| Malnutrition | |
|---|---|
| Classification and external resources | |
The orange ribbon—an awareness ribbon for malnutrition. |
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| ICD-9 | 263.9 |
| eMedicine | ped/1360 |
| MeSH | D044342 |
Malnutrition is the condition that results from taking an unbalanced diet in which certain nutrients are lacking, in excess (too high an intake), or in the wrong proportions.[1][2]
A number of different nutrition disorders may arise, depending on which nutrients are under or overabundant in the diet.
The World Health Organization cites malnutrition as the greatest single threat to the world's public health.[3] Improving nutrition is widely regarded as the most effective form of aid.[3][4] Emergency measures include providing deficient micronutrients through fortified sachet powders, such as peanut butter, or directly through supplements.[5][6] The famine relief model increasingly used by aid groups calls for giving cash or cash vouchers to the hungry to pay local farmers instead of buying food from donor countries, often required by law, as it wastes money on transport costs.[7][8]
There are various methods used to gauge the degree of malnutrition, including the Gomez Classification. This classifies as 1st, 2nd or 3rd degree malnutrition according to the percentage of normal body weight a person is.
Long term measures include investing in modern agriculture in places that lack them, such as fertilizers and irrigation, which largely eradicated hunger in the developed world.[9] However, World Bank strictures restrict government subsidies for farmers and the spread of fertilizer use is hampered by some environmental groups.[10][11]
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According to Jean Ziegler(the United Nations Special Rapporteur on the Right to Food for 2000 to March 2008), mortality due to malnutrition accounted for 58% of the total mortality in 2006: "In the world, approximately 62 million people, all causes of death combined, die each year. One in twelve people worldwide is malnourished.[12] In 2006, more than 36 million died of hunger or diseases due to deficiencies in micronutrients".[13]
According to the World Health Organization, malnutrition is by far the biggest contributor to child mortality, present in half of all cases.[3] Six million children die of hunger every year.[14] Underweight births and inter-uterine growth restrictions cause 2.2 million child deaths a year. Poor or non-existent breastfeeding causes another 1.4 million. Other deficiencies, such as lack of vitamin A or zinc, for example, account for 1 million. Malnutrition in the first two years is irreversible. Malnourished children grow up with worse health and lower educational achievements. Their own children also tend to be smaller. Malnutrition was previously seen as something that exacerbates the problems of diseases as measles, pneumonia and diarrhea. But malnutrition actually causes diseases as well, and can be fatal in its own right.[3]
Malnutrition increases the risk of infection and infectious disease; for example, it is a major risk factor in the onset of active tuberculosis.[15] In communities or areas that lack access to safe drinking water, these additional health risks present a critical problem. Lower energy and impaired function of the brain also represent the downward spiral of malnutrition as victims are less able to perform the tasks they need to in order to acquire food, earn an income, or gain an education.
Malnutrition, in the form of iodine deficiency, is "the most common preventable cause of mental impairment worldwide."[17] Even moderate iodine deficiency, especially in pregnant women and infants, lowers intelligence by 10 to 15 I.Q. points, shaving incalculable potential off a nation’s development.[17] The most visible and severe effects — disabling goiters, cretinism and dwarfism — affect a tiny minority, usually in mountain villages. But 16 percent of the world’s people have at least mild goiter, a swollen thyroid gland in the neck.[17]
Research indicates that improving the awareness of nutritious meal choices and establishing long-term habits of healthy eating has a positive effect on a cognitive and spatial memory capacity, potentially increasing a student's potential to process and retain academic information.
Some organizations have begun working with teachers, policymakers, and managed foodservice contractors to mandate improved nutritional content and increased nutritional resources in school cafeterias from primary to university level institutions. Health and nutrition have been proven to have close links with overall educational success.[18] Currently less than 10% of American college students report that they eat the recommended five servings of fruit and vegetables daily.[19] Better nutrition has been shown to have an impact on both cognitive and spatial memory performance; a study showed those with higher blood sugar levels performed better on certain memory tests.[20] In another study, those who consumed yogurt performed better on thinking tasks when compared to those who consumed caffeine free diet soda or confections.[21] Nutritional deficiencies have been shown to have a negative effect on learning behavior in mice as far back as 1951.[22]
The "nutrition-learning nexus" demonstrates the correlation between diet and learning and has application in a higher education setting.
