A United Nations report says more than a billion people are going hungry as a result of the combination of higher food prices and the global economic crisis. World Food Day is on Friday.
The report by the Food and Agriculture Organization and the World Food Programme says the number of malnourished people in the world had been growing more slowly until the economic downturn.
The FAO says Asia and the Pacific have the largest number of hungry people - 642 million - followed by Sub-Saharan Africa with 265 million.
The FAO estimates that 1.02 billion people are undernourished worldwide in 2009 - the most since 1970.
The report, released in Rome, says the economic downturn has reduced foreign aid and investment in poorer countries and cut remittances from those working abroad.
The BBC reports the problem is compounded by food prices that are "still relatively high".
Both UN agencies urge international investment in agriculture and economic safety nets for poorer countries "despite financial constraints faced by governments around the world."