Sunday, 16 October 2016

The bacteria that don't kill you will make you stronger

Tetanus, typhoid fever, diphtheria, syphilis, cholera, leprosy and tuberculosis are among the diseases spread to humans by bacteria - microorganisms, around 0.001mm in length, pathogens that can kill humans. Better hygiene and antibiotics have saved many billions of lives since the microbe was discovered in the mid-19th Century.

Yet last month, the US Food & Drug Administration banned the sale of antibacterial soaps. This is the result of research conducted since 2013, suggesting that they might affect natural resistance to bacteria. Not just in our own bodies; flushing this stuff down the drain via wastewater treatment plants, it eventually enters the wider environment where it can increase bugs' genetic resistance to antibodies by natural selection.

From childhood, we've had it drummed into us that bacteria, along with viruses, are a danger to our health, yet the reality is that our relationship with bacteria is far more complex. The human microbiome [this Wikipedia page is well worth reading], consists of bacteria, viruses, fungi and archaea, the last being until recently considered a form of bacteria, now known to be something quite separate. Let's look at the bacteria...

There are between three and ten times as many bacteria living within and on us than there are cells in our bodies. Wow. If you scrape together all the bacteria on this planet, they will weigh in total more than every animal and plant put together. We inhale and exhale, ingest and excrete them in vast numbers; bacteria and us - we symbiose in a general equilibrium with one another.

The hygiene hypothesis suggests that as we evolved into mammals then on into humans, we spent a lot of time in the mud and rotting vegetation, from which we picked up many microorganisms that formed a symbiotic relationship with us, either immunising us, or killing the weaker individuals. But since higher standards of hygiene have spread around the world, our bodies have adapted accordingly. Studies of epidemiological data have shown that various immunological and autoimmune diseases are much less common in the developing world than the industrialised world.

Are we obsessing too much with being germ-free?

An article about former UK minister Michael Heseltine (83) and his garden piqued my interest. Here's a man who had a serious heart attack 23 years ago - and today, this octogenerian seems to be in splendid fettle. The health-giving properties of gardening... yes - I read about this somewhere... Turn to Google... [Short aside - these days, there's no excuse for ignorance other than a lack of curiosity. 'Can't be googled' = intellectual laziness. If you're curious, you can find out more, faster, than ever before in human history. And double-check it. Make sure you're not merely reinforcing your prejudices.]

And I find plentiful articles on the subject. Let's take this one: headline: It’s in the Dirt! Bacteria in soil may make us happier, smarter. "A strain of bacterium in soil, Mycobacterium vaccae, has been found to trigger the release of seratonin, which in turn elevates mood and decreases anxiety. And on top of that, this little bacterium has been found to improve cognitive function and possibly even treat cancer and other diseases." Injecting M. vaccae into cancer patients was found to alleviate symptoms, and improve emotional health, vitality, and even cognitive function. So soil bacteria is good for the samopoczucie (another candidate for a loan-word in English - 'the way your mind and body feel').

It would be hypocritical of me to commend gardening to my readers, as I don't do a hand's turn of it myself, but I do a lot of semi-rural and rural walking, stirring up the biome beneath my muddy boots or breathing the dust kicked up beneath me on dry footpaths in summer.

We need to get the balance right. We shouldn't flood our kitchens and bathrooms with antibacterial sprays and soaps, nor should we live in filth and abnegation. A conscious approach to these matters is all important.

This time four years ago:
Hello, pork pie!

This time This time two years ago:
The meaning of class - in England, in Poland

This time five years ago:
First frost 

This time nine years ago:
First frost 


Gordon Hawley said...

George Carlin - Germs, Immune System

Michael Dembinski said...

@ Gordon Hawley:

At least he didn't die of food poisoning! :-)