There is limited research available that directly links a student's Grade Point Average (G.P.A.) to their overall nutritional health. Additional substantive data is needed to prove that overall intellectual health is closely linked to a person's diet, rather than just another correlation fallacy.
Nutritional supplement treatment may be appropriate for major depression, bipolar disorder, schizophrenia, and obsessive compulsive disorder, the four most common mental disorders in developed countries.[28] Supplements that have been studied most for mood elevation and stabilization include eicosapentaenoic acid and docosahexaenoic acid (each of which are an omega-3 fatty acid contained in fish oil, but not in flaxseed oil), vitamin B12, folic acid, and inositol.
Cancer is now common in developing countries. According a study by the International Agency for Research on Cancer, "In the developing world, cancers of the liver, stomach and esophagus were more common, often linked to consumption of carcinogenic preserved foods, such as smoked or salted food, and parasitic infections that attack organs." Lung cancer rates are rising rapidly in poorer nations because of increased use of tobacco. Developed countries "tended to have cancers linked to affluence or a 'Western lifestyle' — cancers of the colon, rectum, breast and prostate — that can be caused by obesity, lack of exercise, diet and age."[29]
Several lines of evidence indicate lifestyle-induced hyperinsulinemia and reduced insulin function (i.e. insulin resistance) as a decisive factor in many disease states. For example, hyperinsulinemia and insulin resistance are strongly linked to chronic inflammation, which in turn is strongly linked to a variety of adverse developments such as arterial microinjuries and clot formation (i.e. heart disease) and exaggerated cell division (i.e. cancer). Hyperinsulinemia and insulin resistance (the so-called metabolic syndrome) are characterized by a combination of abdominal obesity, elevated blood sugar, elevated blood pressure, elevated blood triglycerides, and reduced HDL cholesterol. The negative impact of hyperinsulinemia on prostaglandin PGE1/PGE2 balance may be significant.
The state of obesity clearly contributes to insulin resistance, which in turn can cause type 2 diabetes. Virtually all obese and most type 2 diabetic individuals have marked insulin resistance. Although the association between overweight and insulin resistance is clear, the exact (likely multifarious) causes of insulin resistance remain less clear. Importantly, it has been demonstrated that appropriate exercise, more regular food intake and reducing glycemic load (see below) all can reverse insulin resistance in overweight individuals (and thereby lower blood sugar levels in those who have type 2 diabetes).
Obesity can unfavourably alter hormonal and metabolic status via resistance to the hormone leptin, and a vicious cycle may occur in which insulin/leptin resistance and obesity aggravate one another. The vicious cycle is putatively fuelled by continuously high insulin/leptin stimulation and fat storage, as a result of high intake of strongly insulin/leptin stimulating foods and energy. Both insulin and leptin normally function as satiety signals to the hypothalamus in the brain; however, insulin/leptin resistance may reduce this signal and therefore allow continued overfeeding despite large body fat stores. In addition, reduced leptin signalling to the brain may reduce leptin's normal effect to maintain an appropriately high metabolic rate.
There is a debate about how and to what extent different dietary factors— such as intake of processed carbohydrates, total protein, fat, and carbohydrate intake, intake of saturated and trans fatty acids, and low intake of vitamins/minerals—contribute to the development of insulin and leptin resistance. In any case, analogous to the way modern man-made pollution may potentially overwhelm the environment's ability to maintain homeostasis, the recent explosive introduction of high glycemic index and processed foods into the human diet may potentially overwhelm the body's ability to maintain homeostasis and health (as evidenced by the metabolic syndrome epidemic).
Excess water intake, without replenishment of sodium and potassium salts, leads to hyponatremia, which can further lead to water intoxication at more dangerous levels. A well-publicized case occurred in 2007, when Jennifer Strange died while participating in a water-drinking contest.[30] More usually, the condition occurs in long-distance endurance events (such as marathon or triathlon competition and training) and causes gradual mental dulling, headache, drowsiness, weakness, and confusion; extreme cases may result in coma, convulsions, and death. The primary damage comes from swelling of the brain, caused by increased osmosis as blood salinity decreases. Effective fluid replacement techniques include Water aid stations during running/cycling races, trainers providing water during team games such as Soccer and devices such as Camel Baks which can provide water for a person without making it too hard to drink the water.
