lives. Previous studies of out-of-pocket (OOP) and other health expenses have typically characterized them as “catastrophic” in terms of a threshold level or percentage of household income. We aim to re-conceptualize the impact of health expenses on household “flourishing” in terms of “basic capabilities.”

Methods and Findings

We conducted a 2008 survey covering 697 households, on consumption patterns and health treatments for the previous 12 months. We compare consumption patterns between households with and without inpatient treatment, and between households with different levels of outpatient treatment, for the entire study sample as well as among different income quartiles. We find that compared to households without inpatient treatment and with lower levels of outpatient treatment, households with inpatient treatment and higher levels of outpatient treatment reduced investments in basic capabilities, as evidenced by decreased consumption of food, education and production means. The lowest income quartile showed the most significant decrease. No quartile with inpatient or high-level outpatient treatment was immune to reductions.

Conclusions

The effects of health expenses on consumption patterns might well create or exacerbate poverty and poor health, particularly for low income households. We define health expenditures as catastrophic by their reductions of basic capabilities. Health policy should reform the OOP system that causes this economic and social burden.     

Climatic conditions and child height: Sex-specific vulnerability and the protective effects of sanitation and food markets in Nepal

Environmental conditions in early life are known to have impacts on later health outcomes, but causal mechanisms and potential remedies have been difficult to discern. This paper uses the Nepal Demographic and Health Surveys of 2006 and 2011, combined with earlier NASA satellite observations of variation in the Normalized Difference Vegetation Index (NDVI) at each child’s location and time of birth to identify the trimesters of gestation and periods of infancy when climate variation is linked to attained height later in life. We find significant differences by sex: males are most affected by conditions in their second trimester of gestation, and females in the first three months after birth. Each 100-point difference in NDVI at those times is associated with a difference in height-for-age z-score (HAZ) measured at age 12–59 months of 0.088 for boys and 0.054 for girls, an effect size similar to that of moving within the distribution of household wealth by close to one quintile for boys and one decile for girls. The entire seasonal change in NDVI from peak to trough is approximately 200–300 points during the 2000–2011 study period, implying a seasonal effect on HAZ similar to one to three quintiles of household wealth. This effect is observed only in households without toilets; in households with toilets, there is no seasonal fluctuation, implying protection against climatic conditions that facilitate disease transmission. We also use data from the Nepal Living Standards Surveys on district-level agricultural production and marketing, and find a climate effect on child growth only in districts where households’ food consumption derives primarily from their own production. Robustness tests find no evidence of selection effects, and placebo regression results reveal no significant artefactual correlations. The timing and sex-specificity of climatic effects are consistent with previous studies, while the protective effects of household sanitation and food markets are novel indications of mechanisms by which households can gain resilience against adverse climatic conditions.     

Maternal micronutrient disturbance as risks of offspring metabolic syndrome

Metabolic syndrome (MetS) is defined as a constellation of individual metabolic disturbances, including central obesity, hypertension, dyslipidemia, and insulin resistance. The established pathogenesis of MetS varies extensively with gender, age, ethnic background, and nutritional status. In terms of nutritional status, micronutrients are more likely to be discounted as essential components of required nutrition than macronutrients due to the small amount required. Numerous observational studies have shown that pregnant women frequently experience malnutrition, especially in developing and low-income countries, resulting in chronic MetS in the offspring due to the urgent and increasing demands for micronutrients during gestation and lactation. Over the past few decades, scientific developments have revolutionized our understanding of the association between balanced maternal micronutrients and MetS in the offspring. Examples of successful individual, dual, or multiple maternal micronutrient interventions on the offspring include iron for hypertension, selenium for type 2 diabetes, and a combination of folate and vitamin D for adiposity. In this review, we aim to elucidate the effects of maternal micronutrient intake on offspring metabolic homeostasis and discuss potential perspectives and challenges in the field of maternal micronutrient interventions.     

