Which parasite caused the famine?

Solution approaches for hidden hunger

By Ekin Biro & Purnima Menon
October 2014
Photo: Florian Kopp / Welthungerhilfe, Cañadón Peñas, Bolivia, Epifania Ayala's family lives from selling self-made dairy products on the market in the district capital, Oruro. Welthungerhilfe offers training courses and infrastructure for the commercial production of cheese and yoghurt, 2010. Hide

“Hidden hunger” due to a lack of micronutrients does not create the feeling of hunger that we are used to. You may not feel it in your stomach, but it hits the core of our health and vitality.


- Kul C. Gautam, Former Deputy Director of UNICEF

Photo: Gareth Bentley / Concern / Zambia / 2014; Queen, 36, works in her vegetable garden. Queen participates in Concern's RAIN program and has received tools, seeds, livestock and training. Hide

Annotation: This chapter represents the views of the author that may not necessarily correspond to the views of IFPRI, Welthungerhilfe, or Concern Worldwide.

Box 3.1


  • Hunger: Torment resulting from a lack of food

  • Malnutrition: a physiologically abnormal condition caused by an incorrect amount and type of food; this includes malnutrition and overeating

  • Undernutrition: Undersupply with nutritional energy, protein and / or micronutrient deficiency

  • Micronutrient deficiency (also as hidden hunger ): a form of malnutrition in which too few vitamins and minerals are absorbed and processed to ensure health and development in children and normal physical and mental functions in adults. Causes include poor nutrition, illness or an increased need for micronutrients that is not met during pregnancy or breastfeeding

  • Undernourishment: Chronic calorie deficit from intake of less than 1,800 kcal per day, the minimum requirement most people need for a healthy and active life

  • Overeating: excessive intake of energy or micronutrients

Sources: FAO (2013a) and von Grebmer et al. (2013).

Hidden hunger, also known as micronutrient deficiency, affects over two billion people or one in three people worldwide (FAO 2013). It can be devastating, including mental impairment, poor health and productivity, and even fatal as a result of illness. Especially for the health and survival of children in the first 1,000 days of their life from conception to their second birthday, these negative effects are serious and have serious consequences for their physical and cognitive development. Even minor or minor deficiencies can affect a person's well-being and development. Hidden hunger not only harms people's health, it can also inhibit socio-economic development, especially in countries with low and middle incomes.

Another kind of hunger

Hidden hunger is a type of malnutrition in which too few vitamins and minerals (such as zinc, iodine and iron) are absorbed and absorbed to ensure stable health and development (Box 3.1). The factors that lead to a micronutrient deficiency include poor nutrition, increased need for micronutrients in certain phases of life such as pregnancy and breastfeeding, and health problems due to diseases, infections or parasites.

While some clinical symptoms of hidden hunger, such as night blindness as a result of vitamin A deficiency or a goiter due to insufficient iodine intake, become visible in severe deficiency, less obvious, “invisible” effects affect the health and development of much larger populations. This is why micronutrient deficiencies are often referred to as hidden hunger.

Hidden hunger worldwide

Photo: Gareth Bentley / Concern / Zambia / 2014; Chibala, 55, and Catherine, 43, work together in their field. Through gender training as part of Concern's RAIN program, he learned how to help his wife. Hide

Source: Black et al. (2013).

Sources: Allen (2001); Andersson, Karumbunathan and Zimmermann (2012); de Benoist et al. (2008); Wessels and Brown (2012) and Micronutrient Initiative (2009) and WHO (2009; 2014a).
Source: according to ACC / SCN (2000).

Over two billion people worldwide suffer from hidden hunger, which is more than twice as many as the 805 million or so who do not have enough calories available (FAO, IFAD and WFP 2014). Hidden hunger is particularly widespread in large parts of sub-Saharan Africa and the South Asian subcontinent (Figure 3.1). In Latin America and the Caribbean, on the other hand, the values ​​are relatively low. In this region, diet is less based on single staple foods, and extensive micronutrient interventions, nutrition education programs, and basic health services are having an impact (Weisstaub and Araya 2008). Although developing countries are particularly hard hit by hidden hunger, micronutrient deficiencies, above all iron and iodine deficiencies, are also widespread in industrialized countries (Figures 3.1 and 3.2).

