Being raised in an environment that is too clean could put children, especially girls, at increased risk of developing chronic conditions such as asthma, allergies and autoimmune diseases, finds a study published in the journal Social Science and Medicine.
Philosopher Sharyn Clough with the Oregon State University looked at why more women are affected by these chronic conditions than men, and her findings suggest that it may have to do with the levels of hygiene as a child.
"Girls tend to be dressed more in clothing that is not supposed to get dirty, girls tend to play indoors more than boys, and girls’ playtime is more often supervised by parents… 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," said Clough.
The idea of a link between childhood hygiene and chronic conditions is nothing new: scientific studies have been exploring the idea since 1997.
Currently, a popular hypothesis is that these conditions occur when the developing immune system is not given enough to do, and therefore is not trained to tell the difference between "good" and "bad" foreign bodies, causing it to attack at random.