Allergy Study

I came across this on the drive in to work yesterday morning, and it reminded me of just a few short years ago.  From time to time I would babysit my godson, and for quite a while, he used a pacifier (which I always call a "binky").  Like many babies and very young children, he took comfort in a pacifier.  It was often the "go-to" thing at bedtime or when he was fussy.  When babysitting, the pacifier would inevitably fall from his mouth and land on the floor.  More often than not, I would see it happen, pick it up, make sure there was no dog hair or big chunk of dirt on it then pop it back in.  I can hear a few people gasping, but generally speaking, "dirt don't hurt" was a saying that my brothers and I practiced on a daily basis as children. My one brother's nickname was literally "dirt" since he was generally filthy from playing outside so much.  This is all a bit circuitous, but it leads me to two things, the hygiene hypothesis and a recent study published in Pediatrics.

While my approach in cleaning the pacifier is probably not taken by many, this recently published study I mention focuses not only on how parents cleaned their children's pacifier but also how it may impact the development of eczema and allergies.  In examining 184 children, researchers studied what the children were sensitive to, how parents cleaned their pacifiers, and analyzed the bacteria in the children's mouths.  At 18 and even 36 months, children whose parents cleaned their pacifiers by sucking on them, showed remarkable protection against eczema and asthma.  Yes, you read that correctly.  Some parents clean their child's pacifier by sucking it clean then giving it back to the child.  Odd as it may sound, this is believed to be the key findings of the study.

Regardless of how "clean" we, as a species, think we are, there are literally billions of bacteria living on and even inside of us.  On our skin, in our digestive tracts and in our mouths, bacteria play a very important part in everything from our immune system to the way in which we break down our food.  The theory is that by sucking on the pacifier the parent not only cleans visible dirt or debris from it, but they actually place bacteria back onto it.  That bacteria is then introduced to the child, exposing the child's immune system to a broader array of bacteria.  This ties into the hygiene hypothesis in that many believe children in western societies are "too clean," and because of this, are at an increased risk of developing things like eczema, asthma or allergies.

When we are infants, our bodies' systems are developing.  Think of the immune system like a defense mechanism that is untrained.  By nature, this system is designed to find things harmful to us and fight them, so at a very early age, the immune system is trying to determine what is dangerous and what can be ignored.  The hygiene theory suggests that lack of exposure to a variety of bacteria and germs means the system doesn't get thorough training and often identifies innocuous substances as harmful.  "Well, we have to find the shady characters to defend you against, and I don't like the looks of these guys." So when they immune system cannot find real enemies, they start identifying harmless substances as dangerous.

The hygiene hypothesis is just that, a hypothesis, and there are some studies that run counter to this.  This piece of research, though, suggests that there is some validity to it.  While it is too early to suggest that parents start sucking on their kid's pacifier to clean it, it really can't hurt.  Oh, and just for the record, most parents simply rinse the pacifier.  I guess I all into that "other" category.

For an abstract of the pacifier study.

Author: KevvyG

Like many health issues and conditions, the primary determining factors are genetics and the environment. Both are not weighted equally in any given situation, but both play a role in the development of most medical conditions and diseases. Even when the specific causes of a condition, like allergies, asthma and eczema, are unknown, evidence is strong that these two factors are important. A recent study published in The Journal of Allergy and Clinical Immunology suggests a very strong link between parents with allergic diseases and the chances of their same sex offspring in developing allergic diseases.

Using a combination of IgE blood tests, skin prick tests and close examination of parental history, researchers studied parents and monitored their children for their entire childhood. In collecting and analyzing the data they found that when a mother had asthma or eczema their female children demonstrated a nearly 50% increase in the risk of developing that same condition. The same was not true for male children. However, this a near identical increase in risk was seen when examining paternal conditions and their male offspring. Simply put, if a mother had asthma or eczema, her daughter was 50% more likely to develop the same condition. Her son, saw little to no appreciable increase in risk. If a father had asthma or eczema, his son was 50% more likely to develop the same disease while his daughter was not.

