Giving What We Can no longer conducts our own research into charities and cause areas. Instead, we're relying on the work of organisations including J-PAL, GiveWell, and the Open Philanthropy Project, which are in a better position to provide more comprehensive research coverage.
These research reports represent our thinking as of late 2016, and much of the information will be relevant for making decisions about how to donate as effectively as possible. However we are not updating them and the information may therefore be out of date.
Micronutrients are substances needed only in minuscule amounts that enable the body to produce enzymes, hormones and other substances essential for health and growth. The consequences of micronutrient deficiencies can be severe. Iodine, vitamin A and iron are the most important in global public health terms; their lack represents a major threat to the health and development of populations the world over, particularly for children and pregnant women in low-income countries.[1]
Mass fortification involves adding micronutrients to staple foods and appears to be one of the most effective means of combating micronutrient malnutrition. Giving What We Can has reviewed studies documenting nutritional improvements in populations as a result of mass fortification. Reported ‘benefit-cost’ ratios are at 5 or higher, and in some cases over 20. The reported cost of giving one person an extra year of life due to improved health ranges widely, but in many cases falls between $20 -$100. However, the validity of these studies is open to question and there are reasons to be cautious in interpreting the available data. Although our research has mainly focused on food fortification, other promising interventions for combating micronutrient malnutrition also exist and deserve further research.
Iodine deficiency is the world's most prevalent, yet most preventable, cause of brain damage. Serious iodine deficiency during pregnancy can result in stillbirth, spontaneous abortion, and congenital abnormalities such as cretinism, which is a grave, irreversible form of mental retardation affecting people living in iodine-deficient areas of Africa and Asia. However, of far greater significance is that a deficiency in iodine leads to a less visible, yet more pervasive mental impairment that reduces intellectual performance in school and at work.[2]
Vitamin A deficiency is the leading cause of preventable blindness in children and it increases the risk of disease and death from severe infections. In pregnant women, vitamin A deficiency causes night blindness and may increase the risk of maternal mortality.[3]
Iron deficiency is the most common and widespread nutritional disorder in the world. Two billion people – over 30% of the world's population – are anaemic, many due to an iron deficiency, and in resource-poor areas this is frequently exacerbated by infectious diseases. Iron deficiency and anaemia reduce the work capacity of individuals and cumulatively, entire populations, bringing serious economic consequences and obstacles to national development.[4]
Micronutrient malnutrition (MNM) is a severe global health issue especially common in the developing world that can lead to increased mortality and morbidity. The Copenhagen Consensus 2008 Challenge Paper on ‘Malnutrition and Hunger’ estimated that maternal and child malnutrition is the underlying cause of 11% of total global DALYs (Disability-Adjusted Life Years), and argued that combating MNM would be a crucial step towards achieving the Millennium Development Goals for primary education and child mortality.
The World Bank’s ‘Global Monitoring Report 2012: Food Prices, Nutrition, and the Millennium Development Goals’ stated that malnutrition – including MNM – could potentially impact all eight Millennium Development Goals.
It has also been suggested that micronutrient deficiencies can impact economic productivity, growth and development. For instance, researchers have claimed that iron deficiency causes China to lose 3.6% of Gross National Product through reduced productivity.[5]
Overall, the Copenhagen Consensus judged that combating malnutrition through micronutrient fortification was one of the highest-return investment opportunities in the world, with estimated cost- benefit ratios ranging from 7.8:1–39:1, depending on the micronutrients used.
The three most important forms of MNM according to WHO’s ‘Role of Food Fortification’ report are iron, vitamin A and iodine deficiency. The WHO states that one in three of the world’s population suffer at least one of these deficiencies6, with the majority of individuals affected residing in the developing regions. Table 1.1 from this report shows the prevalence of these three deficiencies:
This report did not include data concerning the prevalence of other important deficiencies, such as zinc; it appears the public health implications of other deficiencies are less well understood.
The health impacts of micronutrient deficiency are estimated in WHO’s ‘Global Burden of Disease’ report: each year: iron-deficiency anaemia results in 25 million DALYs globally, vitamin A deficiency in 18 million DALYs and iodine deficiency in 2.5 million DALYs. These figures may underestimate the overall health impact of MNM, because DALY figures usually do not embody the smaller yet widespread health effects that can result from deficiencies, nor the effects these can have on cognitive abilities.
Apart from the ‘big 3’ deficiencies, many other micronutrient deficiencies appear to have severe health consequences. Diagram 1.2, constructed using information from the WHO report, gives a simplified overview of micronutrient deficiencies and their main health impacts.
Diagram 1.2: Alleviating MNM
Dietary diversification might be the ‘ideal’ option for addressing MNM, which entails individuals receiving a varied and healthy diet. However, this approach would be very costly and take a long time to implement and reap the benefits.
