Ten percent of children, or at least 155 million youngsters worldwide, are overweight or obese, a leading health expert said Wednesday, citing new evidence of the extent of the problem.

“We need urgent action. The time for action is now,” said Professor Ricardo Uauy, chair of public health nutrition at the London School of Hygiene and Tropical Medicine.

Uauy, an editor of a new report on childhood obesity, called for a global strategy to stem the rising number of obese children everywhere.

“We are facing an epidemic in children,” he told Reuters. “We thought obesity was a problem for adults-it is a global problem in children and it is going to get worse before it gets better.”

Although it is most severe in the United States, where the prevalence of obese children between 5 and 17 is about 10 percent and more than 30 percent are overweight, numbers are rising in Europe, the Middle East and in the Asia/Pacific region, according to the report by the London-based International Obesity Task Force (IOTF).

Ten to 20 percent of children in northern Europe are overweight, while further south in Europe the numbers increase to 20-35 percent.

What was once a health problem for the industrialized world with its high calorie foods, labor-saving devices and dwindling levels of physical activity has now spread to developing countries.

In South Africa, about 25 percent of girls from 13-19 are overweight or obese-a number approaching U.S. levels, according to the report.

“These figures are extremely high, especially figures emerging from developing countries where we thought malnutrition was a problem,” Uauy added “Now we are seeing that stunted children become obese as soon as they start getting the regular diet and physical inactivity of other countries.”

SOCIAL TRENDS

In the report, Uauy and his colleagues identified social trends that have contributed to the problem and called for the World Health Organization (WHO) to help developing countries organize strategies to prevent childhood obesity.

It would include efforts to improve maternal nutrition and to promote breastfeeding, to encourage schools to teach children how to eat better, to provide clear nutrition information to consumers and safe play facilities in local neighborhoods.

Changes in diet, a decrease in physical activity and too much time spent in front of computer or television screens have been blamed for the growing number of overweight children.

Obesity increases a child’s risk of developing type 2 diabetes and, later in life, of developing heart disease, stroke and certain types of cancer.

“A global strategy means keeping children active at school and at play and making sure that foods that are energy-dense be limited. We cannot have high-energy food so that a child in 15 minutes will eat 80 percent of his calories for the day,” Uauy added.

“In some countries, over the past decade, the figure has tripled. I think it is never too late but it is time we start getting serious about doing something about it.”