Sharp rise is seen in the number of overweight children in developing nations, says WHO. The number of overweight African children under five has tripled to 13.5 million in 20 years. Poor diet, low rates of breastfeeding and a sedentary life style are the main reasons for childhood obesity in developing countries.
Poor diet, low rates of breastfeeding and a sedentary lifestyle were largely to blame for the sharp rise in overweight children in developing nations, the World Health Organisation said.
In Africa the jump was from four million in 1990 to 13.5 million in 2010, an increase from four percent of the total under-five population to 8.5 percent, it said.
In Asia the corresponding gain over the same period was from 3.2 percent to 4.9 percent.
"The reason why children become overweight is because they are becoming more sedentary or less active and the food they have is exceeding their needs," said Francesco Branca, WHO's director of nutrition for health and development.
Children are given high energy food that is low in essential vitamins and minerals but heavy with sugar and fat, he noted.
"What we have seen in developing countries is that the offer of food is moving towards highly refined, industrial food which often have very high content of sugar and fat," Branca said.
The problem was compounded by a trend of lower breastfeeding rates, he said.
Poor nutrition among mothers also often resulted in newborns with a low birth weight of under 2.5 kilogrammes (5.51 pounds) who were vulnerable to becoming overweight later in life, Branca said.
"Often we have the combination of children who have low birth weight who become more easily children who are overweight," he said, adding "children with very low birth weight are less able to handle high energy density food."
The UN health agency issued in January a series of recommendations aimed at cutting child obesity, including a call on governments to ban junk food from schools and playgrounds.