Researchers at the University of Nottingham have precisely mapped the diversity of nutrients in different grains. They did fieldwork in Ethiopia and Malawi. Their research was recently published in the scientific journal nature.
Worldwide, one in four people suffer from “hidden hunger”, which means that they get enough calories, but are deficient in one or more micronutrients. These are nutrients that are found in small amounts in food, such as vitamins and minerals. Hidden hunger can lead to learning problems as children grow and is not easily treatable, so that someone can suffer lifelong consequences.
The United Nations (UN) has set a goal to end world hunger by 2030. It is therefore useful to predict where a deficiency of certain micronutrients may occur. For example, measures to combat hunger can be carried out in a targeted manner, for example by enriching crops with minerals in some places or by providing nutritional supplements to the population.
The researchers analyzed mineral concentrations in crops and in soils at more than 3,000 sites in Ethiopia and Malawi. These are generally poor areas, where most people only eat plant foods. They get most of their micronutrients from grains. The researchers analyzed four major minerals in different types of grains: calcium, iron, iodine and selenium.
In Malawi, where maize is mainly grown, the risks of deficiencies in this micronutrient appear to be greater. Corn contained the lowest concentration of all four minerals. For example, corn can meet only 3 percent of the recommended amount of calcium. In Ethiopia, wheat and teff, a type of grain with long stalks and small grains, provide 25 percent of the RDI.
But the concentrations did not only differ between crops. There was also a large variation in the concentration of minerals within crops. For example, the concentration of iron in teff in a spot in Ethiopia can be twice as high as 150 km. This is mainly due to the amount of minerals in the soil, although this is not all. Minerals in the soil can bind to other substances, so that plants can absorb them less.
Marc Artes, professor of plant genetics at Wageningen University, says the research makes a significant contribution to eliminating hidden hunger. The amount of micronutrients varies greatly at the local level. Now that that’s been identified, we know better where some of the interventions make sense. For example, you can give farmers targeted access to specific fertilizers that are rich in minerals, so that their crops have more nutrients needed in that location.”