Malnutrition,anemia, micronutrient deficiency and parasitic infections among schoolchildren in rural Tanzania

BackgroundMalnutrition, anemia, micronutrient deficiency and parasitic infections continue to impact the nutritional status and health of children in lower-income countries. However, not enough data concerning this issue is available. The aim of this study was to assess the distribution of nutritional indicators, anemia and micronutrient deficiency and their underlying risk factors among schoolchildren in south-eastern Tanzania.Methodology/Principal findingsThis cross-sectional study enrolled primary schoolchildren aged 6–12 years from Kikwawila and Kiberege wards, Tanzania. In total, 471 schoolchildren underwent a physical examination and provided blood, stool and urine samples for an assessment of the levels of different micronutrients, nutritional and anemia status, and parasitic infection status. We employed bivariate and multivariate logistic regression to determine the association between nutritional statuses, anemia, micronutrient deficiency and parasitic infections. We found that 23.90%, 12.60% and 16.20% of schoolchildren were stunted, underweight and wasted, respectively. About 14.0% of schoolchildren were found to be anemic. Children diagnosed with Plasmodium falciparum infection were more likely to have low levels of ferritin (aOR: 10.40, 95% CI: 2.88-40.53) and elevated levels of serum soluble transferrin receptor (aOR: 3.59, 95% CI: 1.27-11.23), respectively. Vitamin A (34.71%) and vitamin B12 (8.79%) were the most prevalent micronutrients found to be deficient in diagnosed children. Finally, we found that schoolchildren attending the most rural schools were five times more likely to be diagnosed with at least one micronutrient deficiency (aOR: 5.04, 95% CI: 2.38–11.44).Conclusions/SignificanceMalnutrition, anemia and micronutrient deficiency still pose a significant health burden among schoolchildren living in rural Tanzania. To effectively tackle this burden, health interventions such as deworming, micronutrient supplementation, vector control, health education and access to clean water and improved sanitation should be strengthened and made sustainable.     

Offspring migration and nutritional status of left-behind older adults in rural China

Improvements in nutritional status is a principal pathway to good health. This study examines the effect of migration of adult children on the nutrient intake of left-behind older adults in rural China. We use data from four waves (2004–2011) of the China Health and Nutrition Survey and utilize individual fixed effects methods to panel data. Results show that the migration of offspring is associated with significantly higher nutritional status of their left-behind parents, especially higher intake of proteins, carbohydrates, vitamins B1–B3, phosphorus, magnesium, iron, selenium, and copper. The intake of some of these nutrients is below recommended levels. The magnitude of the estimated effects vary between 4% and 24 %. Older adults who live with their grandchildren in rural households or have a low income benefit more from having adult child migrants in the household. The improvement of nutrition outcomes of left-behind older adults is mainly due to increased consumption of cereals, meat, eggs, and fish.     

Community-based natural resource use and management of Bigodi Wetland Sanctuary,Uganda, for livelihood benefits

Conservation and sustainable management of wetlands requires participation of local stakeholders, including communities. The Bigodi Wetland is unusual because it is situated in a common property landscape but the local community has been running a successful community-based natural resource management programme (CBNRM) for the wetland for over a decade. Whilst external visitors to the wetland provide ecotourism revenues we sought to quantify community benefits through the use of wetland goods such as firewood, plant fibres, and the like, and costs associated with wild animals damaging farming activities. We interviewed 68 households living close to the wetland and valued their cash and non-cash incomes from farming and collection of non-timber forest products (NTFPs) and water. The majority of households collected a wide variety of plant and fish resources and water from the wetland for household use and livestock. Overall, 53% of total household cash and non-cash income was from collected products, mostly the wetland, 28% from arable agriculture, 12% from livestock and 7% from employment and cash transfers. Female-headed households had lower incomes than male-headed ones, and with a greater reliance on NTFPs. Annual losses due to wildlife damage were estimated at 4.2% of total gross income. Most respondents felt that the wetland was important for their livelihoods, with more than 80% identifying health, education, craft materials and firewood as key benefits. Ninety-five percent felt that the wetland was in a good condition and that most residents observed the agreed CBNRM rules regarding use of the wetland. This study confirms the success of the locally run CBNRM processes underlying the significant role that the wetland plays in local livelihoods.     

