The United Nations Food and Agriculture Organization (FAO) reports that world food prices increased dramatically in the first half of 2008, and then over the second half, fell by nearly 50% ( Figure 1 ). FAO cautions that the recent decline in food prices does not indicate that "the world's food problems have been fixed, neither in the short-run nor with a view to the longer-term challenges." Those who were most affected by high food prices earlier in the year remain vulnerable for a number of reasons including higher priced food inputs (e.g., fuel, fertilizers, and seeds) that limit the amount of food that poor farmers can produce (both for their own consumption and for sale); poorly functioning infrastructure and roads that inhibit small-scale farmers' access to larger markets; low investments in agriculture that remain low; and climate change that forebodes decreased crop output in some areas, particularly in Africa. In the first half of 2008, higher food prices and poor food supplies contributed to social unrest, deepened poverty, and worsened food insecurity, which led to declines in health conditions among millions of people. In July 2008, FAO identified 34 countries that needed help to feed their populations (see Appendix A ). A combination of factors cause food crises, including conflict; natural disasters; cultural and gender dynamics; urbanization; greater use of bioenergy; and changes in incomes, climatic patterns, food prices, and food production. This report does not explore the causes of food crises, but analyzes how high food prices, food insecurity, and hunger impact the health of people in countries where food prices increased dramatically. In a 2006 report, FAO estimated that 848 million people in the world were undernourished. In September 2008, it reported that a number of factors, primarily high food prices, forced 75 million more people into hunger, bringing the total number of undernourished to 923 million in 2007 ( Table 1 and Figure 2 ). About 90% of the newly hungry were African or Asian. The World Food Program (WFP) contends that even if food prices had not spiked, some 10 million people would die each year from hunger or hunger-related diseases, about half of whom would be children. In addition to those deaths, about 2 billion people are blinded are otherwise afflicted by vitamin and mineral deficiencies. About 90% of the 10 million annual hunger-related deaths occur among people who are chronically hungry—those who do not consume enough food for sustained periods of time and are most likely to be malnourished as a result. Malnourished people are more susceptible to a host of diseases and malnourished children are more likely to experience stunted growth, impaired learning, and difficulty in resisting and recovering from illness. Similarly, malnourished adults are often less responsive to medication, less productive, and in the case of women, experience more complications during pregnancy. Acute hunger—accounting for about 10% of hunger-related deaths—is of shorter duration and usually occurs during natural disasters, famines, or conflict. Those who are acutely hungry are more easily identified, as they are often concentrated in a certain area. Drought-induced hunger, for example, might affect a specific population contained in one region; or people fleeing conflict might be concentrated in a refugee camp. The chronically hungry are more widely dispersed and account for about 90% of the undernourished. Higher food prices endanger the acutely hungry, because they lessen the amount of food that can be bought and provided through assistance programs. The chronically hungry will most likely attempt to cope with higher food prices by withdrawing their children from school and forcing them to beg or find employment, decrease their intake of nutritious foods, sell their assets, and ultimately engage in behavior that worsens their health and plunges them deeper into poverty. Although more people suffer from chronic hunger, press coverage and U.S. foreign assistance largely focus on those who are acutely hungry. In 2007, about 80% of U.S. food aid was targeted at the acutely hungry ( Table 3 ). Beyond food aid, U.S. policy concerns related to food insecurity include broader global health implications. Those who are most affected by higher food prices and disrupted food supplies are the impoverished. "In 2005, about 40% of the world's 6.5 billion people lived in poverty, defined by a poverty line of $2.00 a day in 2005 prices which is the average poverty line found among developing countries. The World Bank estimates that in 2005, 1.4 billion people lived below the average poverty line found in the poorest developing countries ($1.25 per day) and a further 1.2 billion lived between $1.25 and $2.00 per day." Poor people struggling to feed themselves and their families tend to survive off of diets that are nutritionally deficient. Once food prices rise, the poor tend to decrease their intake of nutritious foods, such as fruits and vegetables and replace them with food that is more filling but less expensive and nutritious, like roots. These actions make the poor more likely to become malnourished. Undernourished people, especially