Why the science world is getting *so* excited about post-biotics (short explainer)

0:00This show is sponsored by Primidine, a clean, natural and science-based spermidine supplement that's been a long-time staple in my own longevity stack. Because studies suggest that through autophagy, spermidine increases healthspan and upregulates a range of health markers, from memory and cognitive function to heart health, hormone balance, fertility, and even hair growth. Plus, you can be assured that all ingredients undergo rigorous third-party testing. Buy Primadine now at OxfordHealthSpam.com and use the discount code DrSophie, that's D-R-Sophie for 20 % off. This show is sponsored by Microbes, an award-winning liquid probiotic that's now a staple for me because Microbes, with a Z on the end, is different.

0:47For one thing, they source directly from the soil on their Wiltshire farm, meaning more diversity with at least 15 strains of good bacteria in every single shot. It's brewed so it can survive in the stomach and a remarkable 92 % of customers say it makes a difference. Plus they offer micro-friendly cleaning, gardening and even microbes for dogs. Buy now at microbes.co.uk and use the discount code sophie20 for 20 % off. Hi I'm Sophie and this is Age Well with Dr Sophie Schotter, a space devoted to all things health, wellness and longevity. Because for me, aging well is about looking and feeling like the best possible version of ourselves inside as well as out.

1:31So together with my producer Fee, I'll be deep diving into the latest research sifting fact from fiction. I'll also be talking to all kinds of trusted experts tapping into their knowledge, along with bringing you conversations from a range of interesting women and men finding out how they age well. So this is my show. Welcome along. And as always, thank you so much for listening.

2:00Dr Sophie Shotter:So Sophie, there's so much conversation around gut health, but I thought it might be useful to recap the very latest essential facts on gut health, as this is one of the things that you're really good at and one of the things this podcast is becoming known for? I think it's a great idea because very often we use these phrases and terms without being 100 % sure of what it is we're talking about. So firstly, the term gut generally refers to the gastrointestinal tract, sometimes also known as the digestive tract. And this includes the stomach and intestines. And the word gut is also used to refer to the gut's microbiome, which is this vast ecosystem of trillions of microorganisms, which might be bacteria, but could also be fungi, yeast, or viruses, including good viruses.

2:49And these all live in our digestive system and are essential for helping us digest certain foods and produce certain nutrients like vitamin B. In a healthy microbiome, the bulk of these microbes are either good or neutral. And this microbiome changes throughout our life. So our first microbes typically come from our mothers if there's been a vaginal birth, but also from breastfeeding. And we acquire more throughout our childhood, mostly from the foods we eat. Genetics play a role as well, and that kind of determines the microbes we might inherit. In adulthood, our gut microbiome tends to stabilise, but it can be disrupted and changed by things like diet for either the good or the bad, but also by stress, travel, antibiotics, and some prescription drugs, all of which can negatively impact the gut.

3:40The not so good microbes are usually kept in check by the good ones. But if the not so good ones take over, again through unhealthy lifestyle or diet, this is when we're prone to digestive issues or leaky gut or yeast infections or things like SIBO, which is small intestinal bacterial overgrowth. Plus, of course, good gut health is linked to better health outcomes across a range of areas from serious disease to mental health. And I'd like to point everyone towards our episode with Dr. Will Balsiewicz for more on this as a special expert partner episode because it's one of our biggest episodes and certainly a personal favourite of mine.

4:17And by the way, we also have communities of microbes on the skin, in the mouth, on the eyes, and for us as women also in the vagina.

4:24Dr Sophie Shotter:Yeah, and I'd second that on the Dr. Will Balsiewicz episode. It was, and it is a brilliant one. so let's move on into pre pro and postbiotics and i suddenly feel as though there's all this new stuff that i need to learn particularly with postbiotics can you break it all down for us as a sort of quick initial explainer no problem first let's do a quick 101 on the difference between probiotics and prebiotics because both are great for gut health but they do work in different ways Probiotics are actual live microorganisms, usually good bacteria, but sometimes yeasts and other things. And when they're eaten, they simply add to the population of good bacteria we already have.

