Food supply is the total amount of food available to all the world’s people. No one can live without food. As a result, the supply of food has always ranked among humanity’s chief concerns. The food supply depends mainly on the world’s farmers. Farmers raise the crops and livestock that provide most of our food. As the world’s population has grown, so too has the demand for food. Farmers and other food producers have faced a major challenge in meeting this demand.
The availability of food can vary from year to year and from country to country. World food production has increased steadily since 1970. Modern farmers produce enough food to feed the world’s population. Yet hundreds of millions of people suffer from hunger and malnutrition. These people lack food security—that is, reliable access to sufficient food and nutrition. Producing enough food is not sufficient on its own to ensure food security. In most places, food is a commodity that is bought and sold on the market. Thus, even if enough food is produced to feed everyone, many people may lack the money to afford it. Problems with the distribution of food can also undermine food security.
Without food security, people and countries remain more vulnerable to food crises. A food crisis may be caused by a sudden disruption to food production. Such a disruption may result from widespread damage to crops from such natural causes as drought, flooding, and insect infestation. Human activities, such as warfare, can also lead to food crises. In addition, food crises may result from changes in market prices or trade patterns
Experts use the term food sovereignty to describe the degree to which local groups control their own supply of food, apart from global market trends. Movements for increased food sovereignty have become popular in less developed regions such as Latin America, Africa, and Asia. Food sovereignty involves not only controlling the overall supply of food but also preserving local traditions of food and diet.
This article discusses basic food needs, major sources of food, and conditions that affect the food supply. It also discusses efforts to improve the food supply and food security. For more information, see the articles Agriculture , Farm and farming , Food , and Nutrition .
Basic human food needs
Food contains a number of nutrients (nourishing substances) that humans need to live. Food supplies energy that human bodies use for daily activities. This energy can be measured in units called calories. Food also supplies human bodies with a nutrient called protein. The body uses protein for energy and also for building, repairing, and maintaining its cells and tissues. In addition, the body depends on small amounts of micronutrients, such as vitamins and minerals, to maintain health. No single food contains all the nutrients the body needs. Thus, food security depends on access to a varied and balanced supply of foods.
More than 800 million people worldwide suffer from hunger or malnutrition. Most of these people live in less developed countries, particularly in sub-Saharan Africa (the part of Africa south of the Sahara) and South Asia. Young children and women—especially pregnant or nursing women—are particularly vulnerable to hunger and malnutrition. The rural poor and people who belong to ethnic or racial minorities within their countries are also vulnerable to these problems.
Calories.
Two types of nutrients—carbohydrates and fats—normally provide most of the calories in the human diet. Carbohydrates include starches and sugars. Cereal grains, the most widely grown type of food, are rich in carbohydrates. The main cereal grains are barley, corn, millet, oats, rice, rye, sorghum, and wheat.
The number of calories a person needs each day depends on the person’s sex, age, body build, and degree of physical activity. Larger and more active people require more calories. Children and young people who are still growing need more calories than their size would indicate.
Daily calorie consumption (intake) in the poorest countries is below 2,000—far fewer than most active people require. In some developed countries, daily calorie consumption averages over 3,300—far more than most people need. The body stores most excess calories as fat.
Protein,
like carbohydrates and fat, can provide energy. But protein also serves as an important building block for cells. Animal-based sources of protein include dairy products, eggs, fish, and meat. The best plant-based sources of protein are legumes or pulses, including beans and peas. Cereal grains also supply some protein.
Proteins consist of smaller units called amino acids. Most animal proteins supply all the amino acids the body needs. A given plant source may lack certain amino acids. But certain combinations of plants, such as beans and rice, supply all the necessary amino acids.
Daily protein consumption in some developed countries averages 100 or more grams per day. In the poorest countries, people consume less than 50 grams of protein per day on average. Because many people in these countries have too few calories in their diet, much of the protein they consume is used to meet their energy needs, leaving less protein to build and maintain body cells.
Major sources of food
Certain crops, called staples, provide much of the world’s nutrition and so are grown in huge quantities. Cereal grains serve as the most important staple crop. In some regions, such crops as potatoes and yams are staples.
Cereal grains
rank as the world’s most important food source. Worldwide, they supply about half the calories and much of the protein that people consume.