children, are more likely to contract and succumb to disease. FAO asserts that the vast majority of the nearly 10 million children who die each year "would not die if their bodies and immune systems had not been weakened by hunger and malnutrition." According to UNICEF, under-nutrition is the underlying cause of up to half of all deaths among children under five years and about 20% of all maternal deaths. Analysis of 10 community-based studies of children under age five found that children who are mildly underweight are about twice as likely to die of infectious diseases as children who are better nourished; and for those who are moderately to severely underweight, the risk of death is five to eight times higher. The studies also indicated that 45% of children who died after contracting measles were malnourished, as were more than 60% of children who died after the onset of severe diarrhea. Some experts are concerned that the impoverished, who were struggling to feed, clothe, and educate their children before prices began to rise, might decrease spending on health and education. Another group of analysts contend that families struggling to feed themselves will be less likely to take a sick child to the clinic or a pregnant woman to the hospital, which could increase maternal and child mortality rates. Health experts expect that when food prices are high, poor parents will remove their children from school to spend their limited funds on food that has become more expensive rather than on school fees. Not only does this interrupt the children's education, but it also increases the likelihood that the children might become further malnourished, because they will not be present to receive school feedings. While global food prices have moderated recently, they remain higher than they were earlier in the decade. According to the World Bank, high food prices are pushing poor people deeper into poverty across the globe, particularly in countries that import most of their foods and have limited capacity to cushion the shock of high prices. Estimates vary, but there is broad agreement among many groups that millions of people were pushed into poverty by food price increases. These people are widely characterized as "the new faces of hunger." Some experts contend that many more may become impoverished and undernourished because forecasts indicate food supplies may remain insufficient and prices may stay higher than the averages of the past decade —though projections indicate they will ease over the next 10 years ( Table 2 ). Food price increases in 2007 and the first half of 2008 did not equally benefit farmers. According to FAO, industrialized countries benefitted the most from food price spikes and accounted for the bulk of increased food production in 2007 and 2008. In developing countries, food production increased minimally in 2007 and barely in 2008. The majority of poor farmers in developing countries did not benefit from the food price spikes because the higher prices of inputs like fertilizers, seeds, and energy prohibited them from farming. Poor subsistence farmers were particularly burdened by higher input prices because they could not benefit from any potential marketable surplus. Other factors that hindered food production in developing countries included export taxes and controls. Even as food prices decline, poor farmers remain vulnerable to poverty and hunger. Lower demand for food, brought on in part by decelerated global economic growth, has led to lower food prices. Reduced prices for food means that farmers collect less for crop output. Poor rural inhabitants are increasingly moving to urban areas in search of better economic opportunities—though natural population growth is the predominant cause of urban population growth, rather than rural-to-urban migration. Rural-to-urban population shifts leave fewer workers to harvest crops, potentially further exacerbating the problem of inconsistent food supplies. When poor farmers move to urban areas, they usually do so with few resources and often seek housing in informal settlements or slums that hold a number of health dangers. Slum dwellings are usually characterized by conditions that are overcrowded and have limited or no access to electricity, running water, sewage systems, roads, and other urban services, such as health clinics. Consequently, diseases proliferate in slum environments. Without access to electricity, slum dwellers "rely on traditional biomass fuels for cooking and heating, typically in open fires or low-efficiency stoves with inadequate venting, [which] leads to significant air pollution and causes severe health implications—including acute respiratory infections such as pneumonia, which kill almost 4 million people a year." Poor management of sewerage and solid waste leaves people susceptible to a range of diseases, including cholera, typhoid fever, malaria, and diarrhea—particularly after periods of flooding or heavy rainfall. People living in overcrowded slum conditions are also vulnerable to diseases like tuberculosis (TB), meningitis, and polio. Urban slum growth is outpacing urban growth in planned areas by a wide margin, particularly in developing countries.