Questions & Answers
What is food
Food security is the ability of all people at all times to
access enough food for an active and healthy life. Three conditions
must be fulfilled to ensure food security: food must be available,
each person must have access to it, and the food utilized must
fulfill nutritional requirements.
- Availability. Global food security
requires sufficient food production to provide the world's people
with the amount of food they need to lead active and healthy lives.
On a national level, food can be produced domestically or imported.
Domestic production depends on the size of the area harvested and
the yields achieved and is heavily influenced by weather,
especially where irrigation is nonexistent. Imports depend on a
country's ability to finance them and are determined by export
earnings and international food prices. Domestic production and
import activity are affected by domestic policies and international
- Access. Access to food is mainly determined by
household income. Lack of access is therefore closely linked with
poverty. Where incomes are insufficient, transfer or food
assistance programs (such as feeding programs or food subsidies)
are a means to ensuring access to food.
- Utilization. Adequate food utilization is a
key component of food security. Access to safe water, good
sanitation, and basic health care make a difference in nutritional
well-being as they have an impact on the body's ability to utilize
consumed foods. Inadequate knowledge of basic nutritional facts may
also prevent the best use of available food.
is food security assessed?
The ERS food security model projects food consumption and access
in 77 developing countries-37 in Sub-Saharan Africa, 4 in North
Africa, 11 in Latin America and the Caribbean, and 23 in Asia.
Commodity coverage in the model includes grains, root crops, and a
group called "other." The three commodity groups in total account
for 100 percent of all calories consumed in the study countries.
The projections are based on the most recently available 3-year
average of data and go out 10 years. Projections of food gaps for
the countries are based on differences between consumption targets
and estimates of food availability, which is domestic food supply
(production plus commercial imports) minus nonfood use. The
estimated food gaps (
nutrition gap, and
distribution gap) are used to evaluate food security of the
countries. Finally, based on projected population, the number of
people unable to meet their nutritional requirements is projected.
The methodology appendix in the Food Security Assessment
report describes the ERS approach in more detail.
What is the
World Food Summit?
In November 1996, world leaders assembled in Rome for the World
Food Summit to renew global commitment to the fight against
hunger. The United Nations Food and Agriculture Organization (FAO)
called the Summit in response to widespread undernutrition and
growing concern about the capacity of agriculture to meet future
food needs. Participants at the summit pledged by 2015 to reduce
the current number of hungry people by half.
FAO monitors efforts related to, and progress made
toward, meeting the goal of the World Food Summit.
Do ERS and the Food and
Agricultural Organization (FAO) use different measurements to
assess global food security?
To estimate the number of hungry people at the country level,
both ERS and FAO start by calculating the total amount of food
(food availability), taking into account food production, changes
in stocks, and imports as presented in the food balance sheet.
While FAO uses the number of calories as a unit of measurement, ERS
converts the calories to kilograms of grain equivalent.
To establish the number of people consuming less than the
nutritional requirement, it is first necessary to determine
consumption inequality due to inequality in purchasing power, i.e.,
access to food. FAO uses the estimate of per capita calorie
consumption of a country as its mean, while consumption/income
variance is estimated based on household survey data; it assumes
the consumption/income relationship to be log-normal. ERS estimates
of the consumption/income relationship are based on cross-country
data on per capita calorie consumption and per capita income, using
a semi-log regression functional form. ERS uses the estimated
coefficients to determine consumption/income elasticity for each
country. Income distribution data from the World Bank and
the estimated income elasticity coefficients are then used to
determine food consumption for each income group by country.
Once consumption inequality has been determined, a food level
has to be established below which people are considered
undernourished, i.e., suffer from hunger. FAO bases its cutoff food
level on a minimum calorie requirement of approximately 1,800
calories on average per capita per day for all countries. ERS uses
a higher level of roughly 2,100 calories per day as the average per
capita requirement for all countries. Once the threshold level is
established, the number of people living in hunger is
For further information, The Sixth World Food Survey, 1996,
Appendix 3, describes FAO methodology in detail. ERS publishes its
methodology in its annual Food Security Assessment
How does ERS research
on global food security differ from its research on food security
in the United States?
ERS research on global food security is based on measurable
components of food supply at the national level. In developing
countries, a large part of the population lives in poverty, which
is sometimes grave enough to cause death by starvation. National
food supplies are at times insufficient to feed the entire
population, even if the food available were distributed evenly
among all citizens. ERS research focuses on food availability and
access by using food production, trade, and macroeconomic data.
ERS research on
Food Security in the United States is based on household
surveys that capture householders' subjective evaluations of their
food security. In wealthier countries such as the United States,
where total food supplies are more than sufficient to feed the
entire population, famine or starvation is not a threat. However,
even in the United States, a large number of people are poor and
suffer from hunger due to inadequate incomes. Research on food
security tries to understand the true extent of the problem, as
well as the underlying causes. The focus is on access to food and
food utilization, while in the United States general food
availability is of little concern.