In an unimaginably vast universe, imagining ourselves as too important has been a persistent and visible sign of human folly. At various points in history, someone or the other has fantasised us being the epicentre of the cosmos or the acme of evolution, precarious notions later challenged or debunked by science. So when popular science writer Jonathan Turney says humans are “super organisms”, it certainly cannot be another pat on our ego.
It is “just a convenient word”, Jon says, to get the idea across that we are no island, that we are a creature made up of trillions of microbial life forms that live within us. “The 100 trillion bacteria in our gut alone outnumber the total number of cells in the human body,” he explains putting some staggering numbers into perspective. These invisible microbial lives, mostly bacteria, yeast and fungi, which inhabit us, seem to be intimately involved with our physiological and even mental functioning. That makes these miniature life forms important and fascinating for us to study.
Research on the human microbiome, as it is called, has been so intriguing that Jon has made it the theme of his latest popular science book I, Superorganism : Learning to Love Your Inner Ecosystem . The book draws on a vast body of scientific literature on cell biology and immunology and puts it across in a manner that is accessible to a broad audience. Jon was in the capital city earlier this week where he gave a public lecture on this topic at the University of Kerala Senate Chamber.
Studies on the human microbiome, though mostly in its fledgling phase, have already thrown up some never-before-known insights, forcing doctors and scientists to rethink the functioning of the human body. An example is of the immune system. “The bacteria inside us are constantly in a molecular chatter with all the major control systems of the body, including the immune system,” says Jon. Evidence seems to suggest that this chatter has made the immune system more robust in terms of its ability to put up a fight against pathogens. “Which is why, rather than over reacting and waging an all out war against all microbes, the body’s immune system seems to prefer diplomatic negotiations with them,” he adds. In other words, not all germs are wicked agents of diseases. In fact, it would only serve us better to keep those helpful bacteria inside us, as they make us far less vulnerable to diseases. This new scientific revelation has ushered in a paradigm shift in immunology.
Like everything else, the greatest risk to this microbial ecosystem seems to be our modern life style. “The three big things that matter are probably diet, the advent of caesarean delivery, which robs the baby of its very first inoculation of microbes from the mother, and may affect the early microbial community in ways we’re still investigating, and antibiotics,” explains Jon. It is too early to tell what the long term consequences of all this is going to be. But in some cases, such as in the use of antibiotics, the outcome is better understood.
Though antibiotics are fast acting, Jon feels that we should probably reach for them less often, especially for sickness in children and the elderly. Broad spectrum antibiotics can have devastating effects on the gut microbiome. The microbes may repopulate after an antibiotics dose; but may remain somewhat less diverse, which is equivalent to weakening the immune system.
So what is the right way to preserve this microbial zoo, and keep it the way our body needs? Do we have any control over it? The answer is ‘yes’, and the prescription pretty simple, says Jon. “Eat a varied diet; avoid processed food; lean toward vegetables and fruits that are high in fibre which microbes help to digest. And, ensure you have some fermented foods in your daily diet, so that as well as feeding your microbes you are also consuming some!”
Lecture series
Jonathan Turney’s visit to Thiruvananthapuram was part of ‘Science and Beyond', a joint lecture series of The British Council and the Indian Institute of Science Education and Research (IISER, Pune). In the coming months, the series plans to bring eminent writers, scholars and historians of science from the United Kingdom to India to make science more accessible through talks and workshops. For full schedule visit: https://www.britishcouncil.in/events/science-and-beyond