Although a lot of the focus regarding malnutrition centers around undernourishment, overeating is also a form of malnutrition. Overeating is much more common in the United States,[31] where for the majority of people, access to food is not an issue. The issue in these developed countries is choosing the right kind of food. Fast food is consumed more per capita in the United States than in any other country. The reason for this mass consumption of food is the affordability and accessibility. Oftentimes the fast food, low in cost and nutrition, are high in calories and heavily promoted. When these eating habits are combined with increasingly urbanized, automated, and more sedentary lifestyles, it becomes clear why gaining weight is difficult to avoid.[32]
However, overeating is also a problem in countries where hunger and poverty persist. In China, consumption of high-fat foods has increased while consumption of rice and other goods has decreased.[33] Overeating leads to many diseases, such as heart disease and diabetes, that may result in death.
Major causes of malnutrition include poverty and food prices, dietary practices and agricultural productivity, with many individual cases being a mixture of several factors. Malnutrition can also be a consequence of other health issues such as diarrheal disease or chronic illness,[34] especially the HIV/AIDS pandemic[35] Clinical malnutrition, such as in cachexia, is a major burden also in developed countries.
As much as food shortages may be a contributing factor to malnutrition in countries with lack of technology, the FAO (Food and Agriculture Organization) has estimated that eighty percent of malnourished children living in the developing world live in countries that produce food surpluses.[33] The economist Amartya Sen observed that, in recent decades, famine has always a problem of food distribution and/or poverty, as there has been sufficient food to feed the whole population of the world. He states that malnutrition and famine were more related to problems of food distribution and purchasing power.[36]
It is argued that commodity speculators are increasing the cost of food. As the real estate bubble in the United States was collapsing, it is said that trillions of dollars moved to invest in food and primary commodities, causing the 2007–2008 food price crisis.[37]
The use of biofuels as a replacement for traditional fuels may leave less supply of food for nutrition and raises the price of food.[38] The United Nations special rapporteur on the right to food, Jean Ziegler proposes that agricultural waste, such as corn cobs and banana leaves, rather than crops themselves be used as fuel.[39]
A lack of breastfeeding can lead to malnutrition in infants and children. Possible reasons for the lack in the developing world may be that the average family thinks bottle feeding is better.[40] The WHO says mothers abandon it because they do not know how to get their baby to latch on properly or suffer pain and discomfort.[41]
Deriving too much of one's diet from a single source, such as eating almost exclusively corn or rice, can cause malnutrition. This may either be from a lack of education about proper nutrition, or from only having access to a single food source.
Many tend to think malnutrition only in terms of hunger, however, overeating is also a contributing factor as well. Many parts of the world have access to a surplus of non-nutritious food, in addition to increased sedentary lifestyles. In turn, this has created a universal epidemic of obesity. Yale psychologist Kelly Brownell calls this a "toxic food environment” where fat and sugar laden foods have taken precedent over healthy nutritious foods. Not only does obesity occur in developed countries, problems are also occurring in developing countries in areas where income is on the rise.[33]
Food shortages can be caused by a lack of farming skills such as crop rotation, or by a lack of technology or resources needed for the higher yields found in modern agriculture, such as nitrogen fertilizers, pesticides and irrigation. As a result of widespread poverty, farmers cannot afford or governments cannot provide the technology. The World Bank and some wealthy donor countries also press nations that depend on aid to cut or eliminate subsidized agricultural inputs such as fertilizer, in the name of free market policies even as the United States and Europe extensively subsidized their own farmers.[10][42] Many, if not most, farmers cannot afford fertilizer at market prices, leading to low agricultural production and wages and high, unaffordable food prices.[10]
Reasons for the unavailability of fertilizer include moves to stop supplying fertilizer on environmental grounds, cited as the obstacle to feeding Africa by the Green Revolution pioneer Norman Borlaug.[11]
There are a number of potential disruptions to global food supply that could cause widespread malnutrition.
