We tend to think that illness is caused by something. Chemicals trigger cancer. Viruses create colds. Poor diets give us heart disease. But what if much of what ails us in the 21st century isn't caused by a presence but an absence. That's the idea behind a recent book that takes wellness in a whole new direction.
An Epidemic of Absence, by Moises Valasquez-Manoff, looks at the theory known as the Hygiene Hypothesis. I've discussed this idea before, and it's not without its controversies. Trying to convince people that arch nemeses like bacteria, viruses, fungi, and worms keep us healthy is a tough sell. But I suspect that if everyone read this book, it'd get a whole lot easier.
Velasquez-Manoff weaves hundreds of threads together to make a convincing argument that while medical advances like vaccines and antibiotics have erased much human suffering, they've also erased the vast communities of microbes and other organisms that once inhabited our gut, our skin, and nearly every place in between. And that means trouble because these may not have been enemies but ancient evolutionary friends whose presence keeps our immune systems primed and allergies, asthma, inflammation, bowel disease, cancer and maybe even things like autism and multiple sclerosis away.
It's a fascinating if heretical notion. Is our hyperbolic obsession with cleanliness as evidenced by the insatiable demand for antibiotics and antibacterial products, really killing us? The wealth of evidence Valasquez-Manoff collects here strongly suggests that it is.
It starts with this: Healthy people carry 100 trillion bacteria on and inside themselves. For every one human cell in your body, there are 10 bacteria cells. We are and have always been walking Petri dishes. But since the mid-1800s, better sanitary and medical arts have increasingly sterilized life and removed from our tissues not only the 150 or so bacteria that can threaten our health but thousands of other species as well.
At the same time, cases of immune disorders, allergies, inflammatory diseases and other conditions have mysteriously skyrocketed. It's more than a little odd and here's something odder: The cleaner and more modern the country, the higher the rates of these illnesses. The "dirtiest" among us, those who live in close proximity to soil, animals, and each other, like farmers and tribal peoples, suffer much less if at all from such things.
Clearly something's going on, and this book and all the scientists whose work has contributed to it appear to have found it, because when you add up everything we know, as Velasquez-Manoff does, you end up with a compelling case that the biggest victims in humanity's ongoing war against pathogens are ourselves.
This makes this a book for every nightstand, and the good news is that it's delightfully readable. There's a bit of a detective story quality to it as Valasquez-Manoff breezily explores an attention-getting series of fascinating who-done-its. More importantly, the ideas here are likely the first wave of a coming medical revolution. What you'll learn may help someone you know.
In the end, the message is simple: we ourselves are ecosystems, and just as in nature, these environments within rely on a delicate balance we've unknowingly thrown off. It's time to respect the worlds inside us and the creatures that inhabit them. As we've learned, to cut one strand in the web of life is to cut many. This book shows us those strands exist inside our own bodies as well and tells us it's time to reconnect them.