Bielefeld – November 04, 2026 -- Germany's federal research ministry is funding a sub-study worth roughly €2 million to test whether regular forest play changes children's risk of allergies, asthma and ADHD. The trial sits inside a long-term cohort of about 1,000 newborns in the East Westphalia-Lippe region.
The parent project, "Kleine Eulen OWL", is run by a research team at Evangelisches Klinikum Bethel (EvKB) at University Hospital OWL. The source describes it as unique nationwide. It follows the children into adulthood to map how the microbiome develops and how early living conditions affect later disease risk. Over the first six years of life, researchers analyze the influence of genes, pregnancy and birth, stress, environment, family, pets, lifestyle and medication on the microbiome.
Study lead Prof. Eckard Hamelmann, director of EvKB's university clinic for pediatrics, says many microorganisms are not pathogenic and help support immune defense. Research lead Dr. Patricia Maasjosthusmann says the team assumes that early contact with natural microorganisms shapes immune development. The ENDEMIC study tests whether, and to what extent, that contact alters disease risk. Rising rates of chronic illness make the findings relevant, according to the source.
ENDEMIC assigns 23 families to weekly forest sessions
In the second phase, 23 randomly assigned families spend one hour per week in the forest from April to October. About 20 further families form the control group. The Bielefeld association Natursinn supervises the forest play group.
First phase mapped biodiversity around 200 family homes
In the first phase, researchers surveyed 200 participating families on where and how their children play, including whether they dig in sandboxes or soil. The team also recorded plants and trees in gardens and adjacent green spaces, took soil samples and evaluated map data.
Microbiome swabs will yield first results in 2027
The team tracks microbiome development through regular swabs and samples. First results are expected in 2027. Researchers hope to derive simple, practical advice for parents. They also see possible input for urban and landscape planning, such as playgrounds with more contact to microorganism-rich soil, and for new therapies that support the microbiome.