Global malnutrition overlaps with pollinator-dependent micronutrient production

Pollinators contribute around 10% of the economic value of crop production globally, but the contribution of these pollinators to human nutrition is potentially much higher. Crops vary in the degree to which they benefit from pollinators, and many of the most pollinator-dependent crops are also among the richest in micronutrients essential to human health. This study examines regional differences in the pollinator dependence of crop micronutrient content and reveals overlaps between this dependency and the severity of micronutrient deficiency in people around the world. As much as 50% of the production of plant-derived sources of vitamin A requires pollination throughout much of Southeast Asia, whereas other essential micronutrients such as iron and folate have lower dependencies, scattered throughout Africa, Asia and Central America. Micronutrient deficiencies are three times as likely to occur in areas of highest pollination dependence for vitamin A and iron, suggesting that disruptions in pollination could have serious implications for the accessibility of micronutrients for public health. These regions of high nutritional vulnerability are understudied in the pollination literature, and should be priority areas for research related to ecosystem services and human well-being.     

Child nutrition in the transition from nomadic pastoralism to settled lifestyles: individual, household, and community-level factors

The research reported here examines child nutrition in a population that is currently experiencing a transition in subsistence, shifting from nomadic pastoralism to a variety of settled lifestyles. We investigate the range of nutritional consequences of settlement both within and between communities by examining individual, household, and community-level predictors of child nutritional status. Data are drawn from the Rendille Demographic and Health Survey, which contains anthropometric data from 1,088 children ages 6 months to 10 years, as well as socioeconomic data from 640 households drawn from one nomadic and four economically and ecologically diverse settled communities. Comparisons allow us to test the widely held assumption that settlement results in nutritional improvements. The examination of individual and household-level factors highlights several important influences on child nutrition. We find a complex interaction between gender and birthorder, whereby firstborn sons have significantly higher weight-for-height scores than other children, potentially reflecting preference under a system of primogeniture. We also find a complex interaction between defacto female-headed households, where males are absent for over half of the year, and economic status. Young children from poor female-headed households have significantly lower weight-for-height than other children, possibly due to the fact that these households are amongst the poorest in the entire community. However, young children from economically sufficient female-headed households actually fare better than their counterparts in male headed households, suggesting that in households with any discretionary resources, female heads prioritize food acquisition relative to other concerns. Finally, our comparison of child nutritional status across communities, while controlling for individual and household-level variation, does not support the contention that settlement is associated with nutritional improvements. Rather, the effect of community, and its associated changes in subsistence and lifestyle, results in either no nutritional changes, or in the case of young children in the lowland desert community of Korr, diminished nutritional status. Our results underscore the importance of considering variation in sample composition and socioeconomic status when performing community comparisons, and highlight the central role of women in influencing the nutritional welfare of their families.     

Does point-of-sale nutrition information improve the nutritional quality of food choices?

Point-of-sale nutrition information has been adopted by numerous grocery stores to respond to the demand for easy-to-understand nutrition labeling by consumers. Although there is conflicting evidence regarding the effectiveness of providing nutrition information, previous research indicates simplified shelf nutrition labels may lead to healthier choices. However, these studies have not examined how different consumer segments respond to these labels, nor the differential impacts across foods. Using household purchase data from a store that voluntarily adopted the (now defunct) NuVal shelf nutrition labels (a 1-100 numeric score derived from a nutrition-profiling algorithm), we assess NuVal impacts across different consumers and foods. NuVal scores potentially influence not only purchase quantity but also likelihood of buying. Thus, the effect of NuVal was measured by estimating a two-part model and predicting consumers’ unconditional purchase responses. We found evidence of heterogeneous impacts of NuVal across consumers and foods. High-income households and households with children shifted their yogurt and frozen dinner purchases to more healthful items. In contrast, households with children and households headed by heads with college education slightly shifted their canned soup purchases to less healthful options. Our findings suggest that specific foods and consumer segments are influenced by simplified shelf nutrition information and further research is necessary to better understand its effect on consumer dietary quality.     

