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Solutions for Micronutrient Deficiency


You will never understand violence or nonviolence until you understand the violence to the spirit that happens from watching your children die of malnutrition.

- a peasant in El Salvador (quote from Witness to War)

The recent destruction of Golden Rice trials in the Philippines has me thinking again about how crop genetics, including biotechnology, can help in reducing malnutrition. Greenpeace and others would have us believe that home gardening and supplements are the solution, but unfortunately it’s just not that simple. On the other side, I’ve seen quite a few short posts dismissing the potential of gardens and supplements but haven’t seen anyone go into the details. Let’s examine them thoroughly.

The problem

Let’s start with some good news: we have made great strides in reducing hunger. Millennium Development Goal number 1c, set by the United Nations in 2000, was to “halve, between 1990 and 2015, the proportion of people who suffer from hunger”. We are on target to meet that goal, but despite these efforts, “about 870 million people are estimated to be undernourished”.

Low, medium, and high severity of the most common micronutrient deficiencies—vitamin A, iron, and zinc—among children under 5 prevalence data. Data from the WHO, image from HarvestPlus.


Now for the bad news: the problem of hidden hunger – micronutrient deficiency – affects far more people than hunger. It can be difficult to count those affected, but it’s estimated that people with micronutrient deficiencies number in the billions. About 1 in 3 people are affected, according to the Micronutrient Initiative. Vitamin and mineral deficiencies are hardest on children – reducing their ability to fight infection and negatively affecting development of the brain and other organs. (For specific information about different micronutrients, see Investing in the future: A united call to action on vitamin and mineral deficiencies.)

If you have x dollars to spend, and prices go up, the percentage of your money that is needed for staples increases, leaving you with less money for other foods and goods. Figure adapted from HarvestPlus with permission.


Micronutrients like vitamin A, iodine, iron, zinc, and folate are taken for granted in diverse Western diets. We have a thriving supplement industry, but the fact is that the grand majority of us get more than enough micronutrients from our food. We have access to lots of fruits, vegetables, meat, and dairy, and if that isn’t an option due to taste, time, or income, we have access to fortified processed foods from breakfast cereal to pasta.

Unfortunately, most humans do not have access to a diverse diet or even a fortified one. Many people subsist on a staple crop such as rice, maize or cassava. This isn’t by choice – it’s just that the staples are less expensive. Staple crops aren’t staples because they are nutritious. They can be grown cheaply or they are all that will survive in local agriculture. Sadly, this isn’t a new problem. The epidemic of micronutrient deficiency has been with us for as long as there have been people without access to diverse diets.

Micronutrient deficiency increases as food prices increase, whether globally or locally. Since staples are the primary calorie source, an increase in prices means less money for buying other foods and goods, as shown in this diagram. For example, when drought struck Ethiopia in 2011, people went from buying maize plus sugar, oil, and vegetables, to just maize.

The solutions

The ultimate solution to micronutrient deficiency is reduction of poverty and access to diverse diets. Instead of rice for dinner, if people could have rice, meat or beans, and some vegetables or fruits, they would easily meet their body’s needs for not only calories but protein and micronutrients as well. Simple, right? Unfortunately not.

While we would all wish away poverty if we could, it is a long-term problem that will require major societal changes. We need to make incremental efforts to help people until that happy day that poverty is eliminated. Many strategies have been used to improve nutrition. These include gardens, supplements, changes in how foods are prepared, fortification, and biofortification. Each has advantages and disadvantages, and ultimately, each has a role to play in reducing hidden hunger.


Gardens of nutrient-rich fruits and vegetables in homes, schools, and communities are wonderful ways to reduce micronutrient deficiency and to help people climb out of poverty. Small and large non-profit organizations have accomplished great things in this arena. There have been valuable successes reported in the literature, when interventions included culture- and location-appropriate training as well as supplies such as seeds and tools. However, lack of properly designed studies makes it difficult to determine the effect of gardens on micronutrient deficiency.

While the benefits of gardens to participating families and communities cannot be overestimated, the reach of these programs only goes so far. They only work for people with access to land, which may rule out the poorest people as well as many in urban areas. The most nutritious plants may not be acceptable culturally or may not be suited for local climate conditions. Gardens can be decimated by pests, drought, and floods, and may only produce food during certain parts of the year, depending on the climate and the plants selected. Gardens are not a good idea in communities where soil has high levels of heavy metals either naturally or due to contamination.

In addition to gardens, providing animals for meat and milk can help improve micronutrient deficiency. Heifer International has “helped more than 18.5 million families by providing livestock and environmentally sound agricultural training to improve the lives of those who struggle daily for reliable sources of food and income”. An amazing accomplishment, but animals have many of the same drawbacks as gardens.

Overall, gardens are an admirable activity with the ability to help many people. With better research, we may even find that gardens maintain long-term impact in reducing micronutrient deficiency. In the meantime, though, other efforts are necessary.


Supplementation is the primary method that has been used in attempts to reduce micronutrient deficiency. Daily vitamins are impractical for a variety of reasons (lack of supply chains and high costs are major ones), so megadoses are used yearly or a few times a year. These approaches have had great success, but also have their drawbacks.

Problems associated with supplementation in developing counties include low acceptance rates, quality control, potential side effects such as nausea, and potential over-supplementation (with specific problems depending on the specific micronutrient being supplemented). Then we have all of the issues associated with delivery, such as inaccessible populations in rural or mountainous regions and interruption of delivery due to situations such as war.