5:07We can take them as a supplement or we can eat probiotic rich food. Things like natural yogurts, some cheeses and particularly fermented foods such as kefir, kraut, kimchi, kombucha. Essentially, probiotics are good bacterias, good yeasts, and the prebiotics are the food that helps them to grow. So prebiotics are not actually alive. They're these indigestible fibres, the parts of a plant or a legume that won't dissolve in water. So prebiotics act as food for those good gut bugs or good bacteria we have, and also for any probiotic foods we eat or probiotic supplements we take. Basically, prebiotics help these good bacteria and yeasts and other microorganisms to not just survive, but to thrive.

5:58And while the vast majority of prebiotics are fibres, the reverse isn't true. So by that, I mean that not all fibre is prebiotic. One very well-known prebiotic is inulin, which is a particular fibre, but there are others. I'd say that prebiotics are a relatively recent discovery and there's currently no specific daily recommended intake. But since the majority of us don't have enough dietary fibre, I'd start with fibre to increase your prebiotics. And another word to throw into the mix, symbiotics are a mixture of prebiotics and probiotics. So, for example, if you took a high-fibre prebiotic fruit, like an apple or a pear, and serve it with a probiotic food like a live natural yogurt, that's a homemade symbiotic.

6:48Dr Sophie Shotter:Okay, and then should we move on to postbiotics? Yeah, and this is where the science is getting quite excited. Our body produces postbiotics after digesting or metabolising prebiotic and probiotic foods. So postbiotic is this umbrella term that represents various waste products or byproducts. And these have already been metabolized and now sit fermented in the gut. So postbiotics are these waste products that are left behind. And waste sounds so dismissive, but these are anything but. And in fact, there's a lot of talk around them being the next big thing in nutritional science and that they may even have therapeutic uses.

7:31So definitely watch this space. That being said, the science of postbiotics is still quite new and these byproducts can be both beneficial and harmful. In terms of the beneficial postbiotics, to try and explain it, the breakdown of fiber creates this treasure trove of vitamins, enzymes, amino acids and short chain fatty acids. And these short chain fatty acids that people are really excited about include something called butyrate. and certainly listeners might recall Will Bulsiewicz talking to us about butyrate last summer. Butyrate is like this superpower molecule that we now know plays a pivotal role in various aspects of health.

8:11It's been linked to a reduced risk of various chronic diseases and we now think it can also potentially support brain health and that it may have powerful anti-inflammatory properties. And how do we increase butyrate? No prizes for guessing because we talk about it all the time on the podcast. It's fibre. This is all about plant-based foods and fermented foods.

8:33Dr Sophie Shotter:But you said that some postbiotics are not good for us. And again, the science here is new, but we do know, for example, that eating meat creates byproducts which eventually form something called trimethylamine N-oxide or TMAO. And elevated levels of this have been associated with an increased risk of clot-related cardiovascular events. We also know that staying on a high-protein, low-carb diet in the long term often means that people don't eat enough fibre, which again is linked to a higher risk of colon cancer. Another type of less positive postbiotic is bile acids, which are again produced when we eat too much high-fat food.

9:16And bile acids have been linked to inflammation and, once again, colon cancer. Interestingly, one clinical study showed colorectal cancer patients produced significantly lower levels of short-chain fatty acids in their gut than healthy participants. Another study found the numbers of bacteria that produce short-chain fatty acids were noticeably low in premenopausal breast cancer patients. But to keep things positive, the reverse is also true. So a review at Western Sydney University found short-chain fatty acids, particularly again butyrate, have shown promising results against breast and colon cancer.

9:53Some cellular and animal studies have also reported that butyrate can even help chemotherapy to work better against breast cancer and to help regulate the immune system. And there have been several epidemiological studies now conducted that have reported that a fiber-rich diet can lower the risk of colorectal cancer because fiber-rich diets lead to the production of, surprise surprise, short-chain fatty acids in the colon. It's the same message over and over again and fibre really is key and the short-chain fatty acids are absolutely essential.

10:27Dr Sophie Shotter:And when you mention that the science world is getting very excited about postbiotics therapeutically, can you expand on that? Yeah, but we don't have a lot of research here yet. There are a few really interesting examples of postbiotics potential for helping to ward off illness and disease. So as an example, one admittedly very small study involved scientists recruiting people with ulcerative colitis, which can be quite a nasty inflammatory condition of the gut. And researchers gave participants either a butyrate enema or a placebo for eight weeks. So for anyone who doesn't know, a placebo means something that doesn't have any biological action.

