THE REALITY OF RUMBLEDOM
Rumbledom is a magical place where Borborygmus lives and works but, like everything else in his world, it’s not that far from reality. Although Borby’s message is simple, there is a fascinating, complex and evolving science underpinning it. Our initial aim was to introduce children to the concept of good nutrition in a way that was entertaining, personal and easy to understand. As we became aware of gut microbes and how they affect our health, we created Rumbledom, a fun place where we could explore more of what is happening within our bodies.


THE MAGIC OF THE GUT
Most people will be aware of recent scientific developments in what is known as the human microbiome. The gut is home to 100 trillion microbes, the majority of which, thanks to our immune system, are beneficial to our health. Our microbes have variously been described by scientists as superheroes, puppet masters, worker bees, tiny factories, a zoo, a jungle, gut flora and a coral reef growing on the rugged seabed that is your intestine. In Borby’s Rumbledom, these microbes are represented by both ‘funky fungus in the garden’ and the ‘Good Bugs’.
WHAT’S IN A NAME?
Borborygmus is the medical term for a tummy rumble. Ask any doctor. It was coined by the Ancient Greeks, supposedly because the word sounded like the rumble itself. Most people love the word. It rolls off the tongue. We created the shorter version, Borby, for young children. Interestingly, they almost always use the longer name. Perhaps that’s not surprising since kids love unusual-sounding names and learn them quickly.

MICROBIAL GARDEN & GUT FLORA
How many different plants have you eaten this week? If it’s just a handful, the range of your gut flora species could be quite limited, and your health too. The more diverse your intake of plants and the wider the range of flora, the better your health and weight. If we want a beautiful microbiome, we need to eat a rainbow of colours and a wide spectrum of varieties.
Jeannette Hyde (The Gut Makeover)
‘It’s useful to think of your microbial community as your own garden that you are responsible for. We need to make sure the soil (your intestines) that the plants (your microbes) grow in is healthy, containing plenty of nutrients: and to stop weeds or poisonous plants (toxic or disease microbes) taking over we need to cultivate the widest variety of different plants and seeds as possible. … Diversity is the key.’
Tim Spector (The Diet Myth)
‘So rather than focusing on what you should be eating to lose weight, or to lower your cholesterol, or to avoid diabetes, you should really be asking yourself what you should be eating to grow a good gut garden, because disease is rare when gut bacteria are balanced, bountiful and diverse.’
Robynne Chuktan
(The Microbiome Solution)
‘Containing our multitudes is not unlike a bit of agriculture. We use fences and barriers to mark the boundaries of our gardens. We use fertiliser to feed the plants. We uproot and poison incipient weeds. And we set the garden in a place with the right temperature, soil, and levels of sunlight to nourish whatever we want to grow. Animals use equivalents of all these measures to set the terms and conditions for their microbial partnerships. … every body part on every species has its own zoological terroir – its unique combination of temperature, acidity, oxygen levels and other factors that dictate what type of microbes can grow there.’
Ed Yong (I Contain Multitudes)
WHO ARE ‘THE GOOD BUGS’?
Borby’s Good Bugs are inspired by the behaviours of our microbes (including having Latin-sounding names – although those are also there just because they’re fun!) The descriptions of the Good Bugs mimic what’s going on in your gut, allowing for some poetic licence, of course. Informing children (and their parents) of the crucial role their Good Bugs play will help them make the right dietary choices.
‘We’ve evolved over millions of years to host an incredible army of worker bee microbes that are gainfully employed assisting in all of our bodily functions. They produce substances our bodies require but can’t make. They fight most of our battles for us. They even turn our genes on and off, activating those we need and dismantling those we don’t. In exchange, we provide room and board.’
Robynne Chutkan (The Microbiome Solution)
CHEWUS POOHUS
AKA CHEWY BUG
Chews up vegetables and poohs out helpful chemicals, like butyrate, that sustain the cells lining our gut and reduce the inflammation that causes so many modern illnesses.

LICKUS FLICKUS
AKA LICKY BUG
We eat many foods such as leeks and onions that we cannot fully digest without the help of microbes. We call these foods ‘prebiotics’. As a by-product of Licky Bug breaking down these prebiotics, she produces beneficial substances such as vitamins and healthy fatty acids.

HAPPUS CLAPPUS
AKA HAPPY BUG
Secretes ‘happy juice’ or serotonin, 95% of which is produced in the colon.

