“Girls tend to be dressed more in clothing that is not supposed to get dirty, girls tend to play indoors more than boys, and girl’s playtime is more often supervised by parents,” said Clough, adding that this is likely to result in girls staying cleaner. “There is a significant difference in the types and amounts of germs that girls and boys are exposed to, and this might explain some of the health differences we find between women and men.”
One daycare center in Portland has taken the study to heart, as they encourage both boys and girls to play in the mud. The Portland Providence Wee Care Day Care Center provides a pair of rubber boots, shovels, and a mud box for their kids to play in. As Wee Care director Colette Brown explained, "We always tell parents the kids are going to get dirty. That's part of the work of childhood.”
You can learn more about Sharyn Clough's research on Oregon State's website.