Almost all the grain grown in less developed countries is food grain—that is, grain consumed directly by people as food. The people may simply cook the grain as a main dish. Or they may use it to make bread, noodles, or some other food. People in developed countries also consume grain directly. But they also use much of it as feed grain, which is fed to livestock. People consume this grain indirectly in the form of such livestock products as meat, eggs, and dairy.
Certain grains used chiefly as feed in some countries are used chiefly as food in other countries. For example, most of the corn grown in the United States becomes livestock feed. But in some African and Latin American countries, corn serves as an important food grain.
Other crops.
Soybeans and other legumes rank second only to rice as a source of food in many Asian countries. Potatoes serve as a staple food in parts of Europe and South America. People in some tropical areas rely largely on such local foods as bananas, cassava (a starchy root), and sweet potatoes or yams.
Livestock and seafood
are the main sources of animal protein. On a worldwide basis, meat, eggs, and dairy products supply about 80 percent of the animal protein in the human diet. Seafood supplies about 20 percent of the animal protein people consume. In certain countries, however, fish provide a much larger percentage of the animal protein. Such countries include Japan, Norway, and the Philippines. Many people worry that the worldwide fish supply is being drastically diminished by overfishing. As a result, international commissions and some national governments are actively seeking to conserve fishing areas.
Conditions that affect the food supply
The food supply consists mainly of food produced during the current year. But it also includes reserves, also called stocks, left over from previous years. Food reserves are necessary to help prevent shortages after poor farming years. To build up reserves, the countries of the world overall must produce more food in a year than they consume. But few countries produce a surplus. The United States produces by far the largest surplus. Argentina, Australia, Brazil, Canada, and New Zealand also regularly produce a food surplus.
Most countries produce some food and then import additional supplies. Most developed countries that do not produce sufficient food can afford to import the extra supplies they need. The United Kingdom and Japan are examples of such countries. But less developed countries may lack enough money to import all the food they need, especially during food crises. For example, during global economic turmoil in 2007 and 2008, prices of staple grains and other foods rose significantly. The increase made it difficult for less developed countries to import a sufficient amount of food.
The amount of food produced by a country depends partly on the country’s agricultural resources, such as land and water. No country has an unlimited supply of these resources. The worldwide food supply thus depends on limited agricultural resources and the ever-increasing demand for food. The supply of food within a certain country can also be affected by problems of distribution, national agricultural policy, and the economy.
Limited agricultural resources.
Farming requires resources, especially land, water, energy, and fertilizer. Land serves as the chief agricultural resource. Land used for growing crops must be level and fertile. But most of the world’s good cropland is already in use. Most of the unused farmable land lies in remote areas, far from markets and transportation.
All crops require water to grow—some more than others—but rainfall is distributed unevenly over Earth’s surface. Some farmers can depend on rainfall for all the water they need. In other areas, the rainfall is too light or uncertain. Farmers in these areas must use irrigation water, if it is available. The supply of irrigation water is limited, and farmers in some countries use nearly all the available supply.
Many farmers depend heavily on energy resources—particularly petroleum fuels—to operate tractors, irrigation pumps, and other equipment. They use fertilizers to enrich the soil. Most fertilizers are nitrogen-based and are made from natural gas. But supplies of petroleum and natural gas are limited. Thus, farms will someday need other sources of energy and nitrogen fertilizers. Meanwhile, the energy needs of farmers have greatly increased. Since 1950, the amount of energy used to produce a ton of grain has more than doubled. In some countries, the energy used to produce fertilizer exceeds that used to power tractors. In every country, rising prices for energy and fertilizer add to the cost of food.
Increased use of agricultural resources can help farmers produce more food. But it can also cause environmental problems. For example, increased use of nitrogen fertilizers sometimes creates a build-up of nitrogen compounds in the soil. Rain water eventually washes these compounds into rivers and streams. There the compounds contribute to an overgrowth of algae, serving as a major source of water pollution.
Increased demand for food
chiefly results from the growth in world population. To a lesser extent, it also comes from rising standards of living. Higher living standards enable people to afford both bigger meals and higher quality foods.
The effect of population growth.