Climate change is of great importance to food security. With 95% of all malnourished peoples living in the relatively stable climate region of the sub-tropics and tropics. According to the latest IPCC reports, temperature increases in these regions are "very likely."[43] Even small changes in temperatures can lead to increased frequency of extreme weather conditions.[43] Many of these have great impact on agricultural production and hence nutrition. For example, the 1998–2001 central Asian drought brought about an 80% livestock loss and 50% reduction in wheat and barley crops in Iran.[44] Similar figures were present in other nations. An increase in extreme weather such as drought in regions such as Sub-Saharan would have even greater consequences in terms of malnutrition. Even without an increase of extreme weather events, a simple increase in temperature reduces the productiveness of many crop species, also decreasing food security in these regions.[43][45]
Colony collapse disorder is a phenomenon where bees are dying in large numbers.[46] Since many agricultural crops worldwide are pollinated by bees, this represents a serious threat to the supply of food.[47]
An epidemic of stem rust on wheat caused by race Ug99 is currently spreading across Africa and into Asia and, it is feared, could wipe out more than 80% of the world’s wheat crops.[48][49]
Fighting malnutrition, mostly through fortifying foods with micronutrients (vitamins and minerals), improves lives at a lower cost and shorter time than other forms of aid, according to the World Bank.[50] The Copenhagen Consensus, which look at a variety of development proposals, ranked micronutrient supplements as number one.[4][51] However, roughly $300m of aid goes to basic nutrition each year, less than $2 for each child below two in the 20 worst affected countries.[3] In contrast, HIV/AIDS, which causes fewer deaths than child malnutrition, received $2.2 billion—$67 per person with HIV in all countries.[3]
Micronutrients can be obtained through fortifying foods.[4] Fortifying foods such as peanut butter sachets (see Plumpy'Nut) and Spirulina have revolutionized emergency feeding in humanitarian emergencies because they can be eaten directly from the packet, do not require refrigeration or mixing with scarce clean water, can be stored for years and, vitally, can be absorbed by extremely ill children.[5] The United Nations World Food Conference of 1974 declared Spirulina as 'the best food for the future' and its ready harvest every 24 hours make it a potent tool to eradicate malnutrition. Additionally, supplements, such as Vitamin A capsules or Zinc tablets to cure diarrhea in children, are used.[6]
There is a growing realization among aid groups that giving cash or cash vouchers instead of food is a cheaper, faster, and more efficient way to deliver help to the hungry, particularly in areas where food is available but unaffordable.[7] The UN's World Food Program, the biggest non-governmental distributor of food, announced that it will begin distributing cash and vouchers instead of food in some areas, which Josette Sheeran, the WFP's executive director, described as a "revolution" in food aid.[7][8] The aid agency Concern Worldwide is piloting a method through a mobile phone operator, Safaricom, which runs a money transfer program that allows cash to be sent from one part of the country to another.[7]
However, for people in a drought living a long way from and with limited access to markets, delivering food may be the most appropriate way to help.[7] Fred Cuny stated that "the chances of saving lives at the outset of a relief operation are greatly reduced when food is imported. By the time it arrives in the country and gets to people, many will have died."[52] US Law, which requires buying food at home rather than where the hungry live, is inefficient because approximately half of what is spent goes for transport.[51] Fred Cuny further pointed out "studies of every recent famine have shown that food was available in-country — though not always in the immediate food deficit area" and "even though by local standards the prices are too high for the poor to purchase it, it would usually be cheaper for a donor to buy the hoarded food at the inflated price than to import it from abroad."[53] Ethiopia has been pioneering a program that has now become part of the World Bank's prescribed recipe for coping with a food crisis and had been seen by aid organizations as a model of how to best help hungry nations. Through the country's main food assistance program, the Productive Safety Net Program, Ethiopia has been giving rural residents who are chronically short of food, a chance to work for food or cash. Foreign aid organizations like the World Food Program were then able to buy food locally from surplus areas to distribute in areas with a shortage of food.[54] Not only has Ethiopia been pioneering a program but Brazil has also established a recycling program for organic waste that benefits farmers, urban poor, and the city in general. City residents separate organic waste from their garbage, bag it, and then exchange it for fresh fruit and vegetables from local farmers. As a result, this reduces its countries waste and the urban poor get a steady supply of nutritious food.[32]
