More than half of the world's chronically undernourished children under the age of 5 live in South Asia, according to a U.N. report released Wednesday.
Chronically undernourished children are more likely to suffer serious infections and die from common illnesses such as diarrhea, measles, pneumonia and malaria, the report by the U.N. Children's Fund said.
Nutritional deficiencies damage a child's ability to learn, leave many stunted and lead to lower IQs, the report said.
More than 40 percent of young children are undernourished in Afghanistan, Nepal, India, Bangladesh and Pakistan, the five countries hit hardest by the problem, it said.
Nearly 83 million children under 5 in those countries do not get enough food, while in the rest of the world 72 million children are undernourished, the report said.
"The paradox of South Asia is that despite healthy levels of economic growth in many countries, chronic undernutrition remains persistently and unacceptably high," said UNICEF's regional director for South Asia, Daniel Toole.
Across South Asia, practices such as child marriage lead to many young teenagers getting pregnant. They are told to eat less for easier delivery, leaving them undernourished and causing them to give birth to underweight babies who have a harder time thriving, the report said.
Less than one-third of new mothers in these countries begin breast-feeding within the first three days of a child's life, it said.
Breast-feeding exclusively for at least six months can reduce mortality among children under 5 by 12 percent to 15 percent in developing countries, the report said.
"What is required now is strong leadership at the highest level," Toole said. "Without strategic investments in nutrition, economic growth alone cannot and will not make a lasting difference."