We now know that when bacteria break down fibre, they produce chemicals called short-chain fatty acids (SCFAs); these trigger an influx of anti-inflammatory cells that bring a boiling immune system back down to a calm simmer. Without fibre, we dial our immunostats to higher settings, predisposing us to inflammatory disease. To make matters worse, when fibre is absent, our starving bacteria react by devouring whatever else they can find – including the mucus layer that covers the gut.
Ed Yong (I Contain Multitudes)
Beneficial bacteria help produce and assist in the uptake of essential nutrients and other substances from the food we eat. … These bacteria use a surprising repertoire of enzymes to ferment and essentially ‘eat’ certain types of soluble dietary fibre that we cannot digest. …The most crucial element of this process is the production of short-chain fatty acids (SCFAs), the three main ones being butyrate, acetate and propionate. Short-chain fatty acids are the primary energy source for intestinal cells in the colon and have been shown to have many beneficial effects. For example, butyrate is the colon cells’ main energy source and has shown promise in helping to manage various gastrointestinal diseases, including ulcerative colitis and Crohn’s disease.
Eve Kalinik (Be Good to your Gut)
Serotonin, one of the molecules of emotion, is the signal for a “happy mood” in the brain. However, more serotonin receptors are found in the gut than in the brain. In fact, 95 percent of serotonin found in the body is produced by the gut’s nervous system. Being in charge of producing so much of this “happy chemical”, along with about thirty other neurotransmitters, it’s no wonder the gut is central to feeling happy.
Vincent Pedre (Happy Gut)
The particular set of microbes we harbour determines our ability to extract energy from our food. After the small intestine has digested and absorbed as much as it can from what we’ve eaten, the leftovers move into the large intestine, where most of our microbes live. Here they function like factory workers, each breaking down its own preferred molecules and absorbing what it can. The rest is left in a simple enough form for us to absorb through the lining of the large intestine. One strain of bacteria might have the genes needed to break down the amino acids that come from meat. Another strain might be best suited to breaking down the long-chain carbohydrate molecules that come from green vegetables. And a third could be most efficient at collecting up the sugar molecules that were not absorbed in the small intestine. The diet each of us eats affects which strains we harbour. So, for example, a vegetarian might not have many individuals of the amino-acid strain, as they cannot proliferate without a steady supply of meat. … what we can extract from our food depends on what our microbial factory has been set up to expect. … A regular meat-eater would have a sizeable collection of suitable microbes and would extract more calories from the hog roast than a vegetarian. And so it follows for other nutrients. … Someone who eats a daily teatime treat, however, would have a large population of fat-munching bacteria, just waiting to strip their next doughnut to its bare essentials, providing our snacker with the full dose of calories.
Alanna Collen (10% Human)
BASHUS SMASHUS & CHOMPUS STOMPUS
AKA BASHY BUG & CHOMPY BUG
They protect your immune system against pathogens – The Harmies – and muscle out
unwanted bacteria that have colonised the gut courtesy of an unhealthy diet.

There are several ways by which this microbe-immune system-brain dialogue can take place … One means of communication involves specialized immune cells known as dendritic cells, located just under the inner lining of the gut. Dendritic cells have “tentacles” that extend into the gut’s interior, where they can communicate directly with the group of gut microbes that live near the gut wall. These immune sensors are a first line of detection. Under normal conditions, receptors on these cell parts … recognise various signals from benign microbes, assuring the immune system that all is well and that no defensive response is necessary. Our immune cells have learned to correctly interpret these peace signals from interactions with a large variety of gut microbes early in life. In contrast, when harmful or potentially dangerous bacteria are detected through these mechanisms, they trigger an innate immune response – a cascade of inflammatory reactions in the gut wall – to keep the pathogens in check.
Emeran Mayer (The Mind-Gut Connection)
Microbes … influence the creation of entire classes of immune cells, and the development of organs that make and store those cells. They are especially important early in life, when the immunity machine is first constructed and tunes itself to the big bad world. And once the machine is chugging away, microbes continue to calibrate its reactions to threats.
Ed Yong (I Contain Multitudes)
BLUEBERRY BUBBLES
& THE BLUBE TUBE
Borby sends ‘blueberry think bubbles’ up the Blube Tube to the brain, keeping it informed of what’s happening in the gut. The Blube Tube represents our Vagus Nerve which, as Giulia Enders explains, ‘is the fastest and the most important route from the gut to the brain’. Colonise your gut with the right microbes and messages will largely be beneficial. On the other hand, Borby has to be on the lookout for Sugar Monsters and Fast Ones sending messages of their own, telling the brain instead to eat sugary snacks or junk food.