Experts measure a country’s food supply by the amount of food per capita. The per capita amount is how much food would be available for each person if the food were distributed equally among all. The food supply thus depends not only on the total amount of food but also on the number of people who must be fed.
World food production is increasing at a rate slightly higher than world population growth. The changes vary from place to place, however. In Europe and many parts of Asia, people have relatively few children, and food production has outpaced population growth. But in other regions, especially Africa, population continues to grow faster than food production.
In an attempt to avoid disastrous food shortages, many less developed countries have promoted birth control programs to curb population growth (see Birth control ). But such programs often lack significant influence and are sometimes actively opposed for cultural or religious reasons.
The effect of higher living standards.
As people improve their living standards, especially through increased personal income, they usually eat more food. In time, they also generally begin to eat more expensive foods, particularly more meat. Greater meat consumption typically requires an increase in the amount of grain used for livestock feed. For this reason, many countries with a high standard of living also have a high per capita consumption of grain.
In developed countries, people may directly consume about 200 to 300 pounds (90 to 135 kilograms) of grain per person annually. In many such countries, several times that amount of grain per person is fed to livestock each year. People consume this grain indirectly in the form of meat, eggs, and dairy products. In addition, grain is also used to make alcohol. Total per capita grain consumption in some developed countries can thus reach about 2,000 pounds (900 kilograms) annually. Total per capita grain consumption in less developed countries, on the other hand, often averages about 400 to 600 pounds (180 to 270 kilograms) a year. In the poorest countries, per capita grain consumption can be significantly lower. Most of this grain is consumed directly.
Distribution problems.
Less developed countries are more likely to lack adequate forms of infrastructure, such as modern facilities for the transportation and storage of food. In many cases, food supplies cannot be delivered immediately where they are needed. They also cannot be safely stored to await shipment. As a result, large quantities of food spoil or are eaten by rodents and insects. Thus, food waste in such countries is likely to occur between farmers and food retailers (sellers).
In developed countries, food waste more often occurs among retailers and consumers. Such countries have adequate transportation and storage infrastructures. But retailers and consumers there throw away much food through strictly following expiration dates. Much prepared food in homes and in restaurants also ends up being thrown away.
National agricultural policies.
Many countries fund agricultural research and farmer education. Such policies can greatly increase the food supply.
Many nations also influence the food supply by actively managing the agricultural industry. For much of the 1900’s, many countries—including the United States—adopted a policy of supply management. The primary goal of the policy was to maintain a stable supply of certain agricultural products, while at the same time avoiding too great a surplus. Supply management policy relied on income subsidies to farmers. These subsidies, often money paid directly to farmers, guaranteed high prices for agricultural products, even if the market value of such products was low. Supply management also relied on production controls, measures that limit the acreage of a commodity that can be harvested.
One effect of supply management policy was to help stabilize a country’s economy for agriculture, limiting price fluctuations and protecting the overall food supply. The policy, however, also encouraged farmers to overproduce some commodities—such as wheat—for which they received subsidies. The surplus that resulted was often sent to less developed countries as food aid. As a result, some less developed countries became more dependent on imported food aid and invested less in their own food systems.
The economy and agriculture.
Since the 1980’s and 1990’s, most countries have weakened or eliminated supply management policy. While the United States continues to provide subsidies to farmers, for example, it has eliminated production controls. The market economy now exerts a stronger influence in agriculture. This influence has helped make agriculture less stable. Annual prices fluctuate (vary up and down) more markedly than they did during the era of supply management.
Increased fluctuation in prices affects both farmers and consumers, especially in less developed countries. Fluctuating annual prices, especially sharp declines in price, can hurt farmers’ incomes. For example, coffee prices were once kept artificially high through a worldwide supply management policy called the International Coffee Agreement. When the agreement collapsed in 1989, world coffee prices dropped by about 50 percent in a few years. The price collapse led to a “coffee crisis” in which coffee farmers saw their incomes drop dramatically, and many of them could no longer support themselves. Coffee prices have remained extremely unpredictable since the collapse of the agreement.
Sharp increases in food prices can make it difficult for consumers to afford adequate food. In developed countries, most people spend only a small fraction of their income on food and so can better absorb price increases. In less developed countries, on the other hand, consumers may spend more than half of their incomes on food. They have little additional income to accommodate a large spike in staple prices. From mid-2007 to early 2008, for example, wheat prices increased by more than 200 percent. The jump harmed the ability of poorer households to support themselves.