11:10And those receiving the butyrate had significant reduced markers of inflammation and improved symptoms. But for transparency, again, other studies haven't found such significant effects. There's also some evidence from animal studies that a postbiotic short-chain fatty acid called acetate might help to protect against E. coli. And staying on acetate, a mouse study found that increased acetate levels were linked to improve glucose sensitivity and reduced fat around organs. Other researchers have shown that short-chain fatty acids reduce appetite. So again, this could possibly help to treat obesity.

11:47Some scientists are investigating whether short-chain fatty acids might even help treat multiple sclerosis one day. There's one interesting study on a dead postbiotic called L-pentosis strain B240. And that's a bit of a mouthful. But what's interesting is that it showed improved resistance against infections such as the common cold, meaning these postbiotic good bacteria don't necessarily have to be alive to be helpful. Other scientists are investigating whether something called exopolysaccharides, produced by lactic acid bacteria, which is common in fermented food, might even help to treat cancer or reduce the risk of it.

12:27And similar studies are happening with something called lipotracoic acid. So as you can kind of hear, none of this is advanced human science yet, but it is potentially quite exciting and progressive research, just limited to labs or animals at the moment.

12:44Dr Sophie Shotter:And also in terms of diet, it seems that a lot of us, me included, have focused quite heavily on probiotics, but we've sort of ignored the prebiotics bit. Yes, you're definitely not alone there. I read about an interesting BBC study where they took two groups. half of them were put on a probiotic rich diet so foods containing good bacteria and the other half were put on a prebiotic rich diet and both groups had their poo tested daily to measure the change in bacteria and the prebiotic group managed to increase their good bacteria numbers by 133 million which as I said at the top of the episode given we've got trillions in our gut is actually quite a small change, but it's definitely encouraging.

13:28So meanwhile, the probiotic group saw very little change over the week. So what we do know in the long term is that a probiotic-rich diet can make a difference, even if that study in the short term didn't reflect that. Interesting. So what are the best prebiotic foods? so it's things like oats nuts and especially walnuts legumes artichokes chicory root garlic and onion leek asparagus all of these are really good prebiotic vegetables underwrecked bananas are apparently also a really good source and cocoa though you need to look for at least 70 dark chocolate ideally the vegetables mentioned here should be eaten raw which is so much easier said than done.

14:18But for the ideal diet, we should also include fermented foods like sauerkraut and kimchi, because these have both prebiotic fibre and the live probiotic bacteria, both of which help produce healthy postbiotics in the gut. So with pre, pro and post, it's not a case of focusing in on just one. All three of these work together.

14:41Dr Sophie Shotter:So looking at pre, pro and postbiotics, we now know that a plant-based fiber-rich diet is the diet we keep saying over and over again but with supplements what do we know i would actually say it doesn't have to be purely plant-based but very rich in plants so i will caveat it with that i'm not against eating animal protein in moderation from carefully selected sources so the whole concept of a mediterranean diet but the key here is a lot of plant and a lot of plant diversity. So let's start with probiotics and these are usually lab-grown bacteria that are similar to those in our guts. They should be live and active though there's a lot of controversy around some that are sold that are either inactive or that start off active but die before they can reach the gut because the acids in our stomach are so powerful.

15:37Most probiotics are in capsules, some need refrigeration and others are shelf stable. I will say that if you're taking probiotics for a specific purpose, the type you're taking matters because they're not all the same. They all have different functions in the body. We usually measure probiotics in what's called colony forming units or CFUs, which is the number of viable microbes per serving and this typically falls somewhere in the billions. But higher CFU counts are not necessarily better. The best probiotics are the ones with efficacy in scientific studies. So for example a brand like SimProof which has actually had scientific papers published in medical journals and this is a liquid.

16:19People often don't realise that the microbes in probiotics are transient meaning they pass through the body and don't typically form permanent colonies in the gut which is why taking them consistently is important because they don't stick around for long. In terms of brands, some of the probiotics I've seen recommended include brands such as Microbes with a Z on the end, BioCult, Optobac, especially its female blend, plus VSL hashtag 3. NutraVita 60 billion CFU, ProBioCultures Complex has had really good reviews. VidaGlo Gut Pro and Thorn's Sacro Bee also have two. And again, Simprove consistently reviews well and is one I have used.