This is important for two reasons. In the more long term, it more clearly defines the genetic link between parents and children when it comes to allergic diseases. The genetics behind conditions like eczema will ultimately be key in preventing them. In the short term, because this link has been more readily defined, it could make it easier in the future to diagnose allergies and eczema. Patient history is a critical factor in determining asthma but even more so for allergies. Blood and skin prick tests can show sensitivities but it is not until a doctor sees the full picture of the patient's medical and family history that a most accurate diagnosis can be given.

To read an abstract of the study.

To view eczema friendly personal care products.

Author: Kevin Gilmore

As the prevalence of asthma and allergies continues to climb in most Western societies, the causes of these chronic conditions are still not known. Though, with a collection of news stories, research pieces, and press releases coming in over the last couple weeks, the 'Hygiene Hypothesis' on allergies is only looking stronger. Of these, the most prominent were studies that examined Finnish children and another that took a look at Amish children in Indiana and the link between growing up in more "natural environments" and a predisposition for allergies and asthma.

In the Finnish study, 14-18 year olds were tested to compare how many and what kinds of bacteria, particularly gammaproteobacteria, could be found in and on their bodies. This data, when compared to the type of environment they grew up in, showed that children who had grown up and lived in more natural environments (read, less urban; more trees, less asphalt), showed a greater diversity of these tiny bacteria in their skin. They were also LESS likely to suffer from allergies.

Though the second study was very general in nature, in comparing Amish farm children with Swiss farm children and Swiss children who did not live on farms, they found that children not on farms had the highest rates of asthma and allergen sensitivity. Swiss children on farms had lower rates of asthma but the same sensitivities to allergies; and Amish children on farms had the lowest rates of asthma and sensitivities to allergies.

While neither study is a smoking gun, solidly proving the Hygiene Hypothesis, both lend at least some measure of support to the idea that the more sanitized the environment we grow up in, the more likely our immune systems are going to go haywire around harmless substances, like pollen, pet dander and dust.

As someone who grew up in a very rural part of Ohio, my siblings and I have experiences that fit this theory. Having spent much of my childhood on our family farm, playing in the woods, or chasing chickens, there are few instances outside of school where any of my sibling and I were "clean." My father literally nicknamed my one brother, "Dirt". To this day, none of us three older boys have any problems with allergies or asthma, despite a family history of the latter.

While surely it is anecdotal, my two youngest siblings both suffered from asthma. Between us three elder boys and the younger two, there is nearly a 13 year gap. My youngest brother and sister did not grow up as we had. The amount of time they spent inside as children was inconceivable for us older three. In the summer, it was fairly common for the doors to the house to be locked. And why not? We had eaten breakfast or lunch. We lived off a dirt road and generally saw two vehicles pass by every day. We had a spigot outside, and air conditioning isn't cheap when you have three kids running in and out all day long.

So while the two youngest children in my family enjoyed the convenience of air conditioning, Playstation and Wii, the dirt, germs, and farm life likely served our immune systems better.... which I think is only fair considering the hundreds of rows of carrots, corn, potatoes, and peppers in our family garden that three older boys weeded throughout our childhood. To date, the youngest two siblings pulled weeds out of exactly zero rows of crops in the garden.

Abstract of the Finnish Biodiversity & Allergies Study.

Indiana Study of Amish and Asthma & Allergies.

A study released in this month's issue of the Journal of Leukocyte Biology suggests that some instances of asthma may be related to what could be classified as an allergic response to bacteria.

The allergic response, though not fully understood, is often fairly simple. When protein allergens like pollen, dander or dust mites enter airways and bind to IgE (Immunoglobulin E) receptors, mast cells release histamines which cause the swelling and inflammation. These are often what are behind the sneezing, congestion, and watery eyes.

For this study, researchers introduced Pseudomonas aeruginosa, a common infection causing bacteria, in to mice. In response to this foreign bacteria in the lungs, white blood cells produced very high levels of histamine.

While histamine production in the lungs is not uncommon (histamines cause the most common symptom of asthma - inflammation) what is most significant is that it was produced by white blood cells, NOT the mast cells that produce histamines in allergic responses.

This study further complicates the blurry line between allergic and asthmatic responses, by showing that a common bacteria can cause white blood cells to exhibit allergen response-like traits. Ultimately, studies like this not only shed more light on the processes underlying these responses but can also lead a better understanding of how the body can combat allergies and asthma.