* Most stunted-growth kids in Asia, Africa; India hit hard
* Rate of problem has fallen in Africa, Asia
* Tough for states with undernourished kids to end poverty
By Louis Charbonneau
UNITED NATIONS, Nov 11 (Reuters) - Nearly 200 million children in developing countries suffer from stunted growth and health problems due to poor nutrition in their early years, the U.N. children's foundation UNICEF said on Wednesday.
However, the percentage of children with retarded growth in Asia fell to 30 percent last year from 44 percent in 1990, and in Africa to 34 percent from 38 percent over the same period, UNICEF said in a report.
Despite a decline in the rate of the problem, 195 million children in developing countries under 5 years old have stunted growth due to poor nutrition during the critical period between their conception and second birthdays, UNICEF said.
Undernourished children often have poor physical health and slower mental development. When the problem is widespread, as in India and Afghanistan, it undermines those countries' ability to improve their economies and eradicate poverty.
"Undernutrition steals a child's strength and makes illnesses that the body might otherwise fight off far more dangerous," UNICEF Executive Director Ann Veneman said in a statement.
"More than one third of children who die from pneumonia, diarrhea and other illnesses could have survived had they not been undernourished," she said.
More than 90 percent of the developing world's children facing stunted growth live in Africa and Asia, the report said. A third of them -- roughly 60.8 million -- are in India.
UNICEF said that countries with the highest prevalence of stunted growth among children under the age of five include Afghanistan (59 percent), Yemen (58 percent), Guatemala and East Timor (both 54 percent), Democratic Republic of the Congo (46 percent) and North Korea (45 percent).
India, the world's second most-populous country, continues to have a high rate of children under 5 years old suffering from retarded growth, though it fell from around 52 percent in 1992-1993 to 43 percent in 2005-2006, UNICEF said.
Veneman told reporters on a conference call that roughly 8.8 million children are dying every year from largely preventable causes and poor nutrition is a contributing factor in more than a third of those deaths.
She added that the issue of access to proper nutrition for impoverished children and pregnant and breastfeeding mothers was related to the larger issue of poor food security in a world where some 1 billion people are hungry or malnourished.
The 1,000 days from conception until a child's second birthday are the most important for growth and development, the report said. Insufficient nutrition during this period can permanently harm the body's ability to ward off and overcome diseases and damage a child's social and mental development.
Stunted growth, UNICEF said, can rarely be corrected. However, Veneman said it can be prevented and programs to improve access to iodized salt and vitamin A supplements in Africa and Asia have improved the situation in some countries -- and led to a reduction in infant and child mortality. (Editing by Eric Beech)