Malnutrition is a general term that indicates a lack of some or all nutritional elements necessary for human health (Medline Plus Medical Encyclopedia).

There are two basic types of malnutrition. The first and most important is protein-energy malnutrition--the lack of enough protein (from meat and other sources) and food that provides energy (measured in calories) which all of the basic food groups provide. This is the type of malnutrition that is referred to when world hunger is discussed. The second type of malnutrition, also very important, is micronutrient (vitamin and mineral) deficiency. This is not the type of malnutrition that is referred to when world hunger is discussed, though it is certainly very important.

[Recently there has also been a move to include obesity as a third form of malnutrition. Considering obesity as malnutrition expands the previous usual meaning of the term which referred to poor nutrition due to lack of food inputs.2 It is poor nutrition, but it is certainly not typically due to a lack of calories, but rather too many (although poor food choices, often due to poverty, are part of the problem). Obesity will not be considered here, although obesity is certainly a health problem and is increasingly considered as a type of malnutrition.]

Protein-energy malnutrition (PEM) is the most lethal form of malnutrition/hunger. It is basically a lack of calories and protein. Food is converted into energy by humans, and the energy contained in food is measured by calories. Protein is necessary for key body functions including provision of essential amino acids and development and maintenance of muscles.

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Number of hungry people in the world

925 million hungry people in 2010

No one really knows how many people are malnourished. The statistic most frequently cited is that of the United Nations Food and Agriculture Organization, which measures 'undernutrition'. The most recent estimate, released in October 2010 by FAO, says that 925 million people are undernourished. As the figure below shows, the number of hungry people has increased since 1995-97, though the number is down from last year. The increase has been due to three factors: 1) neglect of agriculture relevant to very poor people by governments and international agencies; 2) the current worldwide economic crisis, and 3) the significant increase of food prices in the last several years which has been devastating to those with only a few dollars a day to spend. 925 million people is 13.6 percent of the estimated world population of 6.8 billion. Nearly all of the undernourished are in developing countries.

Number of hungry people, 1969-2010

Source: FAO

In round numbers there are 7 billion people in the world. Thus, with an estimated 925 million hungry people in the world, 13.1 percent, or almost 1 in 7 people are hungry.

The FAO estimate is based on statistical aggregates. It looks at a country's income level and income distribution and uses this information to estimate how many people receive such a low level of income that they are malnourished. It is not an estimate based on seeing to what extent actual people are malnourished and projecting from there (as would be done by survey sampling). [It has been argued that the FAO approach is not sufficient to give accurate estimates of malnutrition (Poverty and Undernutrition p. 298 by Peter Svedberg).]

Undernutrition is a relatively new concept, but is increasingly used. It should be taken as basically equivalent to malnutrition. (It should be said as an aside, that the idea of undernourishment, its relationship to malnutrition, and the reasons for its emergence as a concept is not clear to Hunger Notes.)

Children are the most visible victims of undernutrition. Children who are poorly nourished suffer up to 160 days of illness each year. Poor nutrition plays a role in at least half of the 10.9 million child deaths each year--five million deaths. Undernutrition magnifies the effect of every disease, including measles and malaria. The estimated proportions of deaths in which undernutrition is an underlying cause are roughly similar for diarrhea (61%), malaria (57%), pneumonia (52%), and measles (45%) (Black 2003, Bryce 2005). Malnutrition can also be caused by diseases, such as the diseases that cause diarrhea, by reducing the body's ability to convert food into usable nutrients.

According to the most recent estimate that Hunger Notes could find, malnutrition, as measured by stunting, affects 32.5 percent of children in developing countries--one of three (de Onis 2000). Geographically, more than 70 percent of malnourished children live in Asia, 26 percent in Africa and 4 percent in Latin America and the Caribbean. In many cases, their plight began even before birth with a malnourished mother. Under-nutrition among pregnant women in developing countries leads to 1 out of 6 infants born with low birth weight. This is not only a risk factor for neonatal deaths, but also causes learning disabilities, mental, retardation, poor health, blindness and premature death.

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Does the world produce enough food to feed everyone?

The world produces enough food to feed everyone. World agriculture produces 17 percent more calories per person today than it did 30 years ago, despite a 70 percent population increase. This is enough to provide everyone in the world with at least 2,720 kilocalories (kcal) per person per day (FAO 2002, p.9). The principal problem is that many people in the world do not have sufficient land to grow, or income to purchase, enough food.

What are the causes of hunger?

What are the causes of hunger is a fundamental question, with varied answers.

