A comprehensive new study published in Nature challenges the notion of a single global obesity epidemic, revealing starkly divergent trends across the world. While obesity rates have stabilized in many wealthy nations, including much of Western Europe, they continue to climb—and in some cases accelerate—across low- and middle-income countries.
The research, conducted by the NCD Risk Factor Collaboration—a network of nearly 2,000 scientists—analyzed data from 232 million individuals across 200 countries and territories from 1980 to 2024. The findings underscore that obesity trajectories differ substantially by country, age group, and sex, requiring tailored policy responses rather than one-size-fits-all solutions.
Western Europe: A Plateau and Early Signs of Reversal
In most high-income Western countries, including those in Western Europe, North America, and Australasia, the rise in childhood obesity began to slow during the 1990s and had largely plateaued by the mid-2000s. Denmark was among the earliest to see this stabilization, with rates leveling off around 1990. By the 2010s, countries like France, Italy, and Portugal showed small but meaningful declines in child obesity—the first such national-level reversals observed.
For adults, a similar trend followed roughly a decade later. In 2024, adult obesity prevalence across Western Europe generally remains below 25 percent, with France as low as 11 percent. This contrasts sharply with English-speaking high-income countries: in the United Kingdom, Canada, and the United States, adult obesity rates range from 25 percent to 43 percent.
The Developing World: Rising Rates and Accelerating Pace
The picture is far more alarming in low- and middle-income countries across sub-Saharan Africa, South and Southeast Asia, Latin America, and Pacific Island nations. In many of these regions, obesity rates are not only rising but accelerating. In 2024, the fastest increases—more than half a percentage point per year—were recorded in 36 countries for girls and 35 for boys, with the highest velocities in Tonga and Samoa for girls, and Peru for boys.
Pacific Island nations face extreme prevalence: in Tonga and the Cook Islands, more than 65 percent of adults are now obese. Even in countries where obesity was historically rare, such as Ethiopia, Rwanda, and Bangladesh, rates are now climbing.
Drivers and Policy Implications
The study identifies multiple factors behind these divergent trends, including access to ultra-processed foods, changes in physical activity, income levels, and health system responses. Public policy measures, such as sugar taxes, have shown modest but measurable effects at population scale. However, the authors stress that responses must be tailored to each country's context.
“What is needed is nuanced nutritional and health policies and programmes that are relevant for each country, especially those that support people with lower income and education towards eating healthy foods, having an active lifestyle and using relevant health care interventions to attain and maintain health, functional capacity and quality of life across the life course.”
The study also notes that weight-loss medications could become an important tool, but warns that their variable costs across public and private providers currently limit coverage and may exacerbate inequalities.
For European readers, the findings offer a mixed picture: while Western European countries have largely succeeded in stabilizing obesity rates, the continent's broader engagement with global health—through development aid, trade, and public health partnerships—means these trends have direct implications. As the World Urban Forum in Baku highlighted, cross-border solutions are increasingly needed to address shared challenges like housing and health. Similarly, the obesity divide demands coordinated international action, particularly as European nations continue to influence global food systems and health policies.
