The World Health Organization has noted an "alarming" trend in childhood obesity, estimating in a just-released report that 41 million children under the age of five are overweight.
"Children with obesity are very likely to remain obese as adults and are at risk of chronic illness," the UN health agency said on Monday, warning that the current trend "has the potential to negate many of the health benefits that have contributed to increased life expectancy".
The rate of overweight or obese children in this age group reached 6.1 per cent in 2014, according to the latest available data provided by WHO in Geneva.
The number of unhealthily heavy children stood at 31 million in 1990, amounting to 4.8 per cent.
The biggest increases in that time span were recorded in countries with low and medium incomes, where numbers have more than doubled from 7.5 million to 15.5 million.
WHO reported that countries that have been facing hunger now also have a child obesity problem, since undernourished infants have a much higher risk of becoming overweight later once they eat more and adopt a more sedentary lifestyle.
"Childhood obesity is often under-recognised as a public health issue in these settings, where, culturally, an overweight child is often considered to be healthy," WHO experts said in their report.
In general, childhood obesity is caused by food and drinks that contain too much sugar, salt and fats, as well as by a lack of physical activity.
In addition, babies born to obese or diabetic mothers have a higher risk of becoming overweight themselves.
Obesity in children can cause various illnesses, including heart diseases and diabetes, and it can contribute to depression and low school performance, according to the UN report.
WHO made several recommendations to fight obesity, such as calling for government policies that promote healthy diets and the taxation of unhealthy foods.
Countries should also develop programs to get children moving, WHO said.