Poverty is the principal cause of hunger. The causes of poverty include poor people's lack of resources, an extremely unequal income distribution in the world and within specific countries, conflict, and hunger itself. As of 2008 (2005 statistics), the World Bank has estimated that there were an estimated 1,345 million poor people in developing countries who live on $1.25 a day or less.3 This compares to the later FAO estimate of 1.02 billion undernourished people. Extreme poverty remains an alarming problem in the world’s developing regions, despite some progress that reduced "dollar--now $1.25-- a day" poverty from (an estimated) 1900 million people in 1981, a reduction of 29 percent over the period. Progress in poverty reduction has been concentrated in Asia, and especially, East Asia, with the major improvement occurring in China. In Sub-Saharan Africa, the number of people in extreme poverty has increased. The statement that 'poverty is the principal cause of hunger' is, though correct, unsatisfying. Why then are (so many) people poor? The next section summarizes Hunger Notes answer.

Harmful economic systems are the principal cause of poverty and hunger. Hunger Notes believes that the principal underlying cause of poverty and hunger is the ordinary operation of the economic and political systems in the world. Essentially control over resources and income is based on military, political and economic power that typically ends up in the hands of a minority, who live well, while those at the bottom barely survive, if they do. We have described the operation of this system in more detail in our special section on Harmful economic systems.

Conflict as a cause of hunger and poverty. At the end of 2005, the global number of refugees was at its lowest level in almost a quarter of a century. Despite some large-scale repatriation movements, the last three years have witnessed a significant increase in refugee numbers, due primarily to the violence taking place in Iraq and Somalia. By the end of 2008, the total number of refugees under UNHCR’s mandate exceeded 10 million. The number of conflict-induced internally displaced persons (IDPs) reached some 26 million worldwide at the end of the year . Providing exact figures on the number of stateless people is extremely difficult But, important, (relatively) visible though it is, and anguishing for those involved conflict is less important as poverty (and its causes) as a cause of hunger. (Using the statistics above 1.02 billion people suffer from chronic hunger while 36 million people are displaced [UNHCR 2008])

Hunger is also a cause of poverty, and thus of hunger. By causing poor health, low levels of energy, and even mental impairment, hunger can lead to even greater poverty by reducing people's ability to work and learn, thus leading to even greater hunger.

Climate change Climate change is increasingly viewed as a current and future cause of hunger and poverty. Increasing drought, flooding, and changing climatic patterns requiring a shift in crops and farming practices that may not be easily accomplished are three key issues. See the Hunger Notes special report: Hunger, the environment, and climate change for further information, especially articles in the section: Climate change, global warming and the effect on poor people such as Global warming causes 300,000 deaths a year, study says and Could food shortages bring down civilization?

Progress in reducing the number of hungry people

The target set at the 1996 World Food Summit was to halve the number of undernourished people by 2015 from their number in 1990-92. (FAO uses three year averages in its calculation of undernourished people.) The (estimated) number of undernourished people in developing countries was 824 million in 1990-92. In 2009, the number had climbed to 1.02 billion people. The WFS goal is a global goal adopted by the nations of the world; the present outcome indicates how marginal the efforts were in face of the real need.

So, overall, the world is not making progress toward the world food summit goal, although there has been progress in Asia, and in Latin America and the Caribbean.

Micronutrients

Quite a few trace elements or micronutrients--vitamins and minerals--are important for health. 1 out of 3 people in developing countries are affected by vitamin and mineral deficiencies, according to the World Health Organization. Three, perhaps the most important in terms of health consequences for poor people in developing countries, are:

Vitamin A Vitamin A deficiency can cause night blindness and reduces the body's resistance to disease. In children Vitamin A deficiency can also cause growth retardation. Between 100 and 140 million children are vitamin A deficient. An estimated 250,000 to 500 000 vitamin A-deficient children become blind every year, half of them dying within 12 months of losing their sight. (World Health Organization)

Iron Iron deficiency is a principal cause of anemia. Two billion people—over 30 percent of the world’s population—are anemic, mainly due to iron deficiency, and, in developing countries, frequently exacerbated by malaria and worm infections. For children, health consequences include premature birth, low birth weight, infections, and elevated risk of death. Later, physical and cognitive development are impaired, resulting in lowered school performance. For pregnant women, anemia contributes to 20 percent of all maternal deaths (World Health Organization).

Iodine Iodine deficiency disorders (IDD) jeopardize children’s mental health– often their very lives. Serious iodine deficiency during pregnancy may result in stillbirths, abortions and congenital abnormalities such as cretinism, a grave, irreversible form of mental retardation that affects people living in iodine-deficient areas of Africa and Asia. IDD also causes mental impairment that lowers intellectual prowess at home, at school, and at work. IDD affects over 740 million people, 13 percent of the world’s population. Fifty million people have some degree of mental impairment caused by IDD (World Health Organization).