Overweight children are a growing problem in Africa and Asia

Driven by the growing availability of fatty, sugary foods and beverages in low- and middle-income countries, 41 million children age 5 and under are overweight or obese, a number expected to grow to more than 70 million children worldwide during the next decade, a new World Health Organization report says.

Between 1990 and 2014, rates of young children who are overweight or obese have surged to 6.1% from 4.8%, says a WHO report released Monday. In lower middle-income countries, the number of overweight and obese children younger than 5 has doubled, from 7.5 million to 15.5 million kids.

Almost half of those overweight children (48%) lived in Asia in 2014, and 25% lived in Africa.

The report, prepared by the WHO's Commission on Ending Childhood Obesity, has been two years in the making. The commission called for a "whole-of-government approach" to improve children's diets and promote physical activity. In addition to promoting breastfeeding for infants and promulgating guidelines for healthful eating, governments should implement an "effective tax on sugar-sweetened beverages" to reduce their consumption by children and adolescents, the report says.

"It is well established that the consumption of sugar-sweetened beverages is associated with an increased risk of obesity," the report declares. It notes that low-income families have the greatest risk of obesity and are most responsive to price changes.

"Fiscal policies may encourage this group of consumers to make healthier choices (provided healthier alternatives are made available) as well as providing an indirectly educational and public health signal to the whole population," the report says.

Some countries may also consider levying taxes on "unhealthy foods, such as those high in fats and sugar," the report adds.

In schools, at sports events and in screen-based entertainment, the commission also recommended that governments limit children's exposure to the marketing of unhealthful foods and sugar-sweetened beverages.

"Despite the increasing  number of voluntary efforts by industry, exposure to the marketing of unhealthy foods remains a major issue demanding change that will protect all children equally," the report says.

The report comes at a time when sales of soft drinks across the world have skyrocketed. In countries such as India, Brazil and China, such sales have more than quadrupled over the last decade or so. In 2012, soft drink sales -- 40% of which were controlled by U.S. giants Coca-Cola and PepsiCo -- were estimated at $532 billion.

Meanwhile, sales of packaged and processed foods are also burgeoning in middle-income nations.

The WHO report urges nongovernmental organizations to escalate their efforts to combat child obesity and says the private sector should support the production of and improved access to more healthful foods and beverages. Governments should also coordinate their efforts so that marketing appeals for unhealthful foods and beverages do not cross borders, the commission said.

The report notes that "low physical activity is rapidly becoming the social norm in most countries." It calls on governments to ensure that schools and public spaces make time and space available for children and adolescents to move, and to recommend limits on television viewing. Globally, 84% of girls and 78% of boys ages  11 to 17 fail to get the 60 minutes per day of moderate-to-vigorous physical activity recommended by WHO.

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