Researchers across Europe are pooling data and expertise while working with schools, hospitals and families to find better ways to tackle childhood obesity.
Dr Eleftheria Vellidou believes childhood obesity in Europe has reached epidemic proportions, and the figures back her up. Around one in four children aged 7 to 9 in Europe are living with overweight, including obesity, according to the latest World Health Organization Europe survey, which examined about 470 000 children in 37 countries.
Rates climbed sharply for decades and have only recently levelled off, but experts still consider the figures alarming. Beyond the physical toll, obesity in childhood can bring bullying and stigma. It raises the long-term risk of diabetes, cardiovascular disease, cancer and other serious illnesses, too.
Vellidou, a biomedical engineering researcher at the National Technical University of Athens, is a member of the team coordinating BIO-STREAMS, a four-year EU-funded research initiative involving experts from across Europe.
Seeing the bigger picture
Obesity has complex biological, environmental, behavioural and genetic roots, yet many public discussions focus on food choices and physical activity alone.
The team is therefore drawing on colleagues from different disciplines, working with schools and healthcare professionals to understand why rates of childhood and adolescent obesity remain so high.
Part of the difficulty is that research on childhood obesity tends to be fragmented. Information gathered in one country or study can be hard to compare with data collected elsewhere.
“When we came together to study obesity as an epidemic, we realised we were missing a strong and robust framework that would allow researchers from different disciplines to collaborate,” said Vellidou.
The answer was to build a shared resource large and consistent enough to reveal patterns no single country’s data could show. The team is working across 15 European countries to create the EU’s first dedicated childhood and adolescent obesity biobank, pulling together biological samples, health records, and behavioural and lifestyle data.
A biobank is a shared, organised store of samples and data that researchers can keep drawing on, rather than starting from scratch each time. Every partner gathers information to the same standard, so a result from a clinic in Athens, Greece, can be compared directly with one from Maribor, Slovenia.
This bigger pool of data, the researchers hope, will help them move beyond describing obesity and towards understanding what drives it and why it affects children so differently.
Looking beyond simple explanations
Vellidou says this broader approach could help explain why some children are more vulnerable than others, and why some go on to develop serious health problems while others remain metabolically healthy.
“Our target is to shed light on the causality of obesity,” she said. “To do that, you need data that researchers can access in large quantities. We have the tools in place for researchers on related projects to participate and help expand the sample size.”
Beyond collecting data, the researchers are developing tools to identify children at risk of adverse metabolic outcomes and support more personalised prevention and healthy living.
The digital platform will combine risk assessment with tailored recommendations for children and their families, shifting the focus away from the assumption that the answer is simply to eat less and exercise more.
Schools at the heart of change
Understanding the problem also means looking at where children spend their time, so the researchers are working with schools and hospitals in several countries to explore how prevention and support can work in everyday life.
School pilots in Greece, Portugal, Slovenia, Denmark and the Netherlands are looking at ways to promote healthier habits while tackling the psychological difficulties associated with childhood obesity, including bullying and stigma.
Alongside these, seven hospitals in six countries are running clinical pilots, working directly with children and families as new approaches are developed and tested.
Having both settings matters. Schools reach children early and in large numbers, while hospitals allow closer clinical tracking of those already identified as at risk. The clinical studies are now recruiting participants, while researchers analyse existing data and gather new information from the pilots in parallel.
“When someone is obese, the first thing people think is that they should eat less and that it’s their fault,” said Petra Van Haren, director of the European School Heads Association (ESHA) based in the Netherlands.
“There is blaming and shaming amongst kids, too. But every child has a right to be proud of themselves. Schools want children who are confident and like themselves the way they are. At the same time, they also want to support obesity prevention.”
ESHA has members in 30 European countries, putting its headteachers in a strong position to influence school policies and, consequently, children’s lives, on a large scale. Workshops in the five pilot countries let children take part in activities designed to promote movement, improve nutrition knowledge and encourage positive lifestyle choices.
“We want to make a difference. Despite the large number of programmes that have run in schools, we haven’t been able to make enough of a change,” said Van Haren. “We are hopeful this project could tip it in the right direction.”
School activities include workshops, games and challenges developed jointly by researchers and education specialists. School leaders want these approaches to become long-term policy that shapes the whole school day.
“Whatever we teach them in these fundamental years will really influence the rest of their lives,” added Van Haren.
Bringing families on board
Schools cannot do this alone, so families are also encouraged to take part through the Active Health app that uses games and interactive activities to teach children and parents about healthy habits.
A preliminary version was tested in Barcelona in May 2025 and is now being refined. The activities are kept simple, to encourage family participation without adding pressure on busy parents. One, for example, asks children and parents to plan a meal together.
“The fact of sitting down with your parents is already very positive,” said Van Haren. “It’s just a few minutes to talk about what you want to eat.”
Small, everyday moments like this sit at the heart of the project’s approach to families. Rather than asking them to make sweeping changes, the aim is to build healthier choices into life as it already runs. The school teams also help families find local resources, such as sports facilities and playgrounds.
Stronger together
BIO-STREAMS is part of OBEClust, a network of nine European obesity projects involving hundreds of researchers and tens of millions of euros in EU investment. For the researchers, that collaboration is essential to real progress against childhood obesity.
The team is already looking past the project’s end in April 2027. The biobank and digital platform are designed to continue as shared resources for researchers, while a Community Network will connect families, schools, clinicians and policymakers, and help people find support locally.
It will also promote evidence-based information and reduce stigma through weight-neutral approaches that focus on health, not weight alone.
For the millions of children behind that one-in-four figure, the hope is that this research will help Europe move towards a better understanding of childhood obesity, and, ultimately, better ways of preventing and managing it.
This article was originally published in Horizon the EU Research and Innovation Magazine.
Research in this article was funded by the EU’s Horizon Programme.