The global burden of malnutrition is becoming increasingly complex. The population of developing countries eats less and less conventional, hardly industrially processed foods, but is consuming more and more highly processed, high-energy, but micronutrient-poor foods and beverages. This leads to increased obesity and diet-related chronic diseases. As a result of these changed eating patterns, many developing countries are threatened by a phenomenon that is known as the triple burden of malnutrition: malnutrition, micronutrient deficiency and obesity (Pinstrup-Andersen 2007). In urbanized countries with higher incomes, hidden hunger can be associated with overweight / obesity, caused by excessive consumption of food energy from fats and carbohydrates (Guralnik et al. 2004). It may seem paradoxical, an overweight child can certainly suffer from hidden hunger.

Micronutrient deficiency is responsible for an estimated 1.1 million of the 3.1 million child deaths caused by malnutrition annually (Black et al. 2013; Black et al. 2008). A deficiency in vitamin A and zinc weakens the immune system and thus affects the health and chances of survival of children. Zinc deficiency affects the growth of children and can lead to stunting. Iodine and iron deficits hinder optimal physical and intellectual development in children (Allen 2001).

Women and children have a higher need for micronutrients (Darnton-Hill et al. 2005). The nutritional status of women at conception and during pregnancy has long-term effects on the growth and development of the unborn child.

Nearly 18 million babies are born each year with brain damage from iodine deficiency. Severe anemia kills 50,000 women in childbed each year. In addition, iron deficiency drains the strength of 40 percent of all women in developing countries (UNSCN 2005; Micronutrient Initiative 2014). Measures to combat hidden hunger and improve the nutritional situation usually start with women, infants and young children, as they pay off particularly through improvements in health, nutritional status and cognitive development in the course of life (Hoddinott et al. 2013).

Micronutrient deficiencies are particularly widespread in all age groups due to an insufficient supply of iodine, iron and zinc (Table 3.1, p. 26). Vitamin A deficiency is less common with 190 million children up to five years of age at risk and 19 million pregnant women, but it is no less significant from a public health perspective (WHO 2009). Other vital micronutrients, such as calcium, vitamin D and vitamins of the B group, such as folic acid, are also often not consumed in sufficient quantities (Allen et al. 2006).

Although pregnant women, children and adolescents are considered to be the population groups most severely affected by hidden hunger, it affects people's health in all phases of life (Figure 3.3, p. 26).

It is not easy to document the extent of deficiencies in most micronutrients. There is insufficient data on the prevalence of numerous micronutrient deficiencies. In addition, there are different opinions among scientists about the recommended daily dose for some of the 19 micronutrients that have a direct impact on physical and mental development as well as the immune system (Biesalski 2013). For many micronutrients, the relationship between absorption and utilization in the metabolism has also not yet been adequately clarified.

Obtaining accurate data is a major challenge. Time delays, gaps in data, and lack of breakdown are common problems. Proxy indicators for widespread manifestations of hidden hunger are often imperfect. For example, anemia is used as an indicator of iron deficiency, although only half of all anemia cases are caused by iron deficiency (de Benoist et al. 2008). Typical physical signs of hunger, such as growth retardation (small body size for the respective age; English: "stunting") or emaciation (low body weight for the respective body size; English: "wasting") and underweight, may reflect the micronutrient deficiency of affected population groups, but are unsuitable as makeshift indicators, as micronutrient deficiencies are rarely the only factors involved. Exact measurements through blood samples or specific diagnoses such as night blindness, beriberi and scurvy provide more reliable values ​​for advanced stages of the respective deficiency. Biomarkers have not yet been identified for numerous micronutrients, so there is still no data on the spread of the corresponding deficits. As long as these data gaps persist, it will be difficult to describe the full extent of hidden hunger.

