A new study has been released by Ohio State University shows that exposing babies and young children to livestock (such as farm animals) can actually improve their immune systems.
The study specifically presented evidence of the immunological benefits of the exposure arises from the gut microbiome. Now, this may not come as a surprise given the fact most of us know that people who are exposed to more germs tend to have better immunity.
In studying two groups of infants aged six months to one year, scientists examined the bacteria and microbes inside the intestines of five Amish babies and five city babies from Ohio who had never been around livestock. The differences they found not only showed a variety between the groups, but they showed a link to respiratory immune health.
Published in the journal Frontiers in Immunology, the study showed that there were a lot of healthy bacteria in the Amish babies' guts that were absent in the babies who live in the city. The researchers pointed out that this was to be expected given the Amish babies are raised in a non-sterile environment, whereas the city is all about sanitation.
"Good hygiene is important, but from the perspective of our immune systems, a sanitized environment robs our immune systems of the opportunity to be educated by microbes," says one of the authors, Zhongtang Yu who is a professor of microbiology. "Too clean is not necessarily a good thing."
Another author, Renukaradhya Gourapura, confirms that "the priming of the early immune system is much different in Amish babies, compared to city dwellers." The study aimed to find out what the future effects would be and if the Amish babies would be able to fend off a wider variety of viruses and bacteria, in addition to lowering their chances of allergies and immunodeficiencies.
Gourapura goes on to explain that the chances of the babies developing asthma are also decreased when a stronger immune system is established early on. Science Daily refers to this as the "hygiene hypothesis", "which is built on the idea that hyper-clean modern life-- think antibacterial soap, ubiquitous hand sanitizer and scrubbed-clean homes and workplaces-- has led to an increase in autoimmune and allergic diseases."
After taking samples from the groups of babies, the researchers transplanted fecal matter into the guts of newborn pigs to see if they benefited from the surplus of bacteria. "We wanted to see what happens in early immune system development when newborn pigs with 'germ-free' guts are given the gut microbes from human babies raised in different environments," Gourapura says.
In examining the newborn pigs, the researchers saw an increase in lymphoid and myeloid cells (essential immune cells) in the pigs who received transplants from the Amish babies. The researchers concluded that the gut microbiome has a huge effect on the immune system, a conclusion that may lead to the development of gut aids, such as new probiotics, in the future.