Study shows farm-raised kids may get long-term health benefits
Kids growing up on farms might be getting some long-term health benefits from early environmental exposures, according to a new study from UW-Madison.
The study, published recently in the Journal of Allergy and Clinical Immunology, was conducted by researchers from Marshfield Clinic and UW-Madison professors.
It used data from the past 17 years, comparing two distinct groups in the Marshfield Epidemiologic Study Area in central Wisconsin: 268 children ages 5 to 17 who lived on a farm for their first five years of life, and 247 children of the same age range who lived in rural areas but never on a farm.
MESA is a geographic region of zip codes split into two main sections in central and northern Wisconsin. A majority of the residents of these areas get care at Marshfield Clinic or affiliated hospitals and centers.
Farm-exposed children had significantly lower rates of hay fever, with 17 percent compared to 28 percent for non-exposed kids. Eczema rates were also lower -- 7 percent compared to 19 percent -- and about half as many farm-exposed kids had severe respiratory illnesses in the first two years of life as had the non-exposed group, with 16 percent versus 31 percent.
James Gern, a professor of pediatrics and medicine at UW-Madison, was one of the principal investigators for this study. He says the findings suggest that exposure to the farm environment or other elements of the farming lifestyle are helping these kids resist allergies and viral respiratory illnesses.
But these results alone don’t tell the whole story.
“This first study was really interesting to us. … it shows there are big effects, but it doesn’t say what those effects are due to,” Gern told WisBusiness.com.
To figure out what it is about the farm lifestyle that is leading to these resistances, Gern and other researchers are pursuing a second study seeking to examine pediatric health at an even earlier stage.
This will take more in-depth examination than the first study, which entailed looking at health records and having conversations with individuals and their families. The prospective birth cohort study, known as the Wisconsin Infant Study Cohort, involves enrolling mothers before their babies are born so as to study exposures right from the start.
Though concrete answers are still a few years out, Gern says some think the health benefits are related to contact with animals and the biologically “rich” environment that farms present.
“Animals, plants, microbes, bacteria, fungi… we think of some of these things as bad, but a number of them are probably helpful in emulating the development of the immune system,” Gern said. “Those are the things we are studying.”
He added that health benefits could also be due to other things like varying diets or higher levels of exercise and outdoor time.
“We’re casting a broad net -- we will probably find a number of things,” he said. “The goal is, if we can identify specific things, we can think about how we’re raising kids in other environments.”
Gern says there’s lots of work to go on the second study, but early results show that kids raised on farms have different types of bacteria living on their skin.
“Within the next few years, we will have the first results that were planned in the original study, to see if kids on farms have distinct patterns of immune system development and specific illnesses,” Gern said. “In the next few years, initial results will be completed and we will be confident about those answers.”
Findings from this continuing research will be combined with data from 11 other cohorts as part of the National Institutes of Health’s ECHO program, Gern said.
The Environmental Influences on Child Health Outcomes program compiles data from around the country, comparing and contrasting rural data with information on people in urban environments and other settings.
“By putting all this info together, we should get a good picture,” he said.
--By Alex Moe