The effort to bring modern agricultural techniques found in the West, such as nitrogen fertilizers and pesticides, to Asia, called the Green Revolution, resulted in decreases in malnutrition similar to those seen earlier in Western nations. This was possible because of existing infrastructure and institutions that are in short supply in Africa, such as a system of roads or public seed companies that made seeds available.[55] Investments in agriculture, such as subsidized fertilizers and seeds, increases food harvest and reduces food prices.[10][56] For example, in the case of Malawi, almost five million of its 13 million people used to need emergency food aid. However, after the government changed policy and subsidies for fertilizer and seed were introduced against World Bank strictures, farmers produced record-breaking corn harvests as production leaped to 3.4 million in 2007 from 1.2 million in 2005, making Malawi a major food exporter.[10] This lowered food prices and increased wages for farm workers.[10] Proponents for investing in agriculture include Jeffrey Sachs, who has championed the idea that wealthy countries should invest in fertilizer and seed for Africa’s farmers.[9][10]
Breast-feeding education helps. Breastfeeding in the first two years and exclusive breastfeeding in the first six months could save 1.3 million children’s lives.[57] In the longer term, firms are trying to fortify everyday foods with micronutrients that can be sold to consumers such as wheat flour for Beladi bread in Egypt or fish sauce in Vietnam and the iodization of salt.[5]
Restricting population size is a proposed solution. Thomas Malthus argued that population growth could be controlled by natural disasters and voluntary limits through “moral restraint.”[58] Robert Chapman suggests that an intervention through government policies is a necessary ingredient of curtailing global population growth.[59] However, there are many who believe that the world has more than enough resources to sustain its population. Instead, these theorists point to unequal distribution of resources and under- or unutilized arable land as the cause for malnutrition problems.[60][61] For example, Amaryta Sen advocates that, “no matter how a famine is caused, methods of breaking it call for a large supply of food in the public distribution system. This applies not only to organizing rationing and control, but also to undertaking work programmes and other methods of increasing purchasing power for those hit by shifts in exchange entitlements in a general inflationary situation.”[36] One suggested policy framework to resolve access issues is termed food sovereignty, the right of peoples to define their own food, agriculture, livestock, and fisheries systems in contrast to having food largely subjected to international market forces. Food First is one of the primary think tanks working to build support for food sovereignty. Neoliberals advocate for an increasing role of the free market. Another possible long term solution would be to increase access to health facilities to rural parts of the world. These facilities could monitor undernourished children, act as supplemental food distribution centers, and provide education on dietary needs. These types of facilities have already proven very successful in countries such as Peru and Ghana.[62][63] New technology in agricultural production also has great potential to combat under nutrition.[64] By improving agricultural yields, farmers could reduce poverty by increasing income as well as open up area for diversification of crops for household use. The World Bank itself claims to be part of the solution to malnutrition, asserting that the best way for countries to succeed in breaking the cycle of poverty and malnutrition is to build export-led economies that will give them the financial means to buy foodstuffs on the world market.
When aiming to prevent rather than treat overeating, which is also a form of malnutrition, starting in the school environment would be the perfect place as this is where the education children receive today will help them choose healthier foods during childhood, as well as into adulthood. As seen in Singapore, if we increase nutrition in school lunch programs and physical activity for children and teachers, obesity can be reduced by almost 30–50%.[33]
There were 925 million undernourished people in the world in 2010, an increase of 80 million since 1990,[66][67] despite the fact that the world already produces enough food to feed everyone — 6 billion people — and could feed the double — 12 billion people.[68]
| Year | 1990 | 1995 | 2005 | 2008 |
|---|---|---|---|---|
| Undernourished people in the world (millions)[69] | 843 | 788 | 848 | 923 |
| Year | 1970 | 1980 | 1990 | 2005 | 2007 |
|---|---|---|---|---|---|
| Percentage of people in the developing world who are undernourished[70][71] | 37 % | 28 % | 20 % | 16 % | 17 % |
Number of undernourished people (million) in 2001–2003, according to the FAO, the following countries had 5 million or more undernourished people [1]:
| Country | Number of Undernourished (million) |
|---|---|
| India | 217.05 |
| China | 154.0 |
| Bangladesh | 43.45 |
| Democratic Republic of Congo | 37.0 |
| Pakistan | 35.2 |
| Ethiopia | 31.5 |
| Tanzania | 16.1 |
| Philippines | 15.2 |
| Brazil | 14.4 |
| Indonesia | 13.8 |
| Vietnam | 13.8 |
| Thailand | 13.4 |
| Nigeria | 11.5 |
| Kenya | 9.7 |
| Sudan | 8.8 |
| Mozambique | 8.3 |
| North Korea | 7.9 |
| Yemen | 7.1 |
| Madagascar | 7.1 |
| Colombia | 5.9 |
| Zimbabwe | 5.7 |
| Mexico | 5.1 |
| Zambia | 5.1 |
| Angola | 5.0 |
Note: This table measures "undernourishment", as defined by FAO, and represents the number of people consuming (on average for years 2001 to 2003) less than the minimum amount of food energy (measured in kilocalories per capita per day) necessary for the average person to stay in good health while performing light physical activity. It is a conservative indicator that does not take into account the extra needs of people performing extraneous physical activity, nor seasonal variations in food consumption or other sources of variability such as inter-individual differences in energy requirements.
