Playing with mud and soil in creche changed children’s immune systems

Playing among forests and parklands — rather in than concrete and gravel yards — helps children to foster a stronger immune system, a study has concluded.

Our gradual shift to more urban living and a world where everything is made clean, safe and 'man-made' for our children, is actually bad news for their immune system – and now some Finnish researchers have the study to prove it. Previous research has looked at how people living in cities and urban areas may be at a greater risk of immune-mediated diseases thanks to a lack of exposure to diverse microbiota, meaning more conditions like asthma, eczema, inflammatory bowel disease, multiple sclerosis and type 1 diabetes – which we are indeed witnessing today. And now this latest Scandinavian study has provided another piece to the puzzle, showing how playing among forests and parklands — rather in than concrete and gravel yards — helps children to foster a stronger immune system.

To conduct their study, researchers from Finland renovated the outdoor play areas of four nurseries with plants, grasses and soil — finding that it had a positive impact in just one month.

Environmental researcher Aki Sinkkonen of the University of Helsinki and his colleagues set about altering the outdoor play spaces of four nurseries in Finland, where they overhauled the previously 'bare' concrete-, sand- and gravel-covered yards with the introduction of wood-like elements including grass, mosses, small shrubs, planting boxes, and natural forest floor.

Over the course of 28 days, the children attending the nurseries — each aged between 3–5 — spent 1.5 hours each day in the green renovated spaces playing games, planting vegetation and crafting with natural materials.

What they found? The children who played in the greener spaces maintained more diverse skin and gut microbiota, the team said — along with signs of a better-regulated immune system.

Skin swabs for microorganisms were taken from each of the 75 children involved in the study both before and after the research period — along with blood and stool samples — and the researchers also analysed soil or sand samples from the yards before and after.

The team compared these nurseries with three 'standard' childcare centres whose yards were left bare, as well as three 'nature-orientated' establishments where children were taken to nearby forests on a daily basis.

Sinkkonen and his team found that the children attending the four renovated nurseries maintained a high diversity in their skin microbiota across the length of the study.

The kids also developed a higher ratio of anti-inflammatory cytokine IL-10 to the pro-inflammatory cytokine IL-17A — suggesting that exposure to the more natural environment and dirt had stimulated their immunoregulatory pathways.

Wow – how amazing is that?!