Causes of vitamin and mineral deficiencies

Photo: Gareth Bentley / Concern / Zambia / 2014; Agnita, 59, a community health volunteer, was trained through Concern's RAIN program. At the Luili Health Center she teaches about nutrition in a birth preparation course. May 2014, Zambia. Hide

Box 3.2

The consequences of the green revolution

For many years, public research and development has focused on increasing the production of staple foods to reduce malnutrition. However, the Green Revolution between the 1970s and mid-1990s could have both improved and worsened the food situation through increased production of high-yielding grains. The increase in the total yield of staple foods resulted in a decline in the price of starchy staple foods in relation to more micronutrient-rich foods such as vegetables and legumes. While grains became cheaper for basic supplies, the prices of micronutrient-rich foods rose in some countries, making them less attractive to poor people (Bouis 2000, Kennedy and Bouis 1993).

Inadequate nutrition is one of the most common causes of hidden hunger. A diet that is mainly based on staple foods such as corn, wheat, rice and cassava, which provide a large amount of energy but relatively small amounts of essential vitamins and minerals, often leads to hidden hunger. What people eat depends on a number of factors, including relative prices (Box 3.2) and preferences, which are shaped by culture, peer pressure, and geographic, environmental, and seasonal factors. People with hidden hunger are often unaware of the importance of a balanced, nutritious diet. In developing countries in particular, they often have neither the means nor access to a wide range of nutrient-rich foods, such as foods of animal origin (meat, eggs, fish and dairy products), fruit and vegetables. In the absence of a disaster situation, poverty is the main factor hindering access to adequate, nutritious food. As food prices rise, people tend to continue to eat staple foods and consume less other foods with higher micronutrient content (Bouis, Eozenou and Rahman 2011).

The restricted absorption or utilization of nutrients can also lead to a micronutrient deficit. The absorption can be disturbed by infections or parasite infestation, which can also lead to the loss of or greater demand for numerous micronutrients. Infections and parasites can spread unhindered in unhealthy environments with inadequate water and sanitation and poor hygiene. Unhygienic handling of food as well as food for babies and toddlers can exacerbate nutrient losses even more.

The composition of the diet can also impair absorption. Fat-soluble vitamins, such as vitamin A, can be best absorbed by the body when consumed with fatty foods, while compounds such as tannins or phytates can inhibit iron absorption. Alcohol consumption can also hinder the absorption of micronutrients.

The economic damage

Photo: Gareth Bentley / Concern / Zambia / 2014; Mary Banda, 37, on her field in May 2014. Mary received training and a goat as part of Concerns RAIN program in Zambia. Hide

Figure 3.4 Cycle of hidden hunger, poverty and stagnant development

Sources: Black et al. (2013); IFPRI (2014); FAO (2013a); by Grebmer et al. (2010). Note: The lifelong cycle of malnutrition means that women who were poorly nourished as children are more likely to give birth to underweight babies, thus perpetuating the cycle of malnutrition.

A lack of vitamins and minerals places a heavy burden on the people and societies affected, both in terms of health costs and the negative effects of lost human capital and reduced economic productivity. Hidden hunger impairs physical growth and the ability to learn, restricts productivity and ultimately solidifies the cycle of poverty (Figure 3.4, p. 28). Countries in which large parts of the population suffer from vitamin and mineral deficiency cannot develop their economic potential (Stein 2013; Stein and Qaim 2007). Poor people suffer disproportionately from micronutrient deficiencies and also have to bear long-term negative consequences of hidden hunger on their socio-economic development (Darnton-Hill et al. 2005).

The economic costs of any kind of micronutrient deficiency can be considerable and reduce the gross domestic product (GDP) of most developing countries by 0.7 to 2.0 percent (Micronutrient Initiative and UNICEF 2004). For example, it is estimated that India will lose 1.0 percent and Afghanistan 2.3 percent of their GDP. Worldwide losses in economic productivity due to macronutrient and micronutrient deficiencies reach more than two to three percent of GDP (World Bank 2006) and cause worldwide damage of 1.4 to 2.1 trillion US dollars per year (FAO 2013).

On the other hand, investing in nutrition can be very profitable. Results from expert panels of the Copenhagen Consensus consistently show that nutritional interventions are extremely cost-effective (Copenhagen Consensus 2004, 2008, 2012). In 2008, the panel ranked nutritional supplements for children (vitamin A and zinc), iron and iodine fortification and biofortification among the top five investments in economic development. For example, estimates suggest that every US dollar spent on salt iodination brings in the equivalent of up to US $ 81 (Hoddinott, Rosegrant, and Torero 2012).

