Can Germs Actually Be Good For You?
Have you ever wondered why you feel more calm enveloped by trees instead of high rise buildings? Or why a walk in a park can brighten your mood? Growing up, I was constantly surrounded by trees and grass, always playing make-believe and climbing everything in sight. Looking back, the time I spent being connected with nature felt simpler and happier than the high stress and urban life I’m living now. It wasn’t until I moved to Minneapolis and started living in dense apartment housing that I truly appreciated my childhood. I had daily access to large stretches of green space where I had the freedom to get my hands dirty and explore the great outdoors. In a world where we spend 90% of our time inside, scientists are starting to connect getting outside and interacting with nature to a myriad of health benefits including an increase in memory, improved mental health, lower blood pressure, and a decrease in cancer risk. Some scientists have taken it a step further, connecting children’s interactions with the microbes in the soil as a direct link to decreasing the likelihood of autoimmune diseases and allergies calling it the “Hygiene Hypothesis”.
So what is the Hygiene Hypothesis? This theory was first stated by David P. Strachan, a British professor of epidemiology, in the late 1980s. He discovered a negative correlation between the number of children in a household and the instances of hay fever that arose. Households with more kids had less instances of hay fever because of the spread of germs among children. Exposure to germs at an early age strengthens children’s immune systems because they build up a tolerance. All throughout my childhood I would be told to wash my hands before I eat anything or to never put anything in my mouth or near my face, but apparently that wasn’t always a good thing. Modern life emphasizes sterile environments and the necessity to keep everything clean. Now, scientists are stating that an introduction to microbes early may be the key in determining the susceptibility to autoimmune diseases and allergies later on in life. As humans evolved, so did our connection to the microbiome in the soil we interact with everyday. These ‘old friends’ have helped to calibrate our immune systems to fight off harmful pathogens without attacking harmless contaminants like pollen.
However, a balance is required to prevent infections from contaminants like E. coli and salmonella. Rob Knight, a professor at the University of California and co-founder of the American Gut Project and the Earth Microbiome Project, states that:
“You still shouldn’t challenge your kid’s immune system by encouraging them to eat tainted meat, lick a hospital floor, approach a rabid bat, or otherwise expose themselves to likely harmful microbes — but the modern hygiene hypothesis says encountering good microbes via dirt and contact with healthy, diverse people and animals may be good preventive medicine.”
With the world population ever increasing and more people living in cities than ever before, more kids are being raised in apartment complexes and high density housing with little to no yard space. Continuous restriction, sterilization, and lack of outdoor space can do more harm than good. By encouraging kids and adults to interact with nature and each other, our immune systems can be improved along with a multitude of other benefits.
I have seen these benefits in my own life this semester through the HECUA Environmental Sustainability program. This program has offered me a chance to get back outside through field experiences and overnight farm stays which have given me invaluable opportunities to reconnect with the environment and immerse myself in nature. The earth does more for us than we thought and interacting with it on a daily basis can truly improve our lives. So get outside, visit your local park, and support more urban green spaces; you may just improve your health along the way.
