A small experiment carried out in some daycare centers in Finland was able to change the immune system of some children. The interaction of the little ones with undergrowth for only a month gave unexpected positive results.
The study began when daycare centers in Finland rolled out a lawn in the playground areas, planted undergrowth, such as dwarf heather and blueberries, and allowed children to take care of plants in planting boxes.
The study compared the environmental microbes found in the backyards of 10 different urban daycare centers that care for a total of 75 children aged 3 to 5 years.
Some of these nurseries contained standard urban backyards with concrete and gravel, others took children for daily contact with nature and four had their backyards d with grass and undergrowth. Over the next 28 days, children the last four daycare centers had time to play in their new “green yard” five times a week.
A nursery before (on the left) and after the introduction of grass and planters (on the right). (University of Helsinki)
When the researchers tested the microbiota and intestines of children before and after the test, they found better results compared to the first group of children who played in day care centers with less vegetation for the same period of time.
Even in the short duration of the study, the researchers found that microbes on the skin and offal of children who regularly played in green spaces increased in diversity - a trait that is linked to a healthier immune system in general. Their results corresponded in large part to the second group of children in daycare centers who took daily walks in nature.
Comparing then to other children in the city, who stay in “standard urban” daycare centers without contact with natural elements, children aged 3, 4 and 5 years in these “green daycare centers” in Finland showed an increase in T cells and other important immune systems in their blood within 28 days.
"We also found that the intestinal microbiota of children who received vegetables was similar to the intestinal microbiota of children who visit the forest every day," says environmental scientist Marja Roslund, the University of Helsinki.
Some research done previously has shown that early exposure to green spaces is somehow linked to the proper functioning of the immune system, but it is still unclear whether this relationship is causal or not.
The notion that an environment rich in living beings impacts our immunity is known as the 'biodiversity hypothesis'. Based on this hypothesis, a loss of biodiversity in urban areas could be at least partially responsible for the recent increase in diseases related to the immune system.
“THIS SUPPORTS THE ASSUMPTION THAT CONTACT WITH NATURE AVOID DISORDERS IN THE IMMUNOLOGICAL SYSTEM, SUCH AS AUTOIMMUNE DISEASES AND ALLERGIES”, SINKKONEN SAYS.
The results are not conclusive and need to be verified in larger studies around the world. Still, the benefits of green spaces seem to go beyond our immune system.
Research shows that leaving home is also good for a child's vision, and being in nature as a child is linked to better mental health. Some recent studies have even shown that green spaces are linked to structural changes in children's brains.
The bond with nature as a child is also good for the future of our planet's ecosystems. Studies show that children who spend time outdoors are more likely to become environmentalists as adults, and in a rapidly changing world, this is more important than ever.