More than one billion people in the world are now living with obesity, global analysis suggests

The analysis of global data estimates that among the world’s children and adolescents, the rate of obesity in 2022 was four times the rate in 1990. Among adults, the obesity rate more than doubled in women and nearly tripled in men. In total, 159m children and adolescents and 879m adults were living with obesity in 2022.

Between 1990 and 2022, the proportion of the world’s children and adolescents who were affected by underweight fell by around one-fifth in girls and more than one-third in boys. The proportion of the world’s adults who were affected by underweight more than halved over the same period.

Obesity and underweight are both forms of malnutrition and are detrimental to people’s health in many ways. The study provides a highly detailed picture of global trends in both forms of malnutrition over the last 33 years.

Majid Ezzati, a professor at Imperial College London and a senior author, said, “It is very concerning that the epidemic of obesity that was evident among adults in much of the world in 1990 is now mirrored in school-aged children and adolescents. At the same time, hundreds of millions are still affected by undernutrition, particularly in some of the poorest parts of the world. To successfully tackle both forms of malnutrition it is vital we significantly improve the availability and affordability of healthy, nutritious foods.”

The new study was conducted by the NCD Risk Factor Collaboration (NCD-RisC), in collaboration with the World Health Organization (WHO). Researchers analysed weight and height measurements from over 220m people aged five years or older (63m people aged five to 19 years, and 158m aged 20 years or older), representing more than 190 countries. More than 1,500 researchers contributed to the study, which looked at body mass index (BMI) to understand how obesity and underweight have changed worldwide from 1990 to 2022.

Adults were classed as being affected by obesity if they had a BMI greater than or equal to 30kg/m2 and classed as underweight if their BMI was below 18.5kg/m2. Among school-aged children (aged five to nine years) and adolescents (aged 10-19 years), the BMI used to define obesity and underweight depended on age and sex because there is a significant increase in height and weight during childhood and adolescence.

From 1990 to 2022, global obesity rates more than quadrupled in girls (1.7 per cent to 6.9 per cent) and boys (2.1 per cent to 9.3 per cent), with increases seen in almost all countries. The proportion of girls who were underweight fell from 10.3 per cent in 1990 to 8.2 per cent in 2022, and for boys, it fell from 16.7 per cent to 10.8 per cent. Among girls, a decrease in the rates of underweight was detected in 44 countries, whilst among boys, a decrease was noted in 80 countries.

The total number of children and adolescents who were affected by obesity in 2022 was nearly 160 million (65m girls and 94m boys), compared to 31m in 1990. Whereas 77m girls and 108m boys were underweight in 2022, decreasing from 81m for girls and 138m for boys in 1990.

In adults, obesity rates more than doubled among women (8.8 per cent to 18.5 per cent) and nearly tripled in men (4.8 per cent to 14 per cent) between 1990 and 2022. The proportion of adults who were underweight halved between 1990 and 2022 (14.5 per cent to seven per cent in women; 13.7 per cent to 6.2 per cent in men).

In total, an estimated nearly 880m adults were living with obesity in 2022 (504m women and 374m men), four and a half times the 195m recorded in 1990 (128m women and 67m men). Combined with the 159m children living with obesity in 2022, this is a total of over one billion people affected by obesity in 2022. Despite global population growth, 183m women and 164m men were affected by underweight in 2022, 45m and 48m fewer, respectively, than in 1990.

Overall, these trends have led to a transition where in most countries, a larger number of people are affected by obesity than underweight. In 2022, obesity rates were higher than rates of underweight for girls and boys in around two-thirds of the world’s countries (133 countries for girls and 125 countries for boys).

Tedros Adhanom Ghebreyesus, WHO director-general, said, “This new study highlights the importance of preventing and managing obesity from early life to adulthood, through diet, physical activity, and adequate care, as needed.