Increasing the food supply
Most increases in food supply result from greater output by farms. Farm output can be increased in two main ways: by developing new farmland and by making existing farmland more productive. Two other methods of increasing the food supply involve reducing the demand for feed grain and developing new sources of food.
Developing new farmland
is difficult and costly. The largest areas of land that could be developed for farming are in sub-Saharan Africa and in the Amazon River Basin of South America. Dense forests cover much of this land. The tropical soil and climate are also not ideal for many kinds of farming.
Nations often establish expensive programs to encourage farmers to clear land and plant crops. However, forest soils lack many important plant nutrients and are quickly depleted by farming. Scientists are working to develop farming methods that preserve forest soils.
In addition, the expansion of farmlands can threaten tropical rain forests and other valuable natural areas. Scientists fear that continued destruction of forests and other habitats will lead to the extinction of thousands of species of plants and animals.
Making farmland more productive.
Farmers have two main methods of making the land more productive. They may increase their use of irrigation, energy, and fertilizer. Or they may use improved varieties of grains and livestock. Improved varieties produce higher crop yields and larger amounts of livestock products. Farmers in developed countries have used both methods for many years. In the 1960’s, farmers in some less developed countries also adopted both methods to increase their production of wheat and rice. This effort proved so successful that it has become known as the Green Revolution.
The development of high-yield varieties of rice and wheat made the Green Revolution possible. But the revolution also required greater use of irrigation water, energy, and fertilizer. Many farmers took water from wells, installing electric or diesel-powered pumps to bring it to the surface. To get the highest yields, farmers had to enrich the soil with fertilizers. During the 1960’s and 1970’s, these methods helped such countries as India and Mexico more than double their wheat production.
The Green Revolution can continue to make farmland more productive. If farmers in the tropics have enough water, fertilizer, and other essential resources, for example, they can grow multiple crops a year on the same land. But the Green Revolution’s ability to increase the food supply is limited. Many farmers in less developed countries cannot afford the additional resources that the Green Revolution requires. In any case, greater use of these resources makes land more productive only to a point. Farmers in the 2010’s used roughly 10 times as much fertilizer as they did in 1950. However, grain yields in the 2010’s were only about three times as large—and the rates of increase are slowing.
Much agricultural research is being done to further increase farmland productivity. For example, scientists are working to develop varieties of grain that not only produce higher yields but also have other improved characteristics. Such grain might supply more complete nutrition, make more efficient use of water and fertilizer, and grow with better resistance to insects and disease. However, it is difficult to develop a plant variety with so many different positive characteristics. The necessary research therefore takes much time and money.
In some instances, less developed countries have benefited from the introduction of large-scale agriculture. This practice has often been promoted as a way to generate income through export of crops. However, small-scale farming can make more efficient use of land than large-scale farming does. Many experts now encourage small-scale farming over large-scale farming to increase food supplies for local people in less developed countries.
Reducing the demand for feed grain
would increase the amount of calories and plant-based protein available for human consumption. This increase would occur because livestock consume more calories and protein than they produce. Grain-fed beef cattle are especially inefficient in this respect. By some measures, it takes roughly 10 pounds (4.5 kilograms) of grain to produce only 1 pound (0.5 kilogram) of boneless beef. But 10 pounds of grain supplies several times as many calories as does 1 pound of beef, and more protein as well.
In the past, almost all beef cattle grazed on grass and other forage up to the time of slaughter. But since the mid-1900’s, cattle-fattening establishments called feed lots have become popular in the United States, Canada, and other developed countries. A feed lot fattens cattle on grain. Today, most U.S. beef cattle are fattened on feed lots, consuming enormous quantities of grain, especially corn. The demand for feed grain would lessen if the cattle industry returned to raising cattle chiefly on forage. But relying on forage would not produce enough beef to satisfy U.S. demand. In addition, many people in the United States prefer the flavor of beef from grain-fed cattle. The demand for feed grain would also decline if people in developed countries ate less meat.
Developing new sources of food.
