Giulia Enders’s Gut delves deep into our tummy troubles

Got tummy troubles? Feeling depressed? Microbiologist Giulia Enders wants to get to the bottom of our problems.

Hand on belly isolated on white

What is one to call the stuff that comes out of our body and falls into the toilet? It’s a perpetual problem, one a doctor faces many times each day. On a ward round last year one of my registrars bent over an elderly patient just back in his bed after visiting the bathroom and sweetly asked him, “Did you do number ones or number twos?” He looked at her askance and grumpily boomed, “What is this? Kindergarten?” I could barely stop myself from cheering.

But what should one say? We have stool, poo, shit, crap, faeces or (my personal favourite, used by a 91-year-old patient of mine) “one’s duties”. Giulia Enders’s international bestseller Gut is all about whatever-you-want-to-call-it: what’s in it and what it means; how it’s made and how to make it even better.

The gastrointestinal tract is today’s organ du jour: the slimy, writhing focus of our quest for health, or ultra-health. According to Enders, obesity, high cholesterol, chronic fatigue, arthritis and all manner of psychopathology could be caused by something going awry in our guts; or more specifically, something going awry with the teeming colonies of bacteria that live there.

Enders, a German research microbiologist, obviously adores her subject matter. The book, in this English translation by David Shaw, is written in a friendly, enthusiastic voice, bolstered by hundreds of exclamation marks and cute cartoons. Enders’s project is to show how those essential functions of the human body that some people may consider unseemly or unspeakable are in fact wondrous and worthy of exultation. “Every time we go to the loo, it’s a masterly performance … burping or breaking wind might sound a bit gross, but the movements involved are as delicate and complex as those of a ballerina.”

Enders turns the events that unfold in our body every time we eat into a dramatic allegory. Body parts, plants and bacteria are given agency: “What plants really want is to reproduce — and then along we come, and eat their children. Instead of creating an emotional scene, plants respond by making their seeds slightly poisonous.” Or, “When we take a sneaky bite of cake, we never hear the roar of excited bacteria in our gut as they gleefully shout, ‘HERE COMES CA-A-A-KE!’ ” A pair of dysfunctional sphincters can be taught to “get to know each other again”. I found this narrative technique alternately endearing and irritating: is her aim to inspire our enthusiasm or tell a story for children?

Gut clearly and simply explains allergies, food intolerances, constipation, diarrhoea, reflux and vomiting. It also contains much trivia: that mice can’t vomit, that petrels vomit on purpose. She informs us that if we stick our finger up our nose we’ll find our nostrils don’t end there. She advises us to squat to defecate, leave our tonsils in until we’re at least seven, deliver our babies vaginally and breastfeed them. Read this book and you will understand why you feel terrible after an alcohol binge, sluggish after a heavy meal and become sick when stressed.

But somewhere along the way, Enders’s project of elucidating our inner workings morphs into a claim that the gut might be the control centre of our entire subjectivity. That abdominal pain and nausea cause feelings of unease will come as no surprise to anyone, but Enders pushes this cause and effect between what’s in the gut and one’s emotional state much further.

Depression, she claims, may be caused not by an “unhappy brain” or life circumstances, but by an “unhappy gut”. She cites small rodent studies to hypothesise that the kind of bacteria we have in our intestine may even determine our personality traits and our actions: making us gregarious or timid, for instance. Infection with the Toxoplasma gondii parasite may cause a person to engage in risky or self-harming behaviour, or even to develop schizophrenia.

To say that these claims are reductionist and fanciful is an understatement. However, it is understandable that when someone is completely immersed in the study of one thing — as Enders is with the intestinal microbiome — it can become the centre of their universe, and seem the origin and cause of all things. There is a single tempering sentence in the book, cautioning that “this excitement about gut research could still fizzle and come to nothing”.

The final section of the book covers pathogens (bad bacteria) and antibiotics, and the detrimental effect of both on the good bacteria in our gut. Enders summarises the benefits of prebiotics and probiotics on promoting or regenerating this good bacteria.

She ends on a completely sound and uncontroversial note: good bacteria generate or unleash vitamins, help us absorb our food and protect us from illness. “We should feed them well so they can populate as much of our large intestine as possible. Pasta and bread made of white flour on factory production lines are not enough. We need to include real roughage, made of real dietary fibre in vegetables and fruit … Our bacteria will like it, and they will thank us with their good services.”

I don’t buy Enders’s I-have-bugs-therefore-I-am story, her wild extrapolations from rat to human, nor her thinking, feeling, free-willed bacteria, but if this book convinces the population to eat more vegetables, she can use as many exclamation marks as she likes.

Karen Hitchcock is a doctor and writer.

Gut: The Inside Story of Our Body’s Most Under-Rated Organ

By Giulia Enders

Translated by David Shaw

Scribe, 272pp, $29.99