17:03I could go on. But I have to say, I also really like Zoe's Daily 30, which, as Professor Sarah Berry told us, is a plant-based real food, next-gen type supplement. I also agree with scientists in that we all have individual probiotic needs based on the state of our gut health, which will vary really wildly from person to person. It's this ecosystem we talk about. So before supplementing, start with diet first. And if you then feel you need to supplement, and the best guide here is how your tummy feels after eating and what your poo is like and how often you're going, then do a reputable gut health test first and we can link into our at-home health tests episode for that.

17:44Dr Sophie Shotter:Yeah, mine was really interesting and I think yours was too because it was so specific in terms of the exact bacteria I had than the ones that I needed. So it was really, really useful. What about prebiotic supplements? So the first thing to say is that prebiotics occur naturally in many plant-based foods. So again, start with a plant-rich diet. And again, you shouldn't need to supplement. Also for people with certain gut disorders, prebiotic supplements can actually exacerbate symptoms. So do check in with your doctor. But if you feel the need for extra help, and certainly if like us in the last year you did a gut health test and it suggested extra help, you might want to try a supplement.

18:27There are a lot out there, so check the research and it's not a bad idea to check reviews too. The best prebiotic supplements depend on your individual needs, but ensure any prebiotic contains things like chicory roots, inulin or other prebiotic fibres. To name check just a few brands that seem to have efficacy you could try some from the new company so that's NUE Co or again Biocult, Biomuno is also well regarded. Having probiotic and prebiotic supplements can potentially be beneficial and science suggests that the prebiotics might help improve the viability of the probiotics so as they make their way through the guts that the prebiotics feed the microbes.

19:11But the same message is coming through from all the scientists. Focus on diet first. So back to probiotics and experts do tend to agree that probiotics should be taken with food rather than on an empty stomach as this helps reduce the amount of stomach acid that might destroy some of the live cultures. Most products today are developed to allow the probiotics to reach the intestines without being affected by that acid in your stomach but I'd always advise you to do your research. And what about postbiotic supplements? So while the concept of postbiotics is still quite new, postbiotic supplements are now on the rise.

19:50Butyrate supplements, for instance, are becoming increasingly common. But I'd say that a known deficiency in butyrate could signal an underlying issue with diet. So fix that rather than reach for a supplement. Because the most effective strategy for boosting postbiotics is basically embracing a diet that's rich in fermented foods and fibre. And as the team at Zoe tells us, research into postbiotics is still in its infancy. And if you see a postbiotic on the shelves, it's unlikely to be a miracle cure. And remember as well, supplements are not regulated. So whatever you take, do your research.

20:25Dr Sophie Shotter:Final question, is it worth taking probiotics after antibiotics? The jury is still out on this one. And one of the problems is that there aren't enough studies on any one particular probiotic to say this one works and this one doesn't. One concern is that while they're generally assumed to be safe there have been worrying cases of probiotics causing problems among more vulnerable patients such as fungus spreading into the bloodstream. Having said that a study by scientists at the Weizmann Institute of Science found that even among healthy people probiotics after antibiotics have actually hampered the recovery process.

21:02from what I've read the evidence is mounting that taking probiotics when gut health is already compromised may not be such a good idea though other experts say specific strains like clostridium butyricum I think is how you say it have been shown in trials to improve antibiotic associated GI symptoms when taken concurrently with the antibiotic the problem seems to be not so much taking probiotics but not understanding that all probiotics have different strains and we all have different gut ecosystems. So what works well for one person may have the opposite effect on someone else. In fact science is now suggesting that our probiotic intake needs to be personalized based on our own personal microbiome.

21:48So here we're back to gut health testing again and we'll link into that at home test episode because I think that was a really useful one and both Fi and I had really different results.

21:58Dr Sophie Shotter:Yeah okay any final thoughts? We focused a lot on diet in this episode but a healthy gut environment is also impacted by other things stress, alcohol, processed food, excess sugar, antibiotics and also other medications. A lack of sleep, a lack of exercise I could go on. So as always this is a reminder just to keep all of those pillars of good health going. brilliant thank you so much and all of the stuff and postbiotics is fascinating and as you say watch this space thank you so much sophie thank you fee and that ends this week's podcast if you want to find out more about me and my work or maybe book a consultation head to dr sophie shotter.com and you can find me on socials at dr sophie shotter and again thank you so much for listening Bye.