Such oilseed crops as coconuts, cottonseed, peanuts, and soybeans can all serve as valuable sources of protein. Soybeans have an especially high protein content. Soy-based foods, such as tofu, have long been important in Asia, where soybeans originated. But with this exception, none of these oilseed crops ranks as a major, widespread food source. Instead, farmers grow the crops mainly for their oils. These oils are used to make such products as margarine, salad dressing, and many kinds of prepared dishes and snacks. The protein, however, remains in the meal, the part of the seed that is left after the oil has been removed. Most of the meal is used for livestock feed.
Since the mid-1900’s, food scientists have been working to make the protein in soybean meal available for human consumption. They have developed a variety of inexpensive, specially flavored foods from soybean meal. Some of these products have been successfully marketed in various parts of the world, often as meat and dairy substitutes. Food scientists are also working to convert other oilseed crop meal into foods that will have a broad appeal. Such crops are widely grown in the tropics. They could provide millions of people in less developed countries with inexpensive protein.
Scientists and manufacturers of food products have also developed methods of enriching food. For example, manufacturers often add micronutrients to bread and to other grain products to improve nutritional value.
Food supply programs
Various organizations sponsor programs to increase and improve the world’s food supply. The chief international organizations include two United Nations (UN) agencies: the Food and Agriculture Organization (FAO) and the World Bank. The World Food Council, a group of food experts appointed by the United Nations, helps coordinate the work of the various international organizations. Many developed nations have set up their own agencies to help increase the world’s food supply.
Private groups sponsor a number of important food supply programs. For example, the Rockefeller Foundation has long been one of the biggest contributors to agricultural research in less developed countries. The foundation is a philanthropic organization founded in the United States by the Rockefeller family.
Technical and financial programs
work to expand farm output in less developed countries. The Food and Agriculture Organization sponsors the chief technical assistance programs. These programs seek mainly to train farmers in modern agricultural methods. The United Nations Development Programme also sponsors technical aid programs.
Most financial help for agriculture in less developed countries takes the form of low-interest loans. The World Bank and regional banks associated with the World Bank provide most of these loans. In 1976, the United Nations established the International Fund for Agricultural Development to obtain additional loan funds from prosperous UN member nations. The United States offers technical aid and loans chiefly through its Agency for International Development.
Food aid programs
provide shipments of food to countries that need emergency aid. Industrialized countries in Europe and the Americas, along with Japan, contribute most of this aid. The United States ranks as the largest contributor. Most of the assistance given by the United States is administered through the federal government’s Food for Peace program. The World Food Programme, sponsored by the UN and the FAO, channels donations from individual countries to nations in need of aid. The Food Assistance Convention, an international treaty signed by many developed countries, directs grain donations and other forms of assistance from individual countries to nations in need. Many private charitable organizations also supply food aid.
Research programs.
Scientific research programs seek to increase both the quantity and the quality of the food supply. Researchers are constantly trying to develop cereal grains that can provide higher amounts of protein while also giving high enough yields.
Research scientists are also seeking ways to conserve agricultural resources. Some of this research is aimed at developing varieties of grain that make more efficient use of water and fertilizer. Animal scientists are conducting similar experiments to develop varieties of cattle that produce more meat for the same amount of feed. International organizations and national governments have placed controls on the harvesting of many types of fish to prevent excessive depletion of stocks. In addition, more of the world’s fish supply is being produced through aquaculture, the controlled farming of fish and aquatic plants.
Many research projects take place at agricultural research institutes sponsored by the Consultative Group on International Agricultural Research (CGIAR). CGIAR is funded by a mix of governments, international agencies, and private foundations. These institutes have been established in less developed countries. Each specializes in a particular type of research. In Mexico, for example, the International Center for the Improvement of Maize and Wheat focuses on producing improved varieties of corn, wheat, and other grains. Some of the institutes, such as the International Institute of Tropical Agriculture, in Nigeria, focus on improving agriculture specifically in places with tropical climates.
Food reserves.
The world’s food reserves consist of the individual reserves of the major exporting countries. Each country administers its own reserves. Some food from these reserves is supplied to nations in need of aid through programs conducted separately by each government. Another part of the reserves is pledged by governments to international organizations, such as the World Food Programme.
