Number of people living with obesity has surpassed one billion

Obesity rates have skyrocketed over the last decade, increasing four-fold in children and adolescents, and doubling in adults, according to new research.

The study, published in The Lancet, also found that rates of underweight are falling globally, meaning obesity is now the most common form of malnutrition in many countries.

There are now more than one billion people living with obesity globally, and the researchers are warning of the major public health challenges that could arise if this trend continues.

Professor Simon Kenny, NHS England’s National Clinical Director for Children and Young People, described the research as “alarming” and warns that obesity can have a detrimental impact on young people, increasing their risk of many avoidable diseases.

Prof Kenny says while the NHS is committed to supporting families affected by weight issues, it “cannot solve this issue alone”, and continued

Study used obesity data from more than 190 countries

The new study was conducted by the NCD Risk Factor Collaboration (NCD-RisC), in collaboration with the World Health Organization (WHO). More than 1,500 researchers contributed to the study which looked at Body Mass Index (BMI) changes between 1990 and 2022.

Researchers analysed the weight and height measurements of over 220 million people aged five years or older across more than 190 countries.

Adults were classed as obese if they had a BMI greater than or equal to 30kg/m² and classed as underweight if their BMI was below 18.5kg/m². The BMI used to define obesity in school aged children and adolescents varied depending on age and sex.

From 1990 to 2022, global obesity rates more than quadrupled in young people, with increases seen in almost all countries. Among girls, a decrease in the rates of underweight was detected in 44 countries, whilst among boys, a decrease was noted in 80 countries.

Obesity rates more than doubled among adults between 1990 and 2022, while the proportion of adults who were underweight halved during the same period.

In total, the researchers estimate that a total of 880 million adults and 159 million children were living with obesity in 2022, taking the total to more than one billion. Meanwhile, the number of adults who are underweight has dropped by 93 million to 347 million.

Hundreds of millions affected by undernutrition

Senior author Professor Majid Ezzati, of Imperial College London, said while it is “very concerning” to see the rise in obesity worldwide, we must pay attention to the hundreds of millions who are still affected by undernutrition, particularly in 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,” he said.

The rise in the double burden of both obesity and underweight has been greatest in some low-income and middle-income countries, particularly those in Polynesia and Micronesia, the Caribbean, and the Middle East and North Africa. These countries now have higher obesity rates than many high-income industrialised countries, especially those in Europe.

Dr Guha Pradeepa, study co-author from the Madras Diabetes Research Foundation, is now warning that major global issues risk worsening both forms of malnutrition.

She said: “The impact of issues such as climate change, disruptions caused by the Covid-19 pandemic, and the war in Ukraine risk worsening both rates of obesity and underweight, by increasing poverty and the cost of nutrient-rich foods.

“The knock-on effects of this are insufficient food in some countries and households and shifts to less healthy foods in others. To create a healthier world, we need comprehensive policies to address these challenges.”

The importance of preventing and managing obesity

The authors acknowledge that BMI is an ‘imperfect measurement’ of the extent and distribution of body fat, but highlight that is one of the only weight measurements which is widely recorded.

Furthermore, some countries had little data and three had no studies, meaning their estimates are more uncertain. Data availability also varied depending on the age group concerned, with less data available for young children and older adults, which makes it more difficult to provide accurate estimates for these age groups.

Nevertheless, Dr Tedros Adhanom Ghebreyesus, WHO Director-General, says the study highlights the importance of preventing and managing obesity from early life to adulthood.

“Getting back on track to meet the global targets for curbing obesity will take 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 impacts of their products,” he said.