Thankfully, most supplements are inexpensive. In the case of vitamin A, only 5% of the cost of supplementation is the vitamin itself. The other 95% of costs are labor, marketing, training, and administration of the program. The cost of supplementation is lowest where labor is cheapest. In 2007, the cost per supplement for vitamin A was about $0.50 in Africa, $1.00 in Asia, and $1.50 in Latin America. Not bad! But we have to multiply that by at least twice per year throughout childhood and adolescence and again for pregnant or nursing women. Then multiply by the number of people that need micronutrient supplements. And remember that many people are deficient in more than one micronutrient. Those costs keep rising as population grows.

Micronutrient Absorption

Certain preparation methods of foods can make the nutrients easier to digest, while other preparation methods destroy nutrients. For example, adding lactic acid during tortilla preparation can make the iron in corn flour more bioavailable. Cooking cassava into gari reduces beta-carotene levels compared to fufu or boiling.

Simply changing how meals are eaten can make nutrients more digestible too. Iron is a particularly finicky nutrient: iron becomes more bioavailable when consumed with vitamin c (such as orange juice or tomato sauce) but less bioavailable when consumed with calcium (milk) or tannins (tea, coffee, red wine). Beta-carotene (the pre cursor of vitamin A) is better absorbed if vegetables are eaten at once rather than smaller portions during the day. Beta-carotene is also better absorbed when consumed with fats such as vegetable oil.

These differences in digestibility don’t matter to those of us with plenty of food and diverse diets, but can have health implications in those with micronutrient deficiencies. Changes in preparation methods or eating patterns can help people to make the most out of nutrients that they already have in their diets. Unfortunately, while the changes might be simple, it takes a lot of effort to provide the information to people. It can be very difficult to change traditions. It may require addition of ingredients that aren’t typically included in meals, potentially increasing cost. Finally, it can be difficult to combine all of these recommendations into recommended diets that are culturally relevant for populations with deficiencies.


Instead or in addition to changing how foods are prepared at home, changes to industrially prepared foods can have positive impacts on micronutrient deficiency. If fortification is added to foods that are widely used, then high percentages of populations can be reached, using supply chains that already exist. Success stories in the US include iodine in salt, vitamin D in milk, niacin in bread, and folic acid in all grain products. In developing countries, success stories include iodine in salt and iron in fish sauce and soy sauce.

A potential example of how fortification could make a big difference was recently reported by NPR’s Eliza Barclay in Ramen To The Rescue: How Instant Noodles Fight Global Hunger. Ramen, while not very nutritious, is an affordable, non-perishable, belly-filling food that is consumed around the world. Of course the ideal situation would be for people to eat ramen only in moderation and eat healthy foods with fruits and vegetables, but that’s just not realistic. A “better way to help the poor who rely on ramen is to make the noodles more nutritious: They could be "reduced-sodium, lower-fat, higher-fiber, better fortified," though that will also translate into a slightly higher price.” If ramen could be fortified with micronutrients but the cost kept down, it would have a huge positive impact.

Of course, there are downsides to fortification, too. It requires a will from either government or food processors (preferably both) to make major changes. Fortification requires people with nutritional deficiencies to have regular access to industrially processed foods, which is not the case in many rural areas. Small-scale fortification at schools and other local institutions can help reach additional people.


Instead of adding nutrients to foods, the nutrients found in staple crops can be improved directly with selective breeding or biotechnology. Biofortification eliminates the need for a central distribution system. Once seeds are distributed, no additional or repeated intervention is needed. If crop varieties that are already grown and consumed in the areas of need are biofortified, then just a simple one-for-one switch is needed. Even better, increased micronutrient traits can be combined with agronomic traits such as disease resistance and drought tolerance.

Biofortification is a cost-effective intervention, estimated to be less costly per life saved than supplementation. Biofortification is such a promising way to reduce micronutrient deficiency that it is one of the Grand Challenges of the Gates Foundation. Successes of breeding include increased iron, zinc, and manganese in wheat, increased iron in rice and in beans, and increased beta-carotene in maize. In some cases, desired improvements are not possible with breeding, so biotechnology can be used.

Frank N. Foode , mascot of the Biofortified Blog, poses with some orange maize that has been bred to express very high levels of beta-carotene. Follow Frank’s adventures on twitter: @franknfoode Photo by Anastasia Bodnar.


One caveat is that biofortified seed must be made available at low or no cost in order to have the greatest possible levels of adoption. This means there is little financial incentive for corporations for research and development of biofortified varieties. Publically funded, locally driven efforts have the greatest potential. Still, public-private partnerships have potential as well. Some of the most promising efforts in biofortification have public and private partners. Syngenta, for example, has been involved in the well-known Golden rice as well as little-known biofortified sorghum.

A problem with biofortification is acceptance. Education efforts may be needed in cases where the biofortified crop looks different, such as when beta-carotene is the target micronutrient. For biotechnology, use of the genes from the same species or related species may be better accepted than use of genes from different species. Demonstrations of efficacy are likely to sway those with micronutrient deficiencies, as has happened with biofortified orange sweet potato and orange maize.


As we strive as a species to eliminate hunger and poverty, we must take steps to eliminate suffering however we can. Smaller efforts to improve micronutrient status have a snowball effect as well-nourished children grow up to be stronger adults and can help pull their communities out of poverty. It will take a combination of efforts, including gardens, supplements, food preparation methods, fortification, biofortification, and more to reach all people in need. It makes no sense to reject any of the possible solutions in favor of one or the other. There is no silver bullet, but we have silver buckshot.

Images: Fig. 1: from HarvestPlus; Fig.2: from HarvestPlus; Fig 3: Frank N. Foode , mascot of the Biofortified Blog, poses with some orange maize that has been bred to express very high levels of beta-carotene. Follow Frank’s adventures on twitter: @franknfoode Photo by Anastasia Bodnar.


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