Nadine Ivester
Mrs. DeShaun Williams
Biology 275
1 February 2015
Believing The Hygiene Hypothesis?
What is the “Hygiene Hypothesis”? I had never heard of it. The theory suggests that humans exposed to germs at a very young age may prevent a serious illness and/or allergies from forming as an adult. In today’s society, people remove germs from themselves with the use of daily disinfectants, bleach, sanitizers, etc. Although this habit is believed to be a good one it may have negative consequences. Studies have been conducted and continue to research how microorganisms, both good and bad, affect the health of humans and to determine what is a healthy balance between the two groups of germs. I was surprised to learn there is an association and communication between the flora in the gut and the brain. This association may be linked to eating disorders and depression which are illnesses that exist in my family. So I am excited to learn more about this topic.
The “Hygiene Hypothesis” was first formulated by David Strachan in 1989 (Adler, Interlandi 148). He stated that exposure to childhood illness’s gave children an immunity-like effect against some adult diseases. The human body is covered with millions of bacteria, both inside and on our skin. “There are thousands of different species, found in combinations ‘as unique as our DNA or our fingerprints,’ says Stanford biologist David Reman…” (148). Disruption to the exposure of bacteria, whether by over-cleanliness of our physical self and our environment and to disrupt the flora inside our bodies with the overuse of antibiotics and poor nutrition, will affect the bacteria and ultimately our health. “The microbes we have had all our lives are the ones that colonized us in the first weeks and months after birth, while our immune system is still undeveloped; in effect, they become part of the landscape…But to develop properly the immune system must be exposed to a wide range of harmless microbes early in life” (150). A study conducted by researchers at the Brigham and Women’s Hospital gave support to the hygiene hypothesis. They bred and studied germ-free mice and exposed them to microbes early during their first weeks of life. When these mice became adults, they exhibited a normalized immune system and a prevention of disease as opposed to the germ-free mice not exposed to microbes as babies but later as adults. “Moreover, the protection provided by early-life exposure to microbes was long-lasting, as predicted by the hygiene hypothesis…’These studies show the critical importance of proper immune conditioning by microbes during the earliest periods of life,’ said Ricard Blumberg, MD, chief for the BWH Division of Gastroenterology, Hematology and Endoscopy, and co-senior study author, in collaboration with Dennis Kasper, MC, director of BWH’s Channing Laboratory and co-senior study author” (Brigham Women’s Hospital 1).
There are theories that propose that “as modern medicine beats back bacterial, viral and parasitic diseases that have long plagued humanity, immune systems may fail to learn how to differentiate between real threats and benign invaders, such as ragweed, pollen or food” (Stein 152). Rats that were born and raised in a sterile laboratory exhibited a more sensitive immune system than those bred in the wild and were exposed to different kinds of bacteria and microorganisms. Children who grow up on farms, with pets or even with older siblings did not have frequent allergy outbreaks (152). Both of my daughters have allergic reactions to penicillin, due to the frequent ear infections and antibiotic treatments as children. Their physical side effects of taking penicillin was the outbreak of hives all over their body. The worry was anaphylactic shock and death. As adults, when they get sinus infections or any bacterial infection, the prescribing physician has a challenge as to what antibiotic to give them.
The connection between bacteria and body composition and