We are sterile in the womb and acquire our initial microbiome through birth and breastfeeding.
The microbiome changes dramatically until age 3-5, stabilizes in adulthood, and becomes more vulnerable after 70.
Transcript:
James Kinross
So it is a literal black hole. And where do all these gut microbes come from? As far as we know, and this is kind of controversial, when you're in utero, when you're gestating in the womb of your mother, you're sterile. And then as you're born and you're delivered into the world, you come into contact with your first group of microbes through the birth canal and then through breastfeeding, the things That you touch, and slowly your gut and your skin and your lung is colonized. And it changes with us at key moments in our development and in our aging process. And that has very, very important implications for our health. So your maternal microbiome, or the maternal microbiome, I should say, has a very important role in defining the health of the gestating infant. Then the second phase is from the minute you're born, because the microbiome then changes very dramatically until about the age of three to five, because it's so vulnerable to nutrition, Dietary, drug, environmental changes. And it also, therefore, has a very important role in helping our organs grow and our organs develop, most importantly, the brain. It then stabilizes. There's an argument as to what happens around puberty. It probably goes through another subtle change around the time of puberty. But then in adulthood, it's pretty robust and very stable, actually. It takes quite a lot to really change it until the age of around 70-ish. (Time 0:06:03)
Individual Microbiome Variation
While we share a common core microbiome for gut function, individual variation is substantial.
We only share about 10% of the same microbial strains, impacting disease experience and future therapies.
Transcript:
Ian Sample
Change, slightly more fragile. And you see changes at kind of broad levels in the microbiome. And are people's microbiomes completely different or are there sort of common microbes that we all have, you know, strains of bacteria that dominate, if you like? So there is a sort of, if you like, a common genetic microbiome that we share that allow our guts to function healthily, but individual variance is massive.
James Kinross
So at a strain level, you and I probably only share about 10% of the same strains of microbes in our gut. And that's very, very important for a couple of key reasons. (Time 0:07:20)
Microbiome Influencers
Diet, antibiotics, and other drugs significantly affect our microbiome.
High antibiotic use, particularly in developing nations, creates an 'internal climate crisis' by reducing microbiome diversity.
Transcript:
James Kinross
There external factors we know affect our gut microbes? So the answer is yes. Diet and nutrition in early life is the most important because that sets, if you like, the ecosystem for the rest of your life. And we know that breastfed infants have a different microbiome to those that are formula fed. Clearly, a kind of globalized, ultra-processed diet has an impact on it. But probably, well, in my view, what is pharma important is our addiction to antibiotics and also our addiction to pharma and to drugs. So antibiotic consumption, it's clearly a double-edged sword. I couldn't do my job as a surgeon without them. And they're a very precious and important drug. But they have absolutely transformed not just the human microbiome, but the planetary microbiome, the global microbiome. And we consume just vast quantities of them. And the majority of antibiotic consumption is actually happening in low and middle income countries. It's happening in economies that are rapidly or have rapidly grown. So China and India, for example. We take about 4 trillion doses of medication per year globally, which means that everywhere in the world, every day, about half the globe's population is taking a drug or a medicine. And many medicines that we don't typically think about as antibiotics actually have an antibiotic effect. All right. So about a quarter of them in one study. And collectively, these things are a very short period of time have had a very dramatic impact on our microbiome. And because our microbiome is passed to us through our parents and it has a generational shift, that is, if you like, eroding our microbiome. If we take the hypothesis that our health is determined by the biodiversity of these microbial ecosystems at critical moments in our life, and that that biodiversity is being lost Or certainly changing, then it's an internal climate crisis. And because our microbiome links us to the global environment, I mean, literally through the microbes that transition through us, we're of course connected to the broader global Climate (Time 0:08:20)
Diet and Bowel Cancer Risk
James Kinross's research compared Western and rural African diets and their impact on gut health.
Rural Africans have a lower risk of bowel cancer and other diseases due to high-fiber diets.
Transcript:
Ian Sample
So how does diet determine our microbiome? And then how does that impact our health?
James Kinross
First of all, you know, 80% of the world's antibiotics are made in food production. So the production of food and the manufacture of food is changing our microbiome through that process. And of course, not all food is sterile, right? So you can track things like sushi consumption with the rise in pinworm infections in the gut. But generally, you have to think about your bugs as being pretty similar to you, right? Which means they're sat in your gut, pretty hungry, waiting for the next meal to come through. And they can only respond and react to the nutritional or dietary stress that you put them under. Now, what we've done in our studies is that we have compared like a Western diet to an Africanized diet. So I'm a colorectal surgeon. I'm interested in bowel cancer. And if you are a rural South African, so if you live literally a rural life, your risk of bowel cancer is dramatically lower than someone living in the West. You don't get inflammatory bowel disease. You don't get diverticulosis. You don't get allergies. You don't get asthma. You get lots of other diseases of deprivation and they have high rates of infection. I'm not saying that they have a perfect life by any stretch, but the disease is very, very different. And rural Africans eat a lot of fiber, tons of it, up to 50 grams a day. The average Londoner probably has about 10 to 15 grams. So if you were to have an African's diet, you'd blow up like a Zeppelin. You'd be pretty unhappy and you'd fart a lot and your colleagues would hate you. So what we did was we crossed over those diets between African-American men who have very high rates of bowel cancer and rural South Africans who have very low rates and have these very, Very different diets. And when we did that, what we found was actually the microbiome doesn't change very much. If you're an African, you moan a lot about a high-fat, high-protein diet, but actually microbiome doesn't change. But the function of these microbes changes dramatically. So they start pouring out bile acids, short-chain fatty acid metabolism dramatically changes. And the consequences of that are inflammation. So you can think about your microbiome like an engine. It's going to respond differently to the type of fuel that you put in it and the efficiency of that engine is going to have a very very big impact on the health of your car. (Time 0:10:33)
Fecal Transplantation Success
Ray, a retired bus driver, suffered from Clostridium difficile after antibiotic treatment.
