The humanitarian department of the U.N. mission in the Caribbean nation of 10 million people said in its monthly bulletin that a spike in malnutrition has been recorded in some areas since October. At least one in five households faces a serious food deficit and acute malnutrition despite efforts to reduce hunger, the study said.
Malnutrition is worst in Haiti's far western corner in the administrative department of Grande-Anse, the U.N. said. There have also been reports of acute malnutrition in southeastern Haiti.
Widespread flooding damaged crops in the country's south when Hurricane Sandy and Tropical Storm Isaac brushed Haiti last year.
The U.N. said that more than more than 1.5 million of Haiti's people are at risk of malnutrition because of crops lost in the hurricane. As much as 90 percent of Haiti's harvest season, much of it in the south, was destroyed in Sandy's floods.