Anxiety, Gut Health and How to Improve Your Microbiome

0:02Welcome to The Wellness Scoop, your weekly dose of health and wellness inspiration. And as always, we're here as your hosts. I'm Ella Mills. And I'm Rhiannon Lambert. And today we have been overwhelmed with questions on gut health. So for today's episode, we have the most incredible Tim Spector, of course, is the professor of epidemiology at King's College London and the co-founder of Zoe. Exactly. We've got one of the world's most cited scientists here to unpack all of your questions, as always. And as Rhys said today, it is a deep dive on gut health from mental health to UPFs, emulsifies what he's got wrong in his career, there is a little bit of everything coming up for you.

0:43Well, Tim, welcome to the show. We're so thrilled to have you here. And essentially, Rhea and I were just inundated with questions from our community about their health, about wellness, about all the myths and trends. And we have had, as you can imagine, an influx of those questions focused on gut health, the microbiome, and all things that is your absolute area of expertise. So we thought what better to get you on the show and put some of these questions to you. Squeeze my brain and get something out. That's what we intend to do. That's what we're hoping, Tim. And our first question today is from Joanna from Portugal.

1:19So we're getting questions from all around the globe for you today. No pressure. We started with a good all-rounder. How do I have or know I've got good gut health? I know that the main indicator, she said, is our stool. Is that correct? So different levels of this. At the sort of optimum level, you get a gut microbiome test, which, for example, there are lots of companies around the world. Zoe offers it in the US and the UK. Generally cost between 150 and 250 pounds. That's the sort of gold standard. And then if you can't afford that, then the other thing is to look at your, just listen to your body, really, So am I constipated?

2:01Am I having intermittent constipation, diarrhea? Am I having bloating, gastric pains and upsets? And that really is a sign that you're likely to have poor gut health, as well as a whole range of mild common diseases. So if you've got a lot of food allergies, you're more likely to, if you're overweight, metabolically not particularly healthy, you're also likely to have poor gut health, anything that causes inflammation, so autoimmune diseases, allergies, et cetera. And even nowadays, mental health issues will be reflected in your gut as well as we'll probably get into. But if you're not going regularly to the toilet and you're not producing a soft stool, or it's always runny and you're going several times a day, then you've got some abnormality going on in your gut microbes.

2:55And in those tests, Tim, what is the main thing that you're looking at? We've actually just got a paper accepted in Nature changing the scores for the gut tests. So in the past, we used to look at what was called diversity, which is just the number of different species that you have, which was a crude indicator of health, but it lumped good and bad together. And so often vegans did rather badly because they might have had less bad microbes, but a meat eater would do better because they would have bad microbes which contributed to the diversity. So this new score, which is based, we've now got 300 ,000 people in our database, is pretty good.

3:39It now cuts across all types of food eating and countries, et cetera, and it compares good and bad bugs. So we've selected the 50 top bugs that are related to health and good diet, and the 50 bad bugs that are related to bad health outcomes and bad diets. And what we're seeing is the ratio of those two is the best overall indicator of health. And it also changes over time. So if you go on a good diet or you take high fiber supplements or probiotics, then you're to see some changes in that gut test, which wasn't the case with the old diversity score. You often got some disappointing results because it was slightly confusing.

4:26You might have one microbe that is really good and takes over and therefore squashes some of the other ones. So I think this is a real breakthrough and hopefully it's going to help the whole field move on and not have these negative trials that we had before often, which we couldn't really explain. So I think people will be doing this like a blood test now, getting an annual gut health checkup. And the price, as more people do it, will keep coming down. And Tim, you said you had 300 ,000 people in your database there, and you're looking at the different diets and the effect on the microbiome. Are there any kind of really obvious trends or indicators?

5:03Because I'm sure people are listening and thinking, well, what does that mean? What diet should I be following? What should I take from that? Yes. So we looked at dietary patterns and the one that came up top of all the ones we've looked at so far, what's called the healthy foods with a healthy plant diversity index, HPDI. It's a bit of a technical term. Essentially what that means is a healthy diet where you've got a rich diversity of plants. And that trumps everything else, better than low-fat diets or high-fat diets or worrying about proteins or anything else. And we combined that with another study where we compared vegans, vegetarians, and omnivores in about 20 ,000 people.

5:51So these are really big studies for once. So we're pretty sure what's going on. And we found that the average vegan had a healthier gut than the average vegetarian who had a healthier gut than the average omnivore, but the very top 5 % of all the best gut health people were often meat eaters who had a very small amount of meat and dairy, but had huge amounts of different plants. So if you combine those two sort of studies, then it's coming out that plant diversity is the number one factor, a healthy plant diversity. So real plants, not highly processed plants, but that's the overall finding, I think, that allows you to then eat that in a variety of different ways, depending on which part of the world you're in or what else you want to eat or what you don't want to eat.

6:48So that's something that's really come solidified in the last year or so it's really fascinating i was actually in a conference in france at denon and the uh was it the the person that discovered akamencia the um specific strain was speaking about the fact that we just don't know yet there are so many more to be discovered in the gut itself you know these amazing bacteria that are providing benefits and of course eating plants what you're saying is helping that bacteria to flourish and you know the good ones to do the job they need to do And we actually had a really good question come in, which I think is quite fascinating.

