One billion people worldwide suffer from obesity. How many times has the rate of this disease increased in the last 30 years

Obesity rates have risen dramatically over the past three decades, according to new analysis by the School of Public Health at Imperial College London.

Obesity rates have tripled in the last 30 years in men PHOTO Shutterstock

According to the study published in The Lancet, one in eight people are obese, and this highlights changes in global trends in malnutrition over a period of more than 30 years.

The paper finds that the total number of children, adolescents and adults worldwide who are obese has exceeded one billion.

The report points out that these trends, together with the decline in the prevalence of underweight people since 1990, make obesity the most common form of malnutrition in most countries.

Researchers estimate that among the world's children and adolescents, the obesity rate in 2022 was four times higher than in 1990. While among adults, the obesity rate has doubled in women and nearly tripled in men.

In total, approximately 159 million children and adolescents and 879 million adults were obese in 2022.

According to the researchers, the recent findings underscore the urgent need for comprehensive policies to address the burden of malnutrition, such as improving access to nutritious food, as well as strategies to prevent and manage obesity and undernutrition.

Professor Majid Ezzati, from Imperial College London's School of Public Health and lead author of the study, said: “It is of great concern that the obesity epidemic that was evident among adults in much of the world in 1990 is now reflected among school-aged children and adolescents.

At the same time, hundreds of millions are still affected by malnutrition, especially in some of the poorest parts of the world. To successfully address both forms of malnutrition, it is vital that we significantly improve the availability and accessibility of healthy and nutritious food.

Alarming rise in obesity rates in children and adolescents

In the latest study, carried out by the Risk Factors for Noncommunicable Diseases (NCD-RisC) collaboration in collaboration with the World Health Organization (WHO), researchers looked at trends in obesity and undernutrition – both forms of malnutrition that are harmful to health.

The researchers analyzed weight and height measurements from more than 220 million people aged five years or older (63 million people aged five to 19 years and 158 million people aged 20 years or older more), from over 190 countries.

More than 1,500 researchers contributed to the study, which examined body mass index (BMI) to understand how obesity and undernutrition have evolved worldwide between 1990 and 2022.

Diet and lack of physical exercise, among the factors of childhood obesity

Diet and lack of physical exercise, among the factors of childhood obesity PHOTO Shutterstock

They found that between 1990 and 2022, the proportion of the world's children and adolescents who were undernourished fell by about a fifth for girls and by more than a third for boys. The percentage of the world's adults who were undernourished fell by more than half during the same period.

Adults were classified as obese if they had a BMI greater than or equal to 30 kg/m2 and classified as underweight if their BMI was below 18.5 kg/m2.

Among school-aged children (aged five to nine) and adolescents (aged 10 to 19), the BMI used to define obesity and underweight depended on age and sex, as there was an increase significant change in height and weight during childhood and adolescence.

Between 1990 and 2022, global obesity rates quadrupled in girls (1.7% to 6.9%) and boys (2.1% to 9.3%), with increases seen in almost all countries . The percentage of girls who are underweight has fallen from 10.3% in 1990 to 8.2% in 2022, and that of boys has fallen from 16.7% to 10.8%. Among girls, a decrease in underweight rates was detected in 44 countries, while among boys, a decrease was observed in 80 countries.

160 million children and adolescents affected by obesity

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

In adults, obesity rates doubled in women (8.8% to 18.5%) and tripled in men (4.8% to 14.0%) between 1990 and 2022. Percentage of adults who were underweight halved between 1990 and 2022 (14.5% to 7.0% in women; 13.7% to 6.2% in men).

In total, approximately 880 million adults were obese in 2022 (504 million women and 374 million men), four and a half times more than the 195 million recorded in 1990 (128 million women and 67 million men) .

Together with the 159 million children who were obese in 2022, this is a total of more than one billion people affected by obesity in 2022. Despite the increase in the global population, 183 million women and 164 million men were underweight in 2022, 45 million and 48 million fewer than in 1990, respectively.

Overall, these trends have led to a transition where, in most countries, more people are affected by obesity than underweight. In 2022, obesity rates were higher than underweight rates for girls and boys in about two-thirds of the world's countries.

Dr. Tedros Adhanom Ghebreyesus, Director-General of WHO, said: “This new study highlights the importance of preventing and managing obesity from childhood to adulthood through diet, physical activity and appropriate care as needed.”

Returning to global obesity reduction targets will require the work of governments and communities, supported by evidence-based policies from WHO and national public health agencies. Importantly, it requires the cooperation of the private sector, which must be accountable for the health impact of their products.