WHO study: obesity plateau in wealthy nations

The NCD Risk Factor Collaboration said in a Nature paper published on May 13 that the global obesity story is no longer moving in one direction. Its analysis found that obesity growth has slowed, plateaued or in some cases begun to reverse in many high-income countries, while rates continue to rise across many low- and middle-income countries. (nature.com) The study drew on measured height and weight data from 232 million people in 4,050 population-based studies covering 200 countries and territories from 1980 to 2024. (pmc.ncbi.nlm.nih.gov) Researchers said that scale makes it the largest analysis of its kind and allows them to compare not just obesity prevalence, but the pace at which it has been changing over time. (nature.com) ### What exactly did the researchers find? The Nature paper said the rise in obesity among school-aged children and adolescents began to decelerate through the 1990s in many high-income countries and later plateaued in most of them. (nature.com) In adults, the slowdown came about a decade later, followed in some places by a plateau or a small reversal. Imperial College London, which said the work was led through the collaboration known as NCD-RisC, named France, Italy and Portugal among countries where child obesity rates may have begun to decline. The paper also cited Spain as an example where adult obesity may have shown a small reversal. (pmc.ncbi.nlm.nih.gov) ### Which countries still stand out on the high end? Euronews reported that adult obesity prevalence in 2024 remained below 25% across much of Western Europe and was as low as 11% in France. The same report said adult obesity rates ranged from 25% to 43% in the United Kingdom, Canada and the United States. (pmc.ncbi.nlm.nih.gov) The Nature abstract said the plateau in high-income countries still occurred at very different levels. Among children and adolescents, age-standardized prevalence ranged from 3% to 4% for girls in Japan, Denmark and France to 23% for boys in the United States. (imperial.ac.uk) ### Where are rates still climbing fastest? The paper said most low- and middle-income countries showed stable or increasing annual changes in obesity prevalence even after some had surpassed high-income countries in overall prevalence. Imperial and LSHTM both said the continuing increases were concentrated across parts of Africa, Asia, Latin America, and Pacific and Caribbean island nations. (euronews.com) Kalpana Sabapathy of the London School of Hygiene & Tropical Medicine said the contrast between progress in high-income countries and rising obesity in lower-income settings showed a widening divide, especially for children and young people. (pmc.ncbi.nlm.nih.gov) Majid Ezzati of Imperial College London said the findings challenge describing obesity as a single global epidemic because country trajectories differ. ### Why are researchers talking about the “velocity” of obesity? STAT reported that the study focused on the “velocity” of obesity, meaning how quickly prevalence is rising or falling, rather than only comparing absolute levels across decades. (pmc.ncbi.nlm.nih.gov) That approach helps explain why two countries can both have high obesity rates but be moving in different directions. The authors said this matters because obesity policy is not starting from the same place everywhere. Their paper said differences in the availability, affordability and use of foods may have helped slow obesity growth in wealthier countries, while lower-income countries need policy interventions during economic and nutritional transitions. (lshtm.ac.uk) ### What happens next? Nature published the paper on May 13, and the findings were linked by Imperial and LSHTM to the European Congress on Obesity 2026 in Istanbul. The congress website lists the meeting dates as May 12 through May 15. (statnews.com) The underlying dataset is also publicly described in open-access records tied to the paper, which identify the study period as 1980 to 2024 and the collaboration as NCD-RisC. That gives researchers and policymakers a country-by-country baseline for future updates. (pmc.ncbi.nlm.nih.gov) (imperial.ac.uk)