Malnutrition and undernourishment are cumulative or average situations, and not the work of a single day's food intake (or lack thereof). This table does not represent the number of people who "went to bed hungry today."
Various scales of analysis also have to be considered in order to determine the sociopolitical causes of malnutrition. For example, the population of a community may be at risk if it lacks health-related services, but on a smaller scale certain households or individuals may be at even higher risk due to differences in income levels, access to land, or levels of education.[72] Also within the household, there may be differences in levels of malnutrition between men and women, and these differences have been shown to vary significantly from one region to another with problem areas showing relative deprivation of women.[73] Children and the elderly tend to be especially susceptible. Approximately 27 percent of children under 5 in developing world are malnourished, and in these developing countries, malnutrition claims about half of the 10 million deaths each year of children under 5.
Malnutrition rates in Iraq had risen from 19% before the US-led invasion to a national average of 28% four years later.[74]
According to the Global Hunger Index, South Asia has the highest child malnutrition rate of world's regions.[75] India contributes to about 5.6 million child deaths every year, more than half the world's total.[76] The 2006 report mentioned that "the low status of women in South Asian countries and their lack of nutritional knowledge are important determinants of high prevalence of underweight children in the region" and was concerned that South Asia has "inadequate feeding and caring practices for young children".[76]
Half of children in India are underweight,[77] one of the highest rates in the world and nearly double the rate of Sub-Saharan Africa.[78]
Research on overcoming persistent under-nutrition published by the Institute of Development Studies, argues that the co-existence of India as an 'economic powerhouse' and home to one-third of the world's under-nourished children reflects a failure of the governance of nutrition: "A poor capacity to deliver the right services at the right time to the right populations, an inability to respond to citizens' needs and weak accountability are all features of weak nutrition governance."[79] The research suggests that to make under-nutrition history in India the governance of nutrition needs to be strengthened and new research needs to focus on the politics and governance of nutrition. At the current rate of progress the MDG1 target for nutrition will only be reached in 2042 with severe consequences for human wellbeing and economic growth.[79]
Childhood malnutrition is generally thought of as being limited to developing countries, but although most malnutrition occurs there, it is also an ongoing presence in developed nations. For example, in the United States of America, one out of every six children is at risk of hunger. A study, based on 2005–2007 data from the U.S. Census Bureau and the Agriculture Department, shows that an estimated 3.5 million children under the age of five are at risk of hunger in the United States.[80] In developed countries, this persistent hunger problem is not due to lack of food or food programs, but is largely due to an underutilization of existing programs designed to address the issue, such as food stamps or school meals. Many citizens of rich countries such as the United States of America attach stigmas to food programs or otherwise discourage their use. In the USA, only 60% of those eligible for the food stamp program actually receive benefits.[81] The U.S. Department of Agriculture reported that in 2003, only 1 out of 200 U.S. households with children became so severely food insecure that any of the children went hungry even once during the year. A substantially larger proportion of these same households (3.8 percent) had adult members who were hungry at least one day during the year because of their households' inability to afford enough food.[82]
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