Some health benefits of living in cities may be diminishing for children across much of the world, especially in wealthy countries such as the US, UK, and France, according to a new study.
The research, published in the journal Nature, analysed trends in child and adolescent height and body mass index (BMI), including data from over 71 million children across urban and rural areas of 200 countries from 1990 to 2020.
Research on child development in the 20th century previously found that cities provide a range of opportunities for better education, nutrition, sports, and healthcare, contributing to school-aged kids and adolescents being taller in cities than those in rural areas in most wealthy nations.
However, in the latest study, scientists led by those from Imperial College London have found that this urban advantage has shrunk in most countries in the 21st century due to accelerating improvements in height for children and adolescents in rural areas.
Researchers also found that children living in cities on average had a slightly higher BMI than kids in rural areas in 1990.
But by 2020, scientists say BMI averages rose for most countries, and particularly faster for urban children.
“Cities continue to provide considerable health benefits for children and adolescents. Fortunately, in most regions, rural areas are catching up to cities thanks to modern sanitation and improvements in nutrition and healthcare,” Anu Mishra, lead author of the study from Imperial College London, said in a statement.
The study also found that the level of change between urban and rural areas varied greatly among different middle and low-income countries, while across high-income countries small urban-rural differences remained stable.
In some middle-income countries, including Chile and Brazil, researchers report the biggest gains in rural children’s height over the three decades.
“These countries have made great strides in levelling up. Using the resources of economic growth to fund nutrition and health programmes, both through schools and in the community, was key to closing the gaps between different areas and social groups,” Majid Ezzati, another author for the study, said.
“The issue is not so much whether children live in cities or urban areas, but where the poor live, and whether governments are tackling growing inequalities with initiatives like supplementary incomes and free school meal programmes,” Dr Ezzati said.
Contrary to the assumption that urbanisation is the main driver of the obesity epidemic, researchers also found that many high-income western countries have had very little difference in height and BMI over time.
“Our findings should motivate policies that counter poverty and make nutritious foods affordable to make sure that children and adolescents grow and develop into adults who have healthy and productive lives,” Dr Ezzati said.
“Programmes like healthy food vouchers for low-income families and free school meal programmes can also provide lifelong benefits for children and adolescents’ health and wellbeing,” he added.