Solutions for hidden hunger

Photo: Gareth Bentley / Concern / Zambia / 2014; Monica Malundu, 36, a farmer in Concern's RAIN program, can now support her family. Hide

More nutritional diversity

Increasing nutritional diversity is one of the most effective methods for sustainable prevention of hidden hunger (Thompson and Amoroso 2010). Nutritional diversity influences the nutritional status of children, regardless of socio-economic factors (Arimond and Ruel 2004). In the long term, nutritional diversity ensures a healthy diet with a balanced and sufficient combination of macronutrients (carbohydrates, fats and proteins), vital micronutrients and other nutritional substances such as fiber.For most people, a variety of grains, legumes, fruits, vegetables and animal foods ensure adequate nutrition, although some groups, such as pregnant women, may need food supplements (FAO 2013). There are several effective methods of increasing dietary diversity, including gardening, nutritional education and behavior change in infant and young child nutrition and food preparation, and storage and preservation tips to avoid nutrient loss.

Fortification of commercial foods

Fortifying (fortifying) commercial foods, where staple foods or ingredients are fortified with trace amounts of micronutrients during manufacture, helps consumers get the recommended amounts of micronutrients. Fortification is an easily expandable, sustainable and cost-effective public health strategy and has been implemented with great success, especially in the iodination of salt: today 71 percent of the world's population have access to iodized salt, and since 2003 the number of countries with iodine deficiency has been 54 down to 32 (Andersson, Karumbunathan and Zimmermann 2012).

Fortification methods include fortifying wheat flour with B-group vitamins, iron and / or zinc, and adding vitamin A to oil and sugar. Fortification is particularly useful for urban consumers purchasing commercially processed and fortified foods. Consumers in rural areas, who often have no access to commercially produced food, are barely reached by this measure. To benefit those who need it most, fortification should be subsidized or required by law, otherwise consumers may tend to buy cheaper, non-fortified alternatives.

Fortification has a number of disadvantages, however. People can have reservations about fortified foods. In Pakistan, for example, according to the Micronutrient Initiative, 30 percent of the population avoid the consumption of iodized salt because they believe that iodine leads to infertility and because there have been rumors since 1995 about a secret plan to reduce Pakistan's population growth (Leiby 2012). In addition, it can be difficult to determine the appropriate amount of nutrients in the food. The compounds used for fortification can be unstable and lost during storage or processing. In addition, consumers may refuse to use fortified foods because they change the cooking process or taste. Bioavailability, i.e. the degree or proportion of a micronutrient that can be absorbed by the body, can also be limited. Nevertheless, the research results indicate that the acceptance and effectiveness of enrichment at household level are growing (Adu-Afarwuah et al. 2008; Dewey, Yang and Boy 2009; De-Regil et al. 2013).


Biofortification is a relatively new measure that uses conventional or transgenic methods to cultivate food crops with a higher micronutrient content.

Breeders also improve yields or resistance to pests, as well as properties that are important for consumption, such as taste or cooking time, to outperform conventional varieties. To date, only conventionally grown biofortified plants have been approved for agriculture. Examples are the orange-fleshed vitamin A sweet potato, vitamin A corn, vitamin A cassava, iron-fortified beans and pearl millet, and rice and wheat fortified with zinc. Biofortified varieties are not yet available in all developing countries, but a considerable increase in biofortification is expected within the next five years (Saltzman et al. 2013).

Bio-fortified foods could provide people who cannot be reached by other measures with a constant and safe supply of certain micronutrients. In contrast to the industrial fortification of food, which, if the expansion is successful, mostly reaches the city dwellers rather than the rural population, biofortification is initially aimed at rural areas where the food is produced. Any surpluses generated by the biofortified varieties could be sold in retail stores and thus reach the population first in rural areas and then in the cities.

