Obesity exceeds underweight for the first time among school-age children and adolescents globally – UNICEF

BANGKOK/NEW YORK, 10 September 2025 – Obesity surpassed underweight as the more prevalent form of malnutrition this year, affecting 1 in 10 – or 188 million – school-aged children and adolescents. This places them at risk of life-threatening diseases, UNICEF warned in a report released today.

Feeding Profit: How Food Environments are Failing Children draws on data from over 190 countries and finds the prevalence of underweight among children aged 5-19 has declined since 2000, from nearly 13 per cent to 9.2 per cent, while obesity rates have increased from 3 per cent to 9.4 per cent. Obesity now exceeds underweight in all regions of the world, except sub-Saharan Africa and South Asia.

According to the findings, several Pacific Island countries have the highest prevalence of obesity globally, including 38 per cent of 5 to 19-year-olds in Niue, 37 per cent in Cook Islands, and 33 per cent in Nauru. These levels – which have all doubled since 2000 – are largely driven by a shift from traditional diets to cheap, energy-dense, imported foods.

Many high-income countries continue to have high levels of obesity. For example, 27 per cent of 5 to 19-year-olds in Chile are living with obesity, as are 21 per cent in the United States, and 21 per cent in the United Arab Emirates.

"When we talk about malnutrition, we are no longer just talking about underweight children," said UNICEF Executive Director Catherine Russell. "Obesity is a growing concern that can impact the health and development of children. 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."

In Thailand, childhood overweight and obesity have more than doubled over the past 25 years, ranking the country among the top four most affected in ASEAN. Rates have increased from 6 per cent to 13 per cent among children aged 6–14. Approximately 14 per cent of Thai adolescents (ages 15–18) are now overweight or obese, and projections from the World Obesity Federation show that by 2035, more than 60 per cent of Thai children aged 5–19 could be overweight or obese.

While undernutrition – such as wasting and stunting – remains a significant concern among children under 5 in most low- and middle-income countries, the prevalence of overweight and obesity is increasing among school aged children and adolescents. According to the latest available data, 1 in 5 children and adolescents aged 5-19 globally – or 391 million – are overweight, with a large proportion of them now classified as living with obesity.

Children are considered overweight when they are significantly heavier than is healthy for their age, sex and height. Obesity is a severe form of overweight and leads to a higher risk of developing insulin resistance and high blood pressure, as well as life-threatening diseases later in life, including type-2 diabetes, cardiovascular disease, and certain cancers.

The report warns that ultra-processed and fast foods – high in sugar, refined starch, salt, unhealthy fats and additives – are shaping children's diets through unhealthy food environments, rather than personal choice. These products dominate shops and schools, while digital marketing gives the food and beverage industry powerful access to young audiences.

In Thailand, this trend is linked to rapid changes in the food retail sector where convenience stores and hypermarkets have expanded significantly over the past 15 years, alongside a 70 per cent increase in per capita sales of processed foods. Online food delivery has surged, with sales from fast-food restaurants via delivery apps increasing by more than 650 per cent between 2013 and 2021.

In a global poll of 64,000 young people aged 13-24 from over 170 countries - conducted through UNICEF's U-Report platform last year - 75 per cent of respondents recalled seeing advertisements for sugary drinks, snacks, or fast foods in the previous week, and 60 per cent said the advertisements increased their desire to eat the foods. Even in conflict-affected countries, 68 per cent of young people said they were exposed to these advertisements.

Without interventions to prevent childhood overweight and obesity, countries could face lifetime health and economic impacts as a result of the health issues caused.. The cost to Peru, for example, could exceed US$210 billion. By 2035, the global economic impact of overweight and obesity is expected to surpass US$4 trillion annually. In Thailand, the economic loss from obesity is already estimated at US$8 billion and could reach US$21 billion by 2030 if no action is taken.

The report highlights positive steps governments have taken. For example, in Mexico – a country facing a high prevalence of childhood and adolescent obesity, where sugary drinks and ultra-processed foods account for 40 per cent of children's daily calories -the Government recently banned the sale and distribution of ultra-processed foods and items high in salt, sugar and fat in public schools. This has positively impacted the food environments of over 34 million children.

In Thailand, evidence clearly shows that marketing and advertising strongly influences children's eating behaviours. UNICEF Thailand is supporting the Ministry of Public Health to strengthen regulations on the marketing of unhealthy foods and drinks to children, in line with the World Health Organization recommendations. Thailand has already introduced an excise tax on sugar-sweetened beverages, which has reduced sugar content in taxed drinks by 10 per cent, but further legislation is needed to address rising obesity rates.

UNICEF Thailand recently launched "Kin Rai Dee" (What's Good to Eat), a nationwide campaign to inspire young people and parents to make healthier food choices. The campaign - targeting Gen Z (aged 13-24) and parents of young children - aims to raise awareness of the risks of poor nutrition while providing practical solutions to develop better eating habits.

To transform food environments and ensure children have access to nutritious diets, UNICEF is calling on governments, civil society, and partners to urgently:

• Implement comprehensive mandatory policies to improve children's food environments, including food labelling, food marketing restrictions, and food taxes and subsidies.
• Implement social and behaviour change initiatives that empower families and communities to demand healthier food environments.
• Ban the provision or sale of ultra-processed and junk foods in schools and prohibit food marketing and sponsorship in schools.
• Establish strong safeguards to protect public policy processes from interference by the ultra-processed food industry.
• Strengthen social protection programmes to address income poverty and improve financial access to nutritious diets for vulnerable families.

"In many countries we are seeing the double burden of malnutrition – the existence of stunting and obesity. This requires targeted interventions," said Russell. "Nutritious and affordable food must be available to every child to support their growth and development. We urgently need policies that support parents and caretakers to access nutritious and healthy foods for their children."

Notes for editors:

The Child Nutrition Report 2025 draws on data from over 190 countries and includes household surveys, modelled estimates, projections, and polls.

Data on overweight, stunting and wasting among children under the age of 5 from 2000-2024 are based on UNICEF/WHO/World Bank Joint Child Malnutrition estimates.

For children and adolescents aged 5-19 years, data on overweight, obesity and underweight is modelled using population-based surveys, administrative data or studies that measured height and weight in representative samples. Country level data is available from 2000-2022 and coordinated by the Non-Communicable Disease Risk Factor Collaboration (NCD-RisC).

To ascertain obesity surpassing underweight among children aged 5-19 years, UNICEF projected prevalence from 2022 onwards, based on trends in prevalence of obesity and underweight from 2010 to 2022.

Categories of overweight, obesity and underweight (thinness) are defined based on body mass index (BMI). For school-aged children and adolescents aged 5-19 years:  

• Overweight is defined as a BMI greater than 1 standard deviation above the median, according to the WHO references for school-age children and adolescents.
• Obesity is defined as a BMI greater than 2 standard deviations above the median, according to the WHO references for school-age children and adolescents.
• Underweight, also known as thinness, is defined as a BMI less than 2 standard deviations below the median, according to the WHO references for school-age children and adolescents.

Child malnutrition has three dimensions: undernutrition (stunting and wasting), overweight/obesity and hidden hunger or micronutrient deficiencies.

Ultra-processed foods are industrially formulated foods and beverages made primarily from refined ingredients and additives, with little or no whole foods. They often contain high levels of added sugars, refined starches, salt, and unhealthy fats, and are designed to be convenient, highly palatable, and appealing through marketing, packaging, and branding. 

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