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Overly Sanitized Environments Lead to Poor Health?
bignickel writes "A recently-released study examined the health implications of living in an overly hygienic environment. According to the 'hygiene hypothesis,' living in such an environment early in life can lead to problems with allergies and autoimmune diseases. The study compared lab rodents with rats and mice living in the wild. Time to stop Lysol-bombing the house?"
My mother was stricken with Polio in the early 50's, just a few years before the vaccine was approved.
Although I've never seen any literature that support this, she says Polio was known as a Middle-class disease, since the middle-class were more likely to have cleaner houses (thus not exposing babies to as many germs and developing healthy immune systems). The fact that her mother was a clean-freak before and after my mother was born may be coincidental to her contracting Polio, but I like to think they're related.
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2B1ASK1
I often work inside a clean room, and once I saw a colleague of mine have a severe hay fever attack in there. Tears streamed from his eyes etc. He had to sit down for a while to recover. He told me it's the change of environment (in this case from dirty to clean air) that did it for him. Very strange.
-- Cheers!
"A totally sanitised environment is no problem to be raised in as long you are going to continue living in it forever"
Untrue. There are more problems with an untrained immune system than just the fact that it won't strengthen. At the low end of the scale are allergies, where you develop an immunoresponse to things that aren't actually dangerous, and have to start avoiding certain foods that you'd otherwise be able to eat. At the other end of the scale are autoimmune problems; where the immune system starts to attack you itself. I recall a case of a guy who's immune system was attacking his own intestines. They countered this by (yeah, I know) giving him *worms*, so that his immune system would turn against them instead, and, being occupied, allow his intestines to heal.
You immune system also fights many other things other than just outside invaders, such as cancer, which is a lot more common than you might think, but most of the time the immune system can take care of it and so it's not a problem.
So no, proper immuno development is essential, even if you can live in a sterilised environment all your life.
The revolution will not be televised... but it will have a page on Wikipedia
Like you said, that is your *personal* experience.
Whereas I grew up just as you did, playing outside, lots of different animals, hay, etc. Not a Lysol environment at all. And then around 10 years old, while making tunnels and forts in a big pile of haybales with friends I got hit with the hayfever. Around the same time I developed an allergy to cats. My father is exactly like this and his father is as well (allergic to cat dander and have hayfever).
Oh, and you can be born with allergies. I'm allergic to penicillin - given some as a newborn and developed a rash (apparently a common allergic reaction to it).
I'm sure that there are others that can refute your hypothesis.
But I still believe that it is good to not grow up in a sterile environment. I'm not thinking about allergies, but just about having an immune system that gets some exercise and building up a catalog of antibodies that can respond to similar threats. (in fact, isn't the allergic reaction your immune system's response to that allergen?)
It could also be that those with allergies tend to move away from the farms. I wouldn't last a week on a farm without some Zyrtec.
My sister and I grew up in the same environment. We lived in air conditioning, but spent most of our childhood playing outdoors in suburbs of Minneapolis. I have severe pollen-based allergies. If I do not have air conditioning or medication, I can wake up with my eyes glued shut from secretions, my throat can hurt like the worst strep throat you ever had, and my eyes and ears itch constantly. I am also mildly allergic to pretty much every food. My sister has no allergies of any kind.
My family was on the farm two generations ago, and one generation ago they still worked on the farm during the summer. Some of them have allergies, some don't.
My daughter's skin has reacted to certain foods since she was a baby.
So, I think there are probably genetic predispositions to allergies. However, I think there may be a role for environment in those who are less severely predisposed to allergies than the members of my family.
Intuitive: I figure your immune system is like anything else in your body -- if it doesn't get a regular workout it becomes less efficient and when you stress it, it may behave unpredictably.
Anecdotal: I grew up playing outside a lot. My favorite thing to do was hydraulic engineering on mud-puddles. I built dams, canals, locks with gates, stirred up mud to see how it behaved, etc. I was out in the woods a fair bit, got the occasional tick (this was before Lyme disease was such a concern, and as long as you caught the ticks the same day, Rocky Mountain Spotted Fever was nothing to worry about). We had cats, our relatives had dogs, etc. To this day I have relatively little issue with allergies or illnesses of any kind. Yes, dust makes me sneeze, but it honestly puzzles me why people stampede to get flu shots every year -- I've had the flu maybe twice in my life, it sucked, it lasted about three days each time, and I got over it. People look at me like I'm nuts -- "You're not getting a flu shot? WHY NOT???"
On the other hand, just about all the people I know with allergies, constant colds, etc. are the ones with a horror of anything that might be less than perfectly fresh and germ-free. I drink milk that's a few days past the sell-by, I eat stuff that's been in the fridge a couple days, I have lunch at greasy spoons where the kitchen staff maybe doesn't wash their hands every time they touch their own face. I don't go out of my way to find "dangerous" food or items, but neither do I avoid things that may have tiny amounts of "harmful" stuff on them like my life is at risk every time I eat a sandwich.
Logical: I won't use antibacterial soaps unless there's no alternative. Why? Because using them indiscriminately breeds resistant bacteria. This is just logic backed up by known scientific observation of microbial evolution. It's the reason your doctor won't (or at least, shouldn't) prescribe you antibiotics every time you have a fever -- if it's not bacterial, the drugs wouldn't do you any good and would breed resistance in bacteria that aren't causing you any issues yet. Then those resistant strains would take over and now you have a problem, and it's a tough problem because the doctor has to give you massive doses, or use a different antibiotic -- and there are only so many antibiotics out there. Trying to sterilize the environment is the same thing on a grander scale.
If more parents let their kids go ahead and, for example, chew on the cat's tail, the kid's immune system would get exposed to a few new agents (and learn to deal with them), and the cat would swat the kid who would then learn "don't chew on kitty, it hurts". That's two problems solved. Don't let them play in raw sewage, but don't keep them in a plastic bubble either.
-- Old Man Kensey
I have a similar experience to yours. I was diagnosed as being allergic to pollen, animal dander, dust of any sort, and so on. My mom protected my brother and I from those things like crazy. When I was in the presence of a cat for example I would have a hard time breathing and my eyes would swell up and water like crazy. But guess what? After my sisters started adopting just about every stray or orphaned animal they found my reactions to them became less and less untill completely gone. At one point our house was like a petting zoo with all kinds of animals we were nursing back to health and/or rasing. The family doctor was very interested in what happened with me. At that time they were conducting a study into the theory of prolanged exposure to allergens can can help lessen or completely remove the allergic reactions. After that my parents started sending me to summer camp and again guess what? After the first 2 summers my allergic reactions to pollen were gone as well. Dust still makes me prey for death but that is the only allergy I haven't been able to shake. So yeah it's my own personal exp but I have spoken with MANY people with similar exp. Now my younger brother was not so lucky. He got the same exposure as I did but his allergies never went away. But they did decline noticably during the zoo period or our lives. But that only lasted until we left home. They have in fact gotten stronger over the years. So who knows. There needs to be more study done on this but I know in my case exposure did seem to cure me of most of my allergies.