A bombshell report by the World Health Organization warns of the alarming rate of obesity in young people around the world: It has increased tenfold over the past four decades, with obese children set to exceed the number of underweight children by 2022.

Some 124 million young people aged between 5 and 19 are now obese, the research claims. Another 213 million are overweight but fall short of the obesity threshold. The WHO defines obesity on the basis of body mass index — calculated by dividing a person’s weight in kilograms by the square of height in meters. For example, a 19-year old with a BMI of 25 is said to be overweight, while someone with a BMI of 30 is deemed obese.

Conducted by the WHO in conjunction with Imperial College London and published Wednesday in the Lancet, the study looked at more than 130 million people aged over 5 — the largest number of participants ever involved in an epidemiological study.

While obesity levels in some wealthy European countries have stabilized, in the developing world the crisis is “ballooning.”

China and India have seen huge spikes in childhood obesity in recent years, alongside countries in the Middle East and North Africa.

Polynesia and Micronesia recorded the highest rate of childhood obesity, with a quarter of its young population classed as obese.

However, high-income English-speaking countries, including the U.S., Canada, Australia, New Zealand, Ireland and the U.K., also registered crisis levels of obesity. In a bid to tackle this crisis, some of the countries have introduced a “sugar tax” to increase the piece of high-sugar foods and drinks.

Girls in the U.S. had the 15th highest obesity rate in the world. American boys registered 12th.

The global cost of treating health issues linked to obesity — including type 2 diabetes, heart disease and some forms of cancer — would surpass $1.2 trillion every year from 2025, the World Obesity Federation warned Tuesday.

Imperial’s Professor Majid Ezzati, lead author of the report, blamed the endemic on the availability of cheap, high-calorie food.