Previous research has shown that early exposure to potential allergens and pathogens – such as growing up on a farm – trains the immune system not to overreact, leading to lower rates of asthma and allergies. A new study suggests that Amish children who grow up on farms have even lower rates of asthma and allergies than other children raised on farms, according to theNational Post.
The researchers compared allergy rates between Amish children raised in northern Indiana on rural farms and kids raised on Swiss farms. Dr. Mark Holbreich, lead author of the study, commented “The rates are very, very low” among both groups. However, the rates are even lower among the group of Amish kids.
It is unclear exactly why growing up on a farm – and an Amish farm in particular – seems to prevent allergies. The “farm effect” is well-known in central Europe, but less research has been done on American farms. Dr. Holbreich, an Indianapolis allergist, says that he noticed that very few people in the Amish communities in Indiana had allergies. After reading studies on the “farm effect” in Europe, he wondered if the same phenomenon could be found in Indiana’s Amish communities.
Many Amish families can trace their ancestry back to Switzerland, making the comparison between their farms and Swiss farms a natural choice. The researchers surveyed Swiss farming families, Swiss families who do not live on farms, and Amish families. They found that just 5% of the Amish children had asthma, compared with 6.8% of Swiss kids living on farms and 11.2% of other Swiss children.
The theory is that early exposure to the types of allergens and pathogens typically found on a farm trains the immune system to recognize them. Dr. Holbreich says that as for why the rates of allergies among Amish children are even lower than other farm kids’ allergy rates, “that piece of the puzzle we really haven’t explained.”