A fecal microbiota transplantation successfully treated Ray by resetting his gut ecosystem.
Transcript:
Ian Sample
James, this growing knowledge of the gut microbiome is also changing how we practice medicine. In your book, you give an example of a retired London bus driver called Ray, who had been really unwell. He had been in hospital and was treated with antibiotics. He was discharged. And then as a result of all of that, Ray found himself with yet another very dangerous illness. Tell me about that. Well, I mean, first of all, thank you to Ray and to his family. Ray sadly passed away, actually.
James Kinross
So Ray was interesting because he had what you might call a superbug. He had a bug called Clostridium difficile, was what we used to call it. And he was very, very sick with it. And Ray had failed treatment with antibiotic therapy. And he was given something called a fecal microbiota transplantation. And that was because he was so unwell, he was probably going to die if we didn't change tack very quickly, that the only solution was to completely reset his gut's ecosystem. And the only way that we can really do that at the moment effectively is through this process of faecal microbiota transplantation, which is as gross as it sounds. It's a poo transplant. It's a poo transplant, yeah. And so what happened? He was enrolled into a trial and what happened is that a donor was found and that donor was screened and mapped and a fecal sample was provided. And then that was prepared. And when we prepare it, we screen out pathogens and bad bugs that we really don't want to give that we know are bad. And I think it is important to say that because this is not something you should be doing at home. And then that was put into, if you like, a fecal milkshake. We mix it with a bit of saline, so it's a liquid form. And then we place a tube in the nose, down into the stomach, and then we pass that fluid down the tube. What that microbiome transplant then does is it then, if you like, creates a more diverse ecosystem. It resets the ecosystem, and it creates competition for this superbug, which can no longer survive. But it also changes the way that the gut works. And we think actually that is one of the important mechanisms through which the faecal transplantation is able to kill Clostridium difficile. And in Ray's case, it was transformative. This man was incredibly frail. He was really very, very sick. And he was able to leave hospital just a few days later absolutely well. That's quite amazing that it had such a transformative (Time 0:14:59)
Improving Gut Health
Avoid unnecessary antibiotics and polypharmacy, and get vaccinated to protect your microbiome.
Increase fiber intake by 7 grams daily to reduce stroke risk.
Transcript:
Ian Sample
Through which we shared microbes. So kissing is good. You should do that for your microbiome. James, beyond kissing more, what's your advice to people for developing and maintaining a healthy gut microbiome? Number one is don't take antibiotics unless you really, really need them.
James Kinross
I'm not saying don't take antibiotics. I'm not an anti-antibioticist. But they are just a precious resource anyway in terms of antimicrobial resistance, and you shouldn't be abusing them anyway. But if you're going to take an antibiotic, ask your doctor, am I taking the right one for the right reason? Is this as targeted as it can be? And ask them to prove that really is a microbial infection that's driving it. Again, try and reduce your reliance on polypharmacy. So what that means is taking lots of medicine. So antacids would be a very, very good example of that. Are you really doing everything that you can to try and reduce those things and their impact on your life? If you can minimize those unnecessary medicines in your life, your microbiome will be infinitely happier. Number two, get vaccinated. Because if you're vaccinated, you're much less likely to need antibiotics, right? Number three, obviously what you eat is very important. Delete your food delivery app and eat socially, right? So your food, if you're sharing it with people, you're sharing your microbiome. And it's also good for your mental health. It's good for everything, right? So share your food. Don't eat powder that comes out of a packet and think your gut is healthy. It just isn't. It's just terrible. Don't do it. Like your food needs a food matrix. It needs substance because that's what microbes need, right? To properly absorb it and just avoid anything that's prepackaged and ultra-processed. That's really, your microbiome just does not like that, and it's really not good for you. And if you take one thing away from this podcast, take this, which is that if you just put 7 grams more fiber in your diet per day, your risk of stroke will fall. And the more you put, the lower your stroke risk will come. Part of that is because fiber is just a good thing. But part of it is because bugs are responsible for many of the anti-inflammatory properties of fibre, such as stroke prevention. (Time 0:20:20)