Improvement of the Vietnamese Diet for Women of Reproductive Age by Micronutrient Fortification of Staples Foods and Condiments

Background

A micronutrient survey carried out in 2010 among randomly selected Vietnamese women in reproductive age indicated that anemia and micronutrient deficiencies are still prevalent. The objective of this study was thus to analyze the dietary micronutrient intakes of these women, to select the food vehicles to be fortified and to calculate their contributions to meet the recommended nutrient intake (RNI) for iron, zinc, vitamin A and folic acid.

Main Findings

Consumption data showed that the median intake was 38.4% of the RNI for iron, 61.1% for vitamin A and 91.8% for zinc. However, more than 50% of the women had daily zinc consumption below the RNI. Rice and vegetable oil were consumed daily in significant amounts (median: 320.4 g/capita/day and 8.6 g/capita/day respectively) by over 90% of the women, making them suitable vehicles for fortification. Based on consumption data, fortified vegetable oil could contribute to an additional vitamin A intake of 27.1% of the RNI and fortified rice could increase the intake of iron by 41.4% of the RNI, zinc by 15.5% and folate by 34.1%. Other food vehicles, such as fish and soy sauces and flavoring powders, consumed respectively by 63% and 90% of the population could contribute to increase micronutrient intakes if they are properly fortified and promoted. Wheat flower was consumed by 39% of the women and by less than 20% women from the lowest socioeconomic strata.

Conclusion

The fortification of edible vegetable oils with vitamin A and of rice with iron, zinc and folic acid are the most promising fortification strategies to increase micronutrient intakes of women in reproductive age in Vietnam. While rice fortification will be implemented, fortification of fish and soy sauces with iron, that has been proven to be effective, has to be supported and fortification of flavouring powders with micronutrients investigated.     

Nutrition: more than the sum of its parts. The modern craze for dietary supplements is under increasing scrutiny, while biofortified crops look promising in the quest to deliver nutrition in developing countries