Since the biofortification of basic foodstuffs cannot achieve such a high content or such a wide variety of minerals and vitamins as the supplementation or industrial fortification of foods, this method is not suitable as a solution for clinical micronutrient deficiencies. However, it can help close gaps in the micronutrient supply and increase the daily intake of vitamins and minerals over the course of life (Bouis et al. 2011). The evidence for the effectiveness of biofortification is not yet complete, but various food crops (iron-fortified beans, pearl millet and rice as well as sweet potatoes, corn and cassava fortified with vitamin A) show evidence of an improved micronutrient status of the consumers (Haas et al. 2005, 2011, 2013, 2014; Luna et al. 2012; Scott et al. 2012; Pompano et al. 2013; De Moura et al. 2014; Tanumihardjo et al. 2013; Talsma 2014; van Jaarsveld et al. 2005). The biofortification of the orange-fleshed sweet potato has significantly improved the vitamin A consumption of mothers and young children (Hotz et al. 2012a; Hotz et al. 2012b).

Food supplements (supplementation)

Dietary supplementation with vitamin A is one of the most cost-effective measures to improve the survival rate of children (Tan-Torres Edejer et al. 2005). Between 1999 and 2005, the distribution more than quadrupled and, according to estimates, covered almost 70 percent of the world's supply needs in 2012 (UNICEF 2014b). Because vitamin A supplement programs have been linked to reduced all-cause mortality and diarrheal incidence, they are often part of national health plans. According to UNICEF, at least 70 percent of all small children between the ages of six and 59 months must be supplied with vitamin A supplements every six months in order to achieve the target reduction in child mortality. Unfortunately, due to fluctuations in funding, the coverage in many priority countries varies greatly from year to year. In addition, vitamin A supplementation is generally only aimed at vulnerable populations between the ages of six months and five years.

Other micronutrient deficiencies are less commonly addressed through dietary supplements. Iron and folic acid supplements are prescribed to pregnant women in some countries; however, the proportion of women who benefit from this measure and the discipline of intake are often low. Micronutrient powder and fat supplements for children at the household level can contain multiple micronutrients, such as iron and zinc. However, it is more difficult than with vitamin A supplements to get large numbers of families to accept them. The learning process for those affected can be lengthy here. In a series of trials in rural China, around half of parents or grandparents stopped giving children food supplements containing soybeans, iron, zinc, calcium, and vitamins because they suspected the free supplements were harmful or counterfeit. They also feared having to pay for it in retrospect (The Economist 2014).


Photo: Gareth Bentley / Concern / Zambia / 2014; Mary Banda, 37, cooking in May 2014. Mary received training and a goat from Concern's RAIN program in Zambia. Hide

A wide range of measures are required to solve the complex problem of hidden hunger. Only a cross-sectoral approach can tackle the underlying causes sustainably at national and international level. National governments must unitedly address hidden hunger in order that the problem receives due attention. Only if all ministries, including the departments for agriculture, health, child development, education and agencies involved in licensing procedures, make joint efforts to improve food and nutrition security, will they have a realistic chance of success. The Scaling Up Nutrition (SUN) initiative provides a model for cross-sectoral collaboration that brings people and resources together at national level to improve nutrition (SUN 2014). Important components of combating hidden hunger are:

  • Behavioral change measures aimed at improving the use of health services, safe water and sanitation, and hygienic behavior to protect women, infants and young children from diseases that affect their nutrient uptake;

  • Messages that support best practices, such as early exclusive breastfeeding until the age of six months, followed by breastfeeding with adequate and adequate complementary foods until the age of 24 months, as an inexpensive and sustainable way to prevent hidden hunger in children;

  • social protection for poor people that gives them access to nutritious food and protection from extreme price rises, as well

  • Empowerment of women through improved access to education.

It will not be easy to eradicate hidden hunger. Big challenges lie ahead. However, they can be tackled if enough resources are allocated, the right strategies are developed, and the right investments are made (Fan and Polman 2014). Much remains to be done to ensure that people around the world have access to the nutritious food they and their communities need to improve their health and develop their full potential.


  1. In conventional breeding, parent lines with a high vitamin and mineral content are crossed with one another over several generations in order to obtain plants with the desired properties. Transgenic approaches, in which genes are manipulated or new genes are inserted, serve to introduce nutrients into a food plant that do not naturally occur in it (for example, provitamin A in rice).