ALLEVIATING Hidden Hunger Approaches that work by Eileen Kennedy, Venkatesh Mannar & Venkatesh Iyengar he world has come a long way at the national level. The payoff for in understanding the nature, eliminating hidden hunger through Tmagnitude and range of nutrient fortification is enormous and solutions to micronutrient malnutrition few other public health interventions – often called “hidden hunger”. The offer such a promising health, most sustainable solutions – that is nutrition and economic success story. those that are likely to be maintained Nuclear and isotopic techniques in the long term – almost surely will are valuable tools in helping to meet include food-based approaches the multifaceted challenges posed by including diet diversity, food nutritional disorders affecting the fortification and biofortification. Food entire human life span (embryonic to fortification and biofortification could elderly). Among the numerous be some of the most cost-effective of applications available, isotopic all public health interventions and techniques are uniquely well suited thus within the economic reach of for targeting and tracking progress in even the world’s poorest. In order to food and nutrition development implement them in a sustainable programmes (See box: How Nutrients manner, a combination of technical, are Tracked). These include: use of operational, economic, behavioural the stable isotopes of iron (Fe) and Despite abundant global and political factors need to be zinc (Zn) as a kind of gold standard in food supplies widespread addressed. In some ways the studies of their bioavailability from technological issues are the easiest. foods; trace element bioavailability malnutrition persists in Because of attention to research, we and pool sizes for measuring the many developing countries now have a variety of ways for both effectiveness of nutrition supple- Micronutrient malnutrition single and multiple micronutrients to mentation or fortification trials; reach the target population. We also isotope dilution methods used in the is particularly damaging know what is needed in order to assessment of vitamin A status tracing but it can with relative ensure delivery systems. The key through carbon-13 (13C) carotenoids. ease be eradicated factor for continued success in Further, specialized applications reducing micronutrient malnutrition – namely neutron activation analysis through fortification is a political and inductively coupled plasma mass commitment at the national and spectrometry – permit simultaneous international level and creating analysis of a range of minor and trace effective public-private partnerships elements in foods and beverages. 54 IAEA BULLETIN 45/1 Hunger pains Alleviating the entire child bearing age (especially during pregnancy) needs In the early 1990s the problem of “hidden hunger” to be continued indefinitely. A clear “hidden hunger” commanded The basic objective of all national “success story” is the improvement in worldwide attention. Through a series micronutrient programs is to ensure the vitamin A status of preschool-aged of high-level conferences, including that needed micronutrients are children using high dose the 1992 international conference on available and consumed by vulnerable supplementation. nutrition in Rome, it became apparent populations. Programmes directed At least 90 countries routinely that large parts of the developing towards the sustained elimination of provide vitamin A supplements to world were plagued by micronutrient micronutrient deficiencies need to be young children in developing malnutrition which could not be seen broadly based so that interventions countries. Using the National but which had devastating health and become accepted community practices. Immunization Day’s (NID) infra- nutritional consequences. The Hence, program strategies need to go structure, countries have been able to problem not only is an impediment to well beyond conventional health and provide vitamin A supplements in health but also compromises nutrition systems and be based upon efficient and cost effective ways. socioeconomic development, learning empowering people and communities More than 75% of all young children ability and productivity. to be capable of arranging for and in countries where vitamin A The numbers of affected people sustaining an adequate intake of deficiency is known to be common worldwide are staggering. Globally micronutrients, independent of external received high-dose vitamin A some 250 million children are at risk of support. Such strategies must be capsules in 2002, compared to only vitamin A deficiency – a leading cause multi-sectoral and integrate interventions about one-third in 1994. However, of childhood blindness. And, in with social communications, evaluation with the virtual elimination of polio in countries where immunization and surveillance components. many developing countries, NID’s are programs are not widespread and In addressing micronutrient being phased out over time. vitamin A deficiency is common, malnutrition in a country, a Governments and international millions of children die each year from combination of strategies involving institutions are turning to alternative complications of infectious diseases the promotion of breast feeding, supplement delivery channels as a such as measles with 2.8 million dietary modification (e.g., improving means of sustaining these gains. showing frank signs of xerophthalmia; food availability and micronutrient However, in the medium to long term, two billion people suffer from anemia bioavailability, and increasing food the objective should be to increase or iron deficiency which the World consumption), food fortification and daily intake of all micronutrients Health Organization (WHO) cites as the pharmaceutical supplementation needs through food either in natural forms or most widespread nutritional disorder in to be emphasized and implemented. through fortification. the world and 1.5 billion people live in The different complementary approaches Food fortification is not a new areas where iodine deficiency disorders are often implemented in three phases: nutritional intervention. Post World continue to be a threat. Insufficient a) to ensure relief to vulnerable groups War II, fortification with a range of iodine in the diet is the most common – through supplementation, b) to improve nutrients became common in the yet also most preventable – cause of micronutrient intakes across the United States and some parts of brain damage throughout the world. population in the medium-term Europe. Food fortification was a key While the numbers are staggering based through food fortification and c) to factor in eliminating rickets (vitamin on deficiencies of iron, iodine and ensure sustained, long-term outcome D in milk), goitre (iodine in salt) and vitamin A, it has become apparent that a through dietary diversity coupled with pellagra (niacin fortification of cereals range of other micronutrients are also biofortification of staple crops. and other grains) and has also been lacking in the diets of low-income Supplements provide immediate effective in reducing the incidence of households such as zinc and folic acid. relief to vulnerable populations and iron deficiency. Worldwide, Particularly vulnerable within the low- age groups with special micronutrient fortification of salt with iodine has income population are infants, needs, e.g. pregnant and lactating produced major reductions in iodine children, pregnant women and the mothers and pre-school age children. deficiency disorders. However, with elderly given their special nutritional In some cases supplementation for the exception of iodine in salt, food and health needs. women during adolescence through fortification has not yet been used June 2003 55 he major cause of micronutrient deficiencies is of excess phytates and fibres that influence a lack of adequate intake of bioavailable mineral absorption. Tminerals and vitamins from the staple diets. Importantly, such techniques also help to identify This is exacerbated by the fact that commonly those foods or fortificant-based interventions most consumed foods and beverages (such as rice, wheat, likely to succeed in target populations. Stable isotopes corn, legumes, tea and coffee) are high in inhibitors are safe for use in children and pregnant women, and low in enhancers of micronutrient absorption. feasible for field application and assess changes Thus, these staple foods such as cereals and legumes within reasonable time and cost. In the food are not only poor sources of bioavailable micronutrients fortification area the use of isotopic techniques is now but also interfere with the absorption of the well established for enhancing sensitivity of nutrition micronutrients added during the process of intervention trials. fortifying foods. Using the isotopic approach (in vivo and in vitro), Biochemical processes influencing the determinations of bioavailability can be carried out. bioavailability (or the fraction of a nutrient our body’s Laboratory assessment of bioavailability (in vitro) – by metabolism absorbs) are inherently complex. That is simulating the human stomach – measures the why the choice of the compound to be used as a percentage of iron that is potentially available. It is the fortificant is critical. This depends in part on its only rapid tool using radioactive isotopes to compare solubility in the gastric juice, besides its impact on bioavailability from different foods and diets. It can