Increasing evidence suggests that bioengineered plants and healthy diets may be better at delivering nutrition than a cocktail of pills at breakfast time.Micronutrients are big business. Over the past century, scientists have established the ingredients of a healthy human diet, which should include very small amounts of 10 or so trace elements and 13 organic vitamins. The refinement, packaging and sale of these dietary ‘supplements'' has given rise to a vast industry, founded on the principle that a little more of what is good for you cannot be bad. This approach has even been successful for improving the health of people in regions in which micronutrients are scarce in the diet. However, evidence for the efficacy of micronutrient supplements in general, even to alleviate the effects of poverty, has been elusive.At the same time, there is growing anecdotal evidence—now supported by nutritional research—that micronutrients function better when consumed as part of a balanced diet, rather than as pills. The exception is in specific cases of disease or deficiency, where micronutrient supplements can be effective. Yet, even here, it is becoming clear that increasing the micronutrient content of food crops to improve the whole diet offers greater improvements in quality of life and a reduction in mortality. The scientific focus is therefore moving towards the engineering of food plants that contain trace elements and compounds in the right proportions and chemical forms....scientific focus is therefore moving towards the engineering of food plants that contain trace elements and compounds in the right proportions and chemical formsThose studying nutrition are also starting to take a more holistic approach. “I think that it is important to consider micronutrients as part of a network of bioactive constituents within the food and the organism,” commented Jan Frank, group leader for bioavailability and bioactivity of micronutrients at the Institute of Biological Chemistry and Nutrition at Hohenheim University (Stuttgart, Germany). However, Frank admitted that doing so would require new scientific tools and a different emphasis in research. “Scientific experiments are most frequently designed in such a way that only a single parameter, or at the most a few parameters, are changed within an experimental setting.”Nevertheless, there is growing empirical evidence that several micronutrients act in combination rather than in isolation. According to Sabeeha Merchant, head of a research programme on trace-metal metabolism at the University of Los Angeles, California, “if some element B is present in excess, it can have an antagonistic impact on the assimilation of element A [...] One example is molybdenum, where excess amounts can result in reduced copper assimilation.” This sort of deficiency has been observed in domestic and farm animals, especially ruminants (Spears, 2003), that depend on single sources of food.Humans with a varied diet are less likely to suffer from this problem, Merchant noted. Nevertheless, “if variation is reduced, as in the case of isolated communities, then there is the potential for toxicity or deficiency resulting from the presence of elements in the plants,” Merchant said.The ability of micronutrients to antagonize each other could have important implications for human nutrition. For several decades, various interested parties have advised the public to ‘take out insurance'' against deficiency by swallowing more than the minimum recommended dose of key micronutrients. Furthermore, it has been suggested that taking excessively large doses of some micronutrients can protect against infection and disease. The Nobel-prize-winning chemist Linus Pauling could be charged with starting—or at least fuelling—this idea with his insistence that consuming large quantities of vitamin C afforded him extra protection against colds and flu late in his life (Pauling, 1976). He went on to suggest that such high doses might also protect against cancer and heart disease, increase lifespan and make people feel better, even when they are not actually ill (Pauling, 1986). These views have now been largely discredited. Frank commented that, “Overall, there is little evidence to suggest that the intake of micronutrients at concentrations beyond those achievable through a balanced diet may offer additional health benefits.”...it has been suggested that taking excessively large doses of some micronutrients can protect against infection and diseaseAnother point is that some micronutrients are toxic at levels only a few times greater than the minimum recommended dose. A good example, according to Elizabeth Pilon-Smits, head of a research programme focusing on how plants metabolize trace elements and pollutants at Colorado State University, USA, is the element selenium. “For selenium, selenate and selenite are the most toxic forms,” she said. “50–70 micrograms of selenium is needed per day for a human, and no more than 200 micrograms per day should be taken, or it can result in chronic toxicity, so the window is very narrow.”There is one exception to the general rule that a healthy diet provides sufficient quantities of the principal micronutrients. Vitamin D is unique among micronutrients in that its precursor is manufactured through a photosynthetic process that occurs on exposure of the skin to sunlight. However, this only produces adequate vitamin D when the sunlight is relatively strong, and diet alone is unable to make up the deficit during the autumn and winter months across much of the developed world. Partly for this reason, the recommended dietary intake of vitamin D was upgraded in November 2010 from 5 μg to 15 μg per day by the Institute of Medicine of the National Academies in the USA. However, it might be hard to achieve this level without the help of supplements.