In societies where hygiene has become dominant, one school of thought suggests we are now suffering poor health as a result. What we tend to think of as ‘dirt’, is likely to be very much more beneficial than we realise.
Researchers describe our bodies as ‘microbiomes’; home to bacteria and other microorganisms whose number vastly exceeds our own cells. The sheer weight of these organisms within could be 3 – 4 pounds. Having evolved in the wider biome of the world around us, our bodies grew to live with the comings and goings of surrounding bacteria. In the process, we may have become dependent on the functions they play in our internal systems.
The Human Microbiome Project states: they produce some vitamins that we do not have the genes to make, break down our food to extract nutrients we need to survive, teach our immune systems how to recognize dangerous invaders and even produce helpful anti-inflammatory compounds that fight off other disease-causing microbes.
Studies are underway to see whether our practices of hygiene are unduly diminishing our stock of these health-giving bacteria. At the onset of life babies gain bacteria as they emerge through the vagina. C-section births miss out on this. Later on, antibiotics may kill off some useful bacteria while attacking the disruptive ones. And throughout life, regular hand washing may disrupt the constant pathway of bacteria coming in and going out.
Various impacts of diminished microbiomes are being investigated, not least the causes of obesity. But this science is yet young. We do not yet know how substantial an impact our microbiomes have on our health.
And this presents us with a problem. We still have choices to make. Should we wash and disinfect as regularly as we do? What are the possible downsides of taking a particular course of antibiotics? In the risk-averse culture of child-birth, how do we respond to a recommendation for a C-section?
Where there is a likelihood of infectious disease, then we shall no doubt be advised to wash diligently. Where there is not, as is so ordinarily the case, then we might want to think afresh about ‘dirt’, and live well with it.