‘…So this nerve works something like a telephone connection to the switchboard at a company’s headquarters, transferring messages from staff out in the field. The brain needs this information to form a picture of how the body is doing. This is because the brain is more heavily insulated and protected than any other organ in the body. … The gut by contrast, is right in the thick of it. It knows all the molecules in the last meal we ate, inquisitively intercepts hormones as they swim around in the blood, enquires of immune cells what kind of day they’re having, and listens attentively to the hum of the bacteria in the gut. It is able to tell the brain things about us it would never otherwise have had an inkling of.’
Giulia Enders (Gut)
‘The special thing about the Vagus Nerve, though, is that it informs the brain about what we call ‘gut feelings’. Butterflies in the stomach, knowing ‘in your gut’ that something is wrong and bowel-loosening nervousness really do begin in the gut – the brain simply gets informed of them by electrical impulses shooting up the vagus nerve. … One idea is that by influencing our mood, our microbiota can control our behaviour such that it benefits them. Imagine, for example, one strain of bacterium that feeds on a particular compound found in our food. If we eat that food, thus feeding these bacteria, and they are able to reward us with a dose of happiness through the chemicals they produce, so much the better for them.’
Alanna Collen (10% Human)
AS FOR THE SNEAKY MESSAGES THAT SUGAR MONSTERS & FAST ONES MIGHT SEND …

‘Life in your gut is not for the faint-hearted. It is a state of endless war. Life down there is nasty, brutish and short. The microbes are not only competing for space and scarce resources; they also have different dietary demands. Some thrive on sugar, others love fat. The more sugar you feed the sugar eaters, the more they want. They are not like a friendly dog, hanging around waiting gratefully for whatever comes their way. They are fighting for life. They will do anything to give themselves the edge.’
Dr Michael Mosley (The Clever Guts Diet)
‘If you reach for a burger or a chocolate bar, what exactly is pushing that hand forward? … Different microbes fare better on certain diets. Some are peerless at digesting plant fibres. Others thrive on fats. When you choose your meals, you are choosing which bacteria get fed, and which get an advantage over their peers. … If they released dopamine, a chemical involved in feelings of pleasure and reward when you ate the ‘right’ things, could they potentially train you to choose certain foods over others? Do they get a say in your menu picks?’
Ed Yong (I Contain Multitudes)
“Each species of microbe has a preference for certain food sources that allow them to feed and reproduce. They have their own evolutionary desire to maintain their ecological niche and will do anything to ensure their survival. This includes sending signals to the hosting human that they want more of the same junk food that they thrive on.”
Tim Spector (The Diet Myth)
‘There is evidence that people who crave chocolate have different microbes in their gut and different chocolate metabolites in their urine. It seems clear that your profile of gut microbes, your desire for certain foods, and the metabolites that you produce from that food all align. … Since the microbial by-products can drive our contrasting feelings of pleasure, euphoria, depression, anxiety, discomfort, and pain, that is the place to look. The take-home message from this area of work is that by changing your microbes, you have a better chance to change your eating behaviour. The various bacteria in your gut are not simply innocent bystanders hoping you might accidentally choose to feed them over other microbes. They know how to biochemically influence you to choose their preferred food over others. A battle of signals rages inside you that eventually translates into a menu you only think you created.’
Rodney Dietert (The Human Superorganism)
BIBLIOGRAPHY
10% Human, Alanna Collen, 2015
Gut, Giulia Enders, 2015
The Gut Makeover, Jeannette Hyde, 2015
The Diet Myth, Tim Spector, 2015
The Microbiome Solution, Robynne Chuktan, 2105
Happy Gut, Vincent Pedre, 2015
I Contain Multitudes, Ed Yong, 2016
The Mind-Gut Connection, Emeran Mayer, 2016
The Human Superorganism, Rodney Dietert 2106
The Clever Guts Diet, Michael Mosley, 2017
Be Good to your Gut, Eve Kalinik, 2017
CONTACT
For further information on Borborygmus and Rumbledom, please contact david@borborygmus.co.uk.
Rumbledom, Borborygmus and Borby are registered trademarks of Rumblings Ltd.


