here is one of the excerpts okie...
Dr. P's Pediatric Journal Club
The study
These Dutch researchers measured levels of dust and bacterial and fungal toxins (potential "allergens") on the living room floors of 700 three-year-olds with allergic moms.
They classified exposure to these allergens as low, moderate, or high.
They then followed the kids for 4 years, looking for the development of doctor-diagnosed asthma and allergies.
What the study found
Children with high exposure to dust and mold at 3 months were significantly less likely to have developed persistent wheezing by four years of age.
Children with high exposure at 3 months were less likely to wheeze occasionally, but this outcome was not as pronounced (and not statistically significant).
Children with high exposure at 3 months had lower allergic antibodies (IgE) to one of the fungi.
Dr. P comments.
Why do farmers' kids have fewer allergies and asthma? Why has the prevalence of allergies and asthma increased, even as we conquer ever more infectious diseases? This study adds to the mounting evidence that the exposure early in life to a very clean environment (low on dust and various bacterial and fungal toxins) may play a role.
Here's the theory: The newborn immune system is tolerant and non-allergic to most anything (which is why it sometimes does such a lousy job of fighting off infection). When it is exposed to the usual allergy-causing antigens (such as dust and mold and dogs and cats), the immune system and allergens become lifelong buddies: a long-lasting acceptance and tolerance between them develops.
On the other hand, when an allergy-prone infant is raised in a very clean - almost sterile - environment, the immune system remains unfamiliar with these allergens. Then, when exposed later on, it reacts to them as it would to any alien invader, triggering allergies and/or asthma.
What does this mean?
Sloppy parents of the world stand tall! Your kids may have fewer allergies than will those of your hyper-sanitary peers!
Even if there is a family history of allergies and/or asthma, I think it's too early to actually recommend a little extra dust and mold in your baby's bedroom. But I do hope this information will help parents to overcome their messiness/germ phobia and free you to lighten up on obsessively trying to 'sterilize' your infant's world from all germs and dirt and crud.
Hey, life is messy. This study suggests that maybe that's not such a bad thing after all!
A caveat from Dr. P: It may be true that early exposure to mold and dust and cats, for example, will prevent allergies to them later on (in an already susceptible child). However, once that allergy has been established, the horse is out of the barn: cleanliness and even catlessness, etc. are then very important to prevent significant symptoms.
