A new study suggests that the global rise in obesity is not inevitable, with rates in some high-income countries levelling off or potentially declining. Researchers from Imperial College London and an international team of nearly 2,000 scientists analysed data from 4,050 population-based studies involving 232 million participants aged five and above, covering the period from 1980 to 2024.
The study, published in the journal Nature, found that while obesity prevalence increased in almost all countries over the 45-year period, many high-income nations experienced a slowdown. In the US and UK, the rate of growth has slowed, with obesity prevalence reaching 40-43% and 27-30% respectively in 2024. In France, rates may have started to decline, with 11-12% of adults affected, while Germany has plateaued at 20-23% and Finland continues to see steady increases.
Slowdowns were often observed in children and adolescents before adults. In Denmark, the slowdown began as early as 1990, and by the mid-2000s, rates stabilised in most high-income countries. Obesity has plateaued in boys and girls in the UK, US, Germany and Japan at prevalences of 10-12%, 20-23%, 7-12% and 3-7% respectively.
In contrast, obesity among young people and adults in many low- and middle-income countries continues to rise, and in some cases is accelerating. The researchers emphasise the need to understand the factors behind these trends, which may include country-specific social, economic and policy considerations, such as body image perceptions and interventions like healthy school meals.
Professor Naveed Sattar of the University of Glasgow, who was not involved in the study, noted that English-speaking nations are doing particularly poorly, with the UK now among the countries with the highest obesity levels worldwide. He called for understanding what has worked in countries where rates have plateaued, and highlighted the potential impact of weight-loss medicines and public health measures on future trends.
