Posts for tag: hygiene hypothesis
Image credits: Pfizerpro.com and A.D.A.M. October 2012
Is it conceivable to believe that an individual can be too clean for their own good? Maybe.
We know that the immune system in all mammals- a group that includes humans too, has an adaptive capability that matures and becomes more savvy as the challenges mounted by invading germs are responded to over a lifetime. Basically, “the troops remain battle ready when they are continually fighting and winning”. This has been cast as a potential mutually beneficial relationship for the body and the invading germs in a theory proposed to explain the rising trend of allergy and immune system mediated diseases called the ‘hygiene hypothesis’. This theory maintains that living in very clean and hygienic environments robs one of the exposure to microbial organisms which are beneficial for the maturation and ability to distinguish invaders from what belongs to the body. An abnormal maturation process involving the immune system’s cells and antibodies may then arise and predispose individuals to varying levels of abnormal immune responses which manifest in various disease forms.
Needless to say, this is still a theory and not validated as a scientific fact yet. Researchers from the University of Michigan School of Public Health observed a pattern corroborating another aspect of this theory, more amenable to scientific scrutiny. They examined data from the National Health and Nutrition Survey (NHANES) for the period 2003-2006. Two common environmental toxins, Triclosan and Bisphenol A both of which have known effects on the delicate balance of the immune and hormonal systems respectively in the body were looked for in patients aged 6 and older who also had diseases attributable to immune dysfunction for example, Hay fever. Their findings published online in November 2010, showed a relationship between having high levels of this Triclosan in the body and immune dysfunction associated disease. Triclosan, is an antimicrobial agent and is ubiquitous in the home environment. Diapers, antibacterial soaps, and toothpaste are some household items that contain this product. The higher levels of Triclosan seen in these patients may have sufficiently altered the population and type of microbes that these individuals would have been normally exposed to and therefore led to abnormal maturation of their immune system over time and subsequently modified their overall immune response and foster the development of allergy related disease states. This writer has observed trends not subjected to scientific testing at any level yet, in children of first generation West African immigrants born in the USA (Bronx NY) who go on to develop varying levels of allergy symptoms which are mediated at many levels by immune dysregulation. The parents of these patients demonstrate no such problems and a cautious assumption may be to say their earlier childhood exposures in the developing world to different microbial agents in childhood may have fostered a proper maturation and development of their immune systems, i.e the troops (immune cells) remained battle ready and matured as anticipated. This perhaps fostered the innate ability of the immune system to distinguish self from non-self and keep the focus on the invading germs.
As we push the frontiers of medicine daily in the 21st century, some of these basic questions remain unanswered and beg for more research and elucidation of the facts. Until then, we will keep the hygiene hypothesis in the realm of hypotheses and continue to take all necessary precautions for clean, safe healthy skies, water, air, soil, food and above all planet. Louis Armstrong’s timeless classic, still chimes, “what a wonderful world”.
The information here is for patient health education purposes only and is not intended to serve as or replace the advice of a physician, please consult your healthcare provider as appropriate.