Options b–d are approaches that are more likely to be effective, given scarce resources and time pressures. Other policy initiatives in developing countries include options e-f.[7]
Fortification is the practice of deliberately increasing the proportion of micronutrients in food, to improve its nutritional quality and ultimately, to improve public health[1]
Referring to Diagram 1.3, fortification can be[2]
Diagram 1.3: Types and Implementation of Fortification
The most common food fortification policy is that of salt iodisation7; the latest Global Unified Matrix database states that 55 out of 117 developing countries had legislation enacted for Universal Salt Iodisation by 2005 (and additional countries have enacted such legislation since then). Sugar is fortified with vitamin A in most of Central and South America, and it is estimated that around 95% of households are reached in El Salvador and Guatemala.[8]
In principle, the main advantages of food fortification are as follows[9];
The Flour Fortification Initiative claims that seventy-five countries worldwide require fortification of one or more types of wheat flour. These include developed, transitional and developing countries.[10]
Empirical evidence from several studies suggests that fortification can be an effective means of reducing MNM. For example, we have found evidence that:
However, some micronutrient fortification strategies have proved less effective. An example is the fortification of monosodium glutamate with Vitamin A in Indonesia, which was stopped due to political and technical issues (one of the technical issues was that, even though under laboratory testing the vitamin A remained white, once in the sun the product became discoloured which concerned producers and customers)[13]
Some potential disadvantages of fortification exist:
Some evidence suggests fortification to be one of the most cost-effective strategies to deal with MNM. The Copenhagen 2008 ‘Malnutrition and Hunger Challenge’ Paper claims that zinc fortification costs only $12.20 per DALY averted, whilst zinc supplementation averts a DALY with each $63.
The Copenhagen Consensus 2008 states that iron fortification and salt iodisation are the second-most cost-effective strategies to cope with micronutrient deficiencies, with micronutrient supplements for children (vitamin A and zinc) coming first, and biofortification (breeding crops with enhanced nutritional benefits) coming third.
The WHO has a calculation they use to estimate the cost per year of life saved by Vitamin A fortification17. They take the current death rate for which vitamin A is responsible (deaths due to Vitamin A deficiency per 1,000 people), and assume fortification would bring this down to 0. They combine this with information about the cost per 1,000 people reached with fortification. Dividing years of lost life averted by cost, they produce an estimated cost per year of life saved of $18.60. This cost-effectiveness is extremely high.
The WHO estimates a cost:benefit ratio for iodine fortification of 1:26.5, based on the assumption that iodine's unit cost is $0.10. However, they note that some experts put the unit cost as low as $0.01 in some areas of Sub-Saharan Africa (which would change the ratio to 1:265). The estimation assumes that iodine fortification will completely eradicate goitre in the treated area, which may be inaccurate. The costs of iodine deficiency in this model derive from productivity losses of 10% when pregnant mothers have goitre, so the calculations are also dependent on the country’s average wage.
The WHO estimates the economic returns for iron fortification (as a result of increased productivity) as $8 for every $1 spent (1:8 cost:benefit ratio), based on fortification costing $0.12 per person, reducing deficiency in 24% of the population, and economically benefiting each person helped by $4 of wages. However, the last figure ($4) is from a model of the Venezuelan economy - we should expect productivity gains to differ by country.
Table 1.4 summarizes the Copenhagen 2008 Malnutrition and Hunger Challenge Paper’s literature review of the cost-effectiveness of micronutrient fortification programmes. This paper uses benefit:cost ratios by converting DALYs averted into economic 'equivalents’[18]
Table 1.4: Summary of Micronutrient fortification benefit:cost ratios (CC 2008)
The more recent Copenhagen Consensus 2012 Challenge Paper on Hunger and Malnutrition published the following results (Table 1.5) from a further literature review on the benefit:cost ratios of micronutrient interventions.
Table 1.5: Summary of Micronutrient fortification benefit:cost ratios (CC2012)
CC12's estimate for the benefit:cost ratio of salt iodisation is promising, despite the very large range reported. This high benefit:cost ratio was derived from an average impact and cost across all individuals in the population, not just pregnant women or young children.
Cost:benefit ratios for iron fortification in general and of wheat flour in particular are lower than the proposed benefit:cost ratios of iron home fortification and iron biofortification (though the former may still be highly cost-effective).
Sue Horton estimates the cost-effectiveness of mass fortification in terms of DALYs averted per $. Her results are depicted in Diagram 1.6[19]
Diagram 1.6. Horton’s Results: Cost-effectiveness of Fortification
Horton’s estimates compare the cost-effectiveness of iron, vitamin A, and zinc fortification and supplementation in the sample population, ‘Africa E’ (Fig. 1). She estimates that fortification is many times more cost-effective than supplementation. Each form of fortification averts a DALY for less than $60, suggesting high cost-effectiveness. Fig. 2 highlights her claim that the cost-effectiveness of fortification varies significantly by region.
Table 1.7 summarises the cost-effectiveness (I$/DALY) estimates of several different approaches, detailed below.
Table 1.7. Summary of Literature: Cost-effectiveness of Fortification
*Costs are expressed in international dollars (I$), One I$ has the same purchasing power as one US$ has in the USA, costs in local currency units are converted to I$ by use of PPP. **Assuming 80% coverage. AfrD ,Africa subregion with high rates of adult and child mortality; AmrB, South American subregion with low adult and child mortality; EurA, European subregion with low adult and very low child mortality; SearD, Southeast Asian subregion with high rates of adult and child mortality.
The literature used to compile Table 1.7 makes the following claims about the cost-effectiveness of fortification compared to supplementation:
Table 1.8: Cost-effectiveness of iron fortification and supplementation at 50% and 95% coverage rates:
Fortification has thus been found to be cost-effective at <$100 per="" daly="" averted="" in="" a="" variety="" of="" contexts.="" however,="" the="" cost-effectiveness="" differs="" several-fold="" by="" region="" and="" study,="" meaning="" that="" it="" remains="" challenging="" to="" confidently="" judge="" likely="" any="" particular="" future="" project.<="" p="">
Some concerns we have about relying on the existing literature are:
Last updated: 2013