“The most recent National Nutrition Survey II (Nationale Verzehrsstudie II) in Germany found that more than 88% of Germans did not even meet that recommended daily intake of vitamin D of 5 μg,” Frank noted. “Consequently, it appears questionable whether the potentially higher requirements can be met by diet—especially in the absence of sufficient exposure to sunlight—and consumption of vitamin D-fortified foods and/or dietary supplements may be necessary to maintain optimum health.”Over time, organisms and human populations can adapt to shortages of micronutrients, but this too has an inherent danger: chronic toxicity resulting from consumption of ‘normal'' levels of micronutrients. In such cases, levels that are safe for one group are toxic for another population, as has been observed in the case of Ronaldsway sheep, which live entirely on algae growing by the seashore on the Orkney Islands in the UK. These algae are deficient in copper, and the sheep have become highly sensitive to the element as a result. If they are moved to conventional grass-grazing pastures where they are able to consume—for them—an excess of copper, they suffer from oxidative stress (Haywood et al, 2005).The bigger picture is that the cocktail of micronutrients needed by all organisms is most effective when delivered through foods that contain other ingredients that aid absorption and metabolism. As Frank noted, it is almost common knowledge that vitamins soluble in lipids will only be absorbed efficiently in the presence of dietary fat. “In the context of our own research, we observed that simultaneously ingested phytochemicals, such as sesame lignans (present in sesame seeds and unrefined sesame oil) or alkylresorcinols (in wholegrain cereals, particularly rye) alter the metabolism and excretion of vitamin E” (Frank, 2005)....the cocktail of micronutrients needed by all organisms is most effective when delivered through foods that contain other ingredients that aid absorption and metabolismThis leads to another dimension of the system, which is that micronutrients interact not only with each other, but also with clinical drugs. This has implications for the safety and efficacy of the latter, according to Frank. “For example, substances such as phytochemicals or micronutrients that affect phase I enzymes, may also alter the pharmacokinetics, the activity and ultimately the safety of drugs,” he said.Frank and his colleagues are studying the potential use of curcumin for the treatment and prevention of degenerative diseases including Alzheimer and some cancers. They are part of a three-year research network that started in August 2010, comprising five academic and five industry partners and supported by a €1.5 million grant from the German Federal Ministry of Education and Research. Curcumin is not an essential micronutrient; it is best known as the principal ingredient of tumeric—a spice for curries—and as a colouring agent. However, it also contains powerful antioxidants that might confer protection and act against several diseases.Frank''s research is seeking to address the problem that curcumin is poorly absorbed and rapidly excreted by most organisms. “We are investigating novel combinations of bioactive compounds as well as different formulations and food matrices (meaning complete foods incorporating many micronutrients as well as bulk nutrients such as protein) for their potential to enhance the absorption and retention of curcumin in the body,” Frank explained. “We thus hope to identify new ways of improving the biological activities of curcumin, which may ultimately lead to the development of curcumin-containing functional foods.” Such research is bridging the gap between nutrition and pharmacology.In the immediate future, the greatest health benefits for many people in developing countries will either come from biofortified foods that contain normal levels of micronutrients or, in some cases, from single-nutrient supplements. One of the early breakthroughs came with research conducted by US ophthalmologist and epidemiologist Alfred Sommer, now working at the Johns Hopkins Bloomberg School of Public Health (Baltimore, MD, USA). During the 1970s and 1980s, Somner found that giving a high-dose vitamin A capsule to children deficient in the vitamin cut mortality levels by 34% (Sommer et al, 1986). This research led to several programmes in developing countries for the distribution of vitamin A.Recently, it has become clear that still greater benefits will result from providing micronutrients through the biofortication of food crops that also provide staple calories and protein. Generating and distributing these crops is the long-term objective of HarvestPlus. This programme was set up in 2004 by the Consultative Group on International Agricultural Research (CGIAR) with funding from the Bill Gates Foundation, among other sources, to conduct research on biofortification of crops for developing countries. Its present focus is on three micronutrients recognized by the World Health Organization (WHO) to be deficient in many diets: iron, zinc and vitamin A....greater benefits will result from providing micronutrients through the biofortication of food crops that also provide staple calories and proteinHarvestPlus has been working on a combination of plant breeding and genetics to develop crops that take up more of these micronutrients from the soil and make more of the nutrients bioavailable