UNICEF report: For first time, more children are obese than underweight worldwide

More children worldwide are living with obesity than underweight for the first time, according to a new UNICEF Child Nutrition Report that projects 9.4% of school-age children (ages 5–19) are obese compared with 9.2% who are underweight. The agency says the reversal reflects converging trends over the past 25 years and signals a major change in the global burden of malnutrition.

UNICEF bases the 2025 crossover on survey data and projections through 2022, and it warns that while the precise year has some uncertainty the overall trend is clear and continuing upward. The report estimates about 188 million children now live with obesity and projects child obesity rates will continue to rise through 2030, particularly in Latin America, the Middle East and East Asia. Public health experts say the early onset of obesity raises long-term risks for Type 2 diabetes, hypertension, cardiovascular disease and certain cancers and will carry rising economic costs; one projection cited in the report estimates overweight and obesity could drain more than $4 trillion a year globally by 2035, roughly 3% of world GDP.

The shift reflects a broader redefinition of malnutrition that includes both insufficient food and excesses of poor-quality calories as well as hidden micronutrient deficiencies. Twenty-five years ago, nearly 13% of children were underweight while just 3% had obesity; the new figures show those lines have converged and flipped. UNICEF and public health researchers say the decline in underweight children is a significant achievement because severe undernutrition is linked to stunting, impaired cognitive development, weakened immunity and higher mortality.

Experts point to changes in the global food environment and activity patterns as central drivers of rising obesity. Supermarkets, schools and corner stores increasingly stock calorie-dense, highly processed products high in added sugars, saturated fat and salt — items that are often inexpensive, convenient and heavily marketed. A randomized trial at the U.S. National Institutes of Health cited in the report found participants on ultra-processed diets consumed about 500 extra calories per day compared with those on minimally processed diets. Rafael Pérez-Escamilla, a professor of public health nutrition at Yale University, said that body of evidence "is as close as you can get to a causal relationship [in public health]."

The label "ultra-processed" is debated among researchers. Critics like Nicola Guess say definitions can be too broad and lump dissimilar items together, making the category less precise. Still, many studies show consistent associations between diets high in highly processed products and poorer health outcomes.

Lower physical activity compounds the effect of poorer diets. Global surveys cited by UNICEF show more than 80% of adolescents do not meet the World Health Organization recommendation of at least one hour of moderate-to-vigorous activity daily, increasing the risk that excess caloric intake will translate into weight gain and related diseases.

The rise in obesity is uneven geographically. Higher-income countries and some middle-income nations report the highest prevalence: the United States and the United Arab Emirates are among those with double-digit or near–double-digit obesity rates in school-age children, and Chile reported a 27% childhood obesity rate in recent surveys. In parts of the Pacific Islands, more than a third of children are obese. By contrast, underweight remains more common in much of sub-Saharan Africa and South Asia, producing a patchwork in which some regions face persistent undernutrition while others confront steep rises in overweight and obesity.

Governments have responded with a range of policies that aim to change the food environment. Chile's 2016 warning-label law combined front-of-package warnings with restrictions on advertising and school sales; research indicates the measures reduced purchases of sugary drinks and energy-dense snacks. Mexico recently banned the sale of junk food in public schools for roughly 34 million children, and the United Kingdom's soft drinks tax has encouraged beverage reformulation to reduce sugar content. In the United States, critics and some nutrition researchers say federal action has been slower and less stringent: proposed front-of-package labeling by the Food and Drug Administration falls short of the stop-sign warnings used in parts of Latin America, and some policy groups have urged more aggressive marketing restrictions, taxes and labeling requirements.

Policy experts say no single law will reverse the trend and that effective strategies will need to address pricing, marketing, availability and the broader commercial drivers of food choice. "Food companies are not social service or public health agencies; they are businesses with stockholders to please," Marion Nestle, a nutrition scholar at New York University, wrote in an email, arguing that commercial incentives shape product portfolios and marketing practices.

UNICEF's report frames the crossover as both progress and a new challenge. The reduction in underweight children is a public health gain, but the rapid increase in obesity reframes malnutrition in the 21st century as a problem driven not only by scarcity but also by the quantity and quality of calories available to children. The agency and outside researchers stress that reversing the obesity trend will require structural policy changes and sustained action across countries, tailored to differing regional realities and the coexistence of undernutrition and overnutrition in many places.

As the global tally of childhood obesity grows, health systems and policymakers face decisions about which interventions can curb further increases while preserving gains in reducing underweight and micronutrient deficiencies. UNICEF's projections through 2030 signal that the balance of malnutrition challenges will continue to shift unless systems shaping children's diets and activity levels are altered.