Every eighth person in the world goes to bed hungry every day. According to estimates by the Food and Agriculture Organization (FAO), which belongs to the United Nations (UN), this is 821 million people. Most of the hungry are at home in Africa. About three-quarters live in rural areas – where food is cultivated. Theoretically, enough food would be available if the distribution were fair and the only cause of hunger. According to the FAO, food production would have to increase by at least 60% by 2050 if the estimated 9 billion people living there were to be satisfied.
What is hunger?
The FAO defines hunger as when the daily energy intake over a prolonged period remains below the level required for a healthy body. The minimum food intake required is assessed by this UN organisation at approximately 1,800 calories per day. But hunger is not only the result of too few calories; it has various forms.
According to the German aid organisation World Hunger Relief (Welthungerhilfe), based in Bonn, there are three different types of hunger:
- Chronic hunger:
Constant or regular seasonal malnutrition, hich affects both the quantity and the quality of food.
- Acute hunger:
Severe malnutrition for a limited period, for example, as a result of natural disasters.
Lack of nutrition caused by an absence or insufficient amount of nutrients and/or vitamins.
Lack of micronutrients
For some time now, scientists, led by Professor Hans Konrad Biesalski of the University of Hohenheim, near Stuttgart, have been pointing out that malnutrition, which is also referred to as hidden or silent hunger, is a major problem. The three staple foods of rice, maize and wheat cover about 80% of the daily calorie requirements of one third of the world’s population, but they lack micronutrients such as vitamins, minerals, trace elements, essential fatty acids and amino acids.
of the daily calorie requirement cover the three staple foods rice, corn and wheat for one third of the world’s population.
Nutrition expert Prof Biesalski warns us not to see world hunger simply as an insufficient quantity of food. If malnutrition starts in the mother’s womb, this has a negative impact on the physical and mental development of a child. With increasing poverty, the hidden hunger of malnutrition is also becoming more common in highly developed countries like the USA and in Europe. People with little money to spend rely mainly on energy-rich or fatty foods. This results in poorer people becoming overweight – as paradoxical as this may seem at first sight, as a consequence of malnutrition.
Zinc deficiency in cereals
Professor Ismail Cakmak, of Sabanci University in Istanbul has taken up the cause of fighting against malnutrition by improving the diet of people by adding more micronutrients, which also include trace elements. When this agricultural scientist discovered about twenty years ago in Anatolia that zinc deficiency was the cause of stunted growth in cereals, resulting in declining yields, this caused a minor sensation. Before that time, the link between the zinc-deficient soils of Anatolia and diseases in plants and humans had not been explained.
Although Prof Cakmak has been involved in the international Harvest Zinc Fertilizer Project since 2008, there is still much work to be done. Almost half of the world’s grain crops suffer from zinc deficiency. This results in smaller harvests with a lower zinc concentration in the grain, and consequently also in grain-based foods, as the 55-year-old explained at a conference of the Institute of Applied Plant Nutrition (IAPN), a collaboration project of the University of Göttingen in Germany and the German fertiliser producer K+S Kali. With the development of better fertilisation methods and the breeding of new varieties of crops which can absorb more zinc from the soil and store it in their grain, Prof Cakmak hopes that it will be possible to further improve the situation in Turkey and in developing and emerging countries.
Selenium: important but unknown
Less well known than zinc, the trace element selenium is found in humans in all our tissues and is a building block for about twenty types of proteins. It is also partly responsible for keeping our immune system healthy. Despite its important benefits, most people know nothing about it, even though selenium-enriched vegetables are sold in the UK. When the major retailer Waitrose offered selenium-enriched bread, consumers responded with less enthusiasm than had been hoped for. People simply did not realise what health benefits they might derive from this.
Not only people but also animals can be affected by selenium deficiency. This is a particular problem in the upland and hill farming areas of the UK, where the soils tend to have an even lower selenium status than in the lowlands. James Evans, a Shropshire beef and sheep farmer, started giving extra selenium to his livestock ten years ago, using rumen boluses that also contain cobalt and iodine. “We saw a huge difference in our breeding performance due to reduced numbers of retained cleansings and increasing fertility.”
Blood testing and forage analysis accurately tell farmers when their livestock are lacking in selenium. Vet Harriet Fuller, based in Herefordshire, says: “Farmers are generally providing adequate supplementation but we do still come across livestock where we diagnose selenium deficiency as the cause of infertility.” Ms Fuller favours boluses and drenches over mineral licks, but has also seen good results from fertiliser. “Boluses can last up to six months, covering the whole of the grazing period. Drenching might be best for lambs because they might not be on the farm long enough to warrant boluses. But mineral licks give uneven use: some will take a lot and some won’t take any.”
Iron: important for blood formation
Although iron occurs very commonly in nature – this element makes up 28% of the Earth’s mass and more than 5% of the Earth’s continental crust, many people only have very low levels of this trace element in their bodies. In Europe this is five to ten percent. Children and pregnant women are particularly at risk because they have a higher requirement for iron for their blood ormation. Iron is important for the synthesis of the red blood pigment (haemoglobin).
Although iron is prominently represented in nature, many people suffer from anaemia caused by iron deficiency. In Europe this is five to ten percent.
Iron deficiency can also occur in plants, even if this trace element is present in the soil in large quantities. The pH value of the soil is a critical factor in this. The more alkaline the soil is, the less iron will be received by plants. The iron occurring in a water-insoluble form in the soil must first be chemically modified by plants before it can be transported into their cells. The most commonly used strategy of plants affected by iron deficiency is to release protons through their roots into the soil to acidify it around their roots so that the iron will dissolve better. Grasses such as maize, wheat and rice have an additional strategy They emit so-called phytosiderophores which form a neutral complex with the iron, which is then drawn in by a specific transport system into the root cells.
Farmers have three main ways of combatting iron deficiency in plants: Iron fertilisation around the leaves or roots of the plants, cultivation of suitable varieties or cultivation of mixed crops. According to the University of Minnesota in the USA, when oats are planted as a mixed culture, this will improve the iron supply for soya beans, because the oats prevent a surplus of nitrates and excessive dampness of the soil.
An integrated approach is essential
Farmers are at the beginning of the food chain. They have a responsibility for feeding the population. If, for example, they grow their crops on land which is poor in nutrients, the products can hardly be better than the soil they grew in, even if professional cultivation methods are applied. To prevent this from happening, consultants, researchers and industry are requested to support farmers. Politicians also must not remain idle, because important issues such as the nutrition of the population are the concern of a government which aims to ensure that all its citizens have access to food in sufficient quantities and of a good quality. Finally, the consumers themselves have responsibilities too. If eating habits lead to diet-related diseases, a rethink of these habits is required.