More children worldwide are now obese than underweight, with junk food reportedly to blame.
Ultra-processed foods are driving the change, with 188 million school-age children and teenagers living with obesity – one in 10 globally – according to new UN figures warning of future disease risks.
The data show that 9.4 per cent of five to 19-year-olds are obese, compared with 9.2 per cent who are underweight.
In 2000, nearly 13 per cent were underweight and only 3 per cent obese.
Unicef’s report analysed data from more than 190 countries, using sources including Unicef, the World Health Organization and the World Bank.
It found one in five children aged five to 19 are overweight, with 42 per cent of the 291 million in this group classed as obese in 2022, up from 30 per cent in 2000.
Catherine Russell, executive director of Unicef, said: “When we talk about malnutrition, we are no longer just talking about underweight children.
“Obesity is a growing concern.
“Ultra-processed food is increasingly replacing fruits, vegetables and protein at a time when nutrition plays a critical role in children’s growth, cognitive development and mental health.”
Obesity has overtaken underweight as the more common form of malnutrition in every region of the world except sub-Saharan Africa and South Asia.
It is also a problem in countries where many children still suffer from wasting or stunting caused by lack of food.
The highest rates were recorded in Pacific Island nations, where traditional diets have been replaced by “cheap, energy-dense, imported food”.
In Niue, 38 per cent of five to 19-year-olds are obese, with 37 per cent in the Cook Islands. Prevalence was also high in Chile (27 per cent), the US (21 per cent) and the United Arab Emirates (21 per cent).
In the UK, the proportion of overweight children rose slightly from 29 per cent in 2000 to 30 per cent in 2022, while obesity increased from 9 per cent to 11 per cent.
The steepest increases were seen in low- and middle-income countries, where rates have more than doubled since 2000.
Researchers link this to the spread of “modern retail outlets, online grocery stores and food delivery apps”, with ultra-processed foods often cheaper than fresh or minimally processed alternatives.
Childhood obesity raises the risk of heart disease, type 2 diabetes and some cancers later in life.
Ultra-processed foods – including cereals, biscuits, cakes, fizzy drinks and ready meals – undergo industrial processing and typically contain additives such as colours, emulsifiers and flavours, alongside high levels of sugar, fat or salt.
UPFs “dominate shops and schools”, the report warned, and are heavily promoted to young people and parents digitally, creating an environment where they are difficult to avoid rather than a matter of personal choice.
Nomathemba Chandiwana, chief scientific officer at the Desmond Tutu Health Foundation in Cape Town, said: “We often only think of malnutrition here as underweight or stunting, but obesity has the same long-term consequences.
“About one in eight children are overweight or have obesity, while one in four are stunted. That double burden is shaping a generation’s health.
“Most of the attention and resources go to undernutrition and stunting in the early years, which of course matters, but obesity isn’t always seen as malnutrition, so it slips under the radar.”
She added that children faced “relentless” fast-food marketing, even in schools: “It’s really tough trying to tackle both undernutrition and obesity at the same time.
“South Africa is a middle-income country, but still deeply unequal. Many children grow up both hungry and surrounded by cheap, poor-quality food.”
Unicef has previously estimated that by 2035 the global cost of overweight and obesity will surpass US$4tn (£2.9tn) annually.
The report pointed to Mexico’s ban on ultra-processed food sales in schools as an example of action, but warned that “the unethical business practices of the ultra-processed food and beverage industry undermine efforts to put legal measures and policies in place to protect children from unhealthy food environments”.
It called on governments to introduce clearer labelling, tighter marketing rules, targeted taxes and subsidies.
Recommendations included banning junk food sales and advertising in schools, and expanding support programmes to help low-income families afford healthier diets.
There should be “strong safeguards to protect public-policy processes from interference by the ultra-processed food industry”, the report concluded.
