870 million people are chronically undernourished; almost two billion suffer from negative health consequences of micronutrient deficiencies.

FAO, 2012

Data from FAO, 2012

Extra facts

  • Most of the world’s undernourished live in low-income and middle-income countries; about 850 million people—almost 15 percent of the population—are estimated to be undernourished (FAO 2012).
  • More than 100 million children under the age of five are underweight, which has life-long effects on their development and achievements.
  • At least 2.5 million children die every year from malnutrition.
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Methods, caveats and issues

When comparing undernourishment figures from different sources, terminology needs to be taken into account. For example, “food insecurity”, “hunger” and “undernourishment” are often used interchangeably, but have different meanings.

The Food and Agriculture Organization of the United Nations (FAO), currently revising the methodology it uses to measure undernourishment, states in the 2012 publication “State of Food Insecurity in the World” that “further improvements and better data are needed to capture the effects of food price and other economic shocks.”

Defining undernourishment

“The State of Food Insecurity in the World” (FAO 2012) presents new estimates of the number and proportion of the world’s hungry people. These new numbers reflect technical improvements to the methodology FAO uses to derive its undernourishment indicator and data updates that go back to 1990. The estimates, for example, now incorporate the latest world population numbers and new, country-level information about minimum dietary energy requirements, dietary energy supplies and food losses at the retail distribution level.

Despite these data improvements, it is important to point out three limitations of these estimates.

  1. The prevalence of the undernourishment indicator is defined solely in terms of dietary energy availability and its distribution in the population and does not consider other aspects of nutrition.
  2. The indicator uses the energy requirements for minimum activity levels as a benchmark for dietary energy adequacy, though many poor and hungry people are likely to engage in higher activity levels, including arduous manual labor.
  3. The current methodology does not capture the impact of short-term price and other economic shocks, unless these are reflected in changes in long-term food consumption patterns.

These limitations, consistent with previous undernourishment definitions, underline the need to regard the FAO’s prevalence of undernourishment indicator as a conservative estimate of undernourishment. Further improvements, including the inclusion of a broader set of indicators, are necessary to reach a more holistic understanding of undernourishment and food insecurity. Additional indicators could include those that use a higher minimum energy requirement threshold corresponding to higher activity levels. These would imply very different levels and trends in undernourishment. For more on changes to the undernourishment indicator, see FAO 2012, p. 13-14.

Defining food security

The World Food Summit of 1996 defined food security as existing “when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life” (FAO 1996). In short, supply is not enough: food security is only attained when the right social, economic, physical and cultural conditions are also in place.

Based on these considerations, the FAO’s definition of food insecurity encompasses four key dimensions: food availability, stability, access and utilization (FAO 2006, 2008). These are described in more detail as follows:

  • Physical availability refers to the supply side of food security; it is determined by food production, stock levels, trade and other factors.
  • Economic and physical access to food is determined by such factors as household incomes and expenditure, markets and food prices.
  • Food utilization relates to the body’s ability to use food nutrients and includes the need for sufficient energy and nutrients, good care and feeding practices, safe food preparation, dietary diversity, food distribution within households and individual health status (which affects the ability to absorb nutrients).
  • Stability of food supply is affected by such factors as sudden economic, climatic or other shocks, or cyclical events such as seasonal food insecurity. Stability reflects the presence of the other three dimensions over time.

For more information on food security, see FAO (2008).

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  • [FAO] Food and Agriculture Organization of the United Nations. 1996. Declaration on world food security. World Food Summit. Rome: FAO.  (Available from http://www.fao.org/docrep/003/w3613e/w3613e00.htm)
  • [FAO] Food and Agriculture Organization of the United Nations. 2006. Food security: policy brief. Issue 2. FAO Agricultural and Development Economics Division. Rome: FAO.  (Available from http://www.fao.org/es/esa/)
  • [FAO] Food and Agriculture Organization of the United Nations.  2008. An introduction to the basic concepts of food security. Food Security Information for Action Practical Guides. EC - FAO Food Security Programme. Rome: FAO.  (Available from http://www.fao.org/docrep/013/al936e/al936e00.pdf)
  • [FAO] Food and Agriculture Organization of the United Nations.  2011. World hunger report 2011: High, volatile prices set to continue. FAO Media Centre. Rome: FAO.  (Available from http://www.fao.org/news/story/en/item/92495/icode/)
  • [FAO] Food and Agriculture Organization of the United Nations.  2011. The state of food insecurity in the world 2011: How does international price volatility affect domestic economies and food security? Rome: FAO. (Available from http://www.fao.org/publications/sofi-2011/en/)
  • [FAO] Food and Agriculture Organization of the United Nations.  2012. The state of food insecurity in the world 2012: Economic growth is necessary but not sufficient to accelerate reduction of hunger and malnutrition.   Rome: FAO.  (Available from http://www.fao.org/publications/sofi/en/)
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