in the diet. In the case of zinc, fertilizer is applied to boost uptake by the plant in areas where zinc levels in the soil are low. Zinc deficiency itself is widespread, affecting around 25% of the world''s population to some degree and causing a variety of problems relating to the impaired synthesis of proteins and DNA, including reduced resistance to infection and slow wound healing.Although it has taken some time to establish that zinc uptake is increased by the consumption of biofortified plants, HarvestPlus is now convinced that it has firm evidence from field trials (Rosado et al, 2009) and is ready to launch zinc-fortified wheat and maize in India in 2013.One interesting finding from the study is that the bioavailability of zinc depends on the levels of phytates in the crops, salts of phytic acid, which plants use as their primary source of stored phosphorus. Phytates bind (chelate) zinc ions, making them biologically unavailable in a high-phytate diet. HarvestPlus therefore had to take phytate levels into account when determining target zinc levels for its biofortified crops.Biofortification for vitamin A has proven to be more straightforward: the first crop, a conventionally bred sweet potato with a high-vitamin-A content and an orange colour from the associated beta-carotene pigment, was launched in Uganda and Mozambique in 2007. The launch was followed by a study indicating that vitamin A was absorbed more effectively from the crop than from a supplement containing the same amount of vitamin A. People who ate the sweet potato accumulated the vitamin to higher levels, whereas consuming the supplements actually led to a slight decrease in stored levels over time. This suggested that people came to rely entirely on the supplements, although no explanation was given of why this should be (Tanumihardjo et al, 2008).The work by HarvestPlus is already showing that vital micronutrient intake can be increased in developing countries through the use of biofortified crops. There is also plenty of evidence that diseases caused by deficiencies in a particular compound can be tackled with supplements, as in the case of vitamin A. Yet, other studies suggest that the main impact of poverty extends beyond diet and cannot be addressed through improved nutrition alone. Such is the experience from Peru, where a study by the Tuberculosis Research Group at Imperial College (London, UK) has been evaluating whether dietary supplementation with vitamin A, vitamin D and zinc reduces the risk of tuberculosis. The study recruited 800 healthy people in Peru who were at risk of contracting the disease for a randomized, blinded, placebo-controlled trial, which is approaching completion. The results are yet to be published, but preliminary data suggest that supplementation has failed to protect against tuberculosis, according to Carlton Evans, a research career development fellow in Clinical Tropical Medicine at the Wellcome Centre for Clinical Tropical Medicine at the College, and leader of the study.“We have found very clearly that the main determinants of which of these people go on to get tuberculosis are very profoundly socioeconomic. The strongest single factor predicting tuberculosis is not having a cell phone.” Factors such as overcrowding, despair, poor ventilation, stress and the other negative aspects of poverty seem to be at least as important as nutrition. Such conclusions are perhaps not too surprising. The same group began a second study in 2007 to ascertain whether socioeconomic interventions could reduce the incidence of tuberculosis. This work, called Innovative Socioeconomic Interventions Against Tuberculosis (ISIAT), recruited 2,078 people in 311 households in which there were newly diagnosed tuberculosis patients. The researchers conducted visits, held workshops, formed partnerships with existing organizations and provided low-level economic relief, such as by making small lines of credit available. The study is about to publish preliminary findings indicating that these measures can prevent tuberculosis more effectively than micronutrient supplementation.Thus, although Evans agrees that nutrition is important, he argues that poverty is complex and that diseases cannot be cured or prevented just by distributing supplements. He also reiterated that sometimes giving supplements is exactly the wrong thing to do. “It has been shown, for example, that giving iron to people with malaria can cause them to die, because if someone is very frail, spicing up their immune system can be fatal.”...although Evans agrees that nutrition is important, he argues that poverty is complex and that diseases cannot be cured or prevented just by distributing supplementsThe story of nutrition is complex, but a new, more complete picture is emerging. In regions in which micronutrient deficiency is rare, the focus of health professionals, nutrition experts and scientists is on producing and promoting foods containing appropriate forms and proportions of micronutrients. Although the convenience of popping a couple of pills with breakfast appeals to fast-paced modern societies, doing so is not usually an effective way to supplement the diet. In areas of poverty where deficiencies occur, crops that contain balanced proportions of micronutrients are effective—more so than dietary supplements—but improved nutrition must be complemented by socioeconomic measures that address the other causes of disease. Finally, there is a new field of research emerging: what role do micronutrients have in drug effectiveness and safety? The proof of the micronutrient, as they say, will be in the eating.