7:26People are a bit confused on what's more important about the gut microbiome. So is it the byproducts of the bacteria itself or the number overall? And you said at the beginning you used to classify, of course, all of them grouped together. So I'm assuming you're going to say it's discovering the new strains. It's a tough question, actually, that one, because in this new group of 100, important microbes to know about in your gut. Of the good ones, most of them don't even have a name, newly discovered. So we know very little about them at all. We have to start from here now. So what we knew in the past doesn't really transfer over to what the best ones to look at are now.

8:07They're just some examples. In general, I think we believe that microbes act through the chemicals they produce predominantly. There are exceptions. There are some predators that eat each other and things, and phages can eat some microbes, and that helps, and parasites and things. But in general, they're like little mini pharmacies producing lots of thousands of chemicals that interact with your immune system, either in a good way or a bad way. So that's the way, I think, to think about them. But we also know the lining of the microbe itself, even the dead microbe can have an effect on our immune system.

8:46And we know this from the latest work on probiotics, which shows that even dead microbes have a role. So I don't think it's all or nothing, but I would say, yeah, it's the chemicals they produce. And that's why the other thing we've done in our testing at Zoe is to combine the microbes into clusters, because we believe they They work in groups to sort of be anti-inflammatory, for example, which is calming down the immune system. And so you have a group of them in a cluster that you can follow now, or there's a group that are responsible for how you deal with fat, how you break down fat in your body and where it's deposited in your body are the ones that are controlling your blood sugar metabolism.

9:33And so we're trying to put the ones that are working together into these groups so that we're not obsessed with just one microbe, which some people might have and others not, because you've got to remember, we're all very different. We only share about a quarter of our gut microbes. So generally, we've got lots of unique ones. So if we can put them into these larger groups, it starts to make a bit more sense. And you can start, hopefully, what people would do is be tracking, say, their immune cluster of microbes over time, if they're worried about allergy or autoimmune disease or whatever it is.

10:08And I'll also be more interested in tracking the fat busting group of microbes and see how they're doing. So I think it's a great question. It's driven mainly by these chemicals, but there might be hundreds of different microbes that produce the same chemical. So although we're different, we're not so different that we can't produce these chemicals just because we don't have the identical microbes. That makes so much sense. And obviously we were talking about diet and what the effect of diet is. You've been so vocal in the conversation around ultra processed foods and their effect on us. Unsurprisingly, we've had a lot of questions on the link between UPFs and gut health.

10:47This question in particular came from Natalia, who said, I'm constantly wondering and would love if someone could shed some light. We know ultra processed foods negatively impact your gut health, but is it just down to the lack of good nutrition for your microbiome? Or is there something specific that upfs do to damage it in other words if i eat a generally healthy probiotic diet but stuff myself with pringles and cake on top am i am i okay or am i consuming ingredients emulsifiers etc that then themselves are actively bad for the good bucks great question i think this is well everyone wants to know this can they cheat you know scoff whatever they like and uh be immune like Superman or they don't have to worry.

11:30Let's go back to the definition of UPFs because that's quite controversial. The sort of standard definition now is an epidemiological one used in research, not used commercially, but it incorporates about nearly 60 % of the foods in the UK and the US. And it's too broad. So it includes additives, like someone's added vitamin C to a product, it gets labeled as UPF. I mean, Ella, you know this because you've got food products and you know how on a tightrope it is. We recognize that perhaps half of these UPF products are not really that harmful. The additives, maybe a bit of color just because it comes from carrot juice or something.

12:13I mean, it's generally a sign that less care has been taken with that product compared to something else, but they're not all bad and there's no harm in having a bit of extra vitamin C. So we've recategorized UPFs at Zoe, and you can get that in our new app. It's a gradient from zero risk, low risk, medium, or high. Are the additives harmful? Are they proven to be harmful, not just an additive that we know is fine? Is there evidence that they've been designed to make you overeat, so-called hyperpalatability, by mixing the sugar, the fat, and the salt, like in your Pringles? Are they super calorie dense?

12:55And so they're packing lots of stuff into very little, so you don't notice you're eating it. And are they designed really to not be swallowed? So you just instantly disintegrates into your mouth and therefore, before you know it, you finish the whole pack. All of these are really increasing your intake of those foods. So all of those are important. The main ones have effect on the gut health of the fact that they virtually contain no fiber. Most of these, what we call them now high risk process foods rather than ultra process foods, which in nutrition science doesn't really have a, it's not a defined meaning for it as an individual level.

13:35So these high risk ones are the ones really to be avoiding because they're associated with poor gut health. So We talked about emulsifiers. So Pringles is the perfect example that just about does everything. It's got about 30 ingredients, additives. It's got artificial colorings, flavorings. Potato is not the number one part of the product either. It's a sort of mash of rice and other grain, whatever's cheap. And they've got emulsifiers in there. They've got glues. They've got gums. All of these things, plus they probably throw in a few other things that will mess up your gut microbes. So yes, they have an effect on your gut microbes.

14:15At the same time, you're eating foods that have actually no fiber. So you're starving your microbes in the lower part of your gut at the same time. And they're triggering partly through your microbes to your brain to keep eating more and more and override the fullness signals that normal food would give. So it's a sort of broader idea. This is what we need to be frightened of. And that's why these new scores are actually very good at combating what big food is trying to feed us. And I think that's really important that people, by learning how to score food, you can actually see what the companies are desperately trying to get you to do.

14:55And so we need to be fighting back. And the way to do this is to understand much more about these foods. but essentially once you do that only about half of the foods that are labeled as upf are really high risk foods that we should be avoiding the rest are not really we should be worrying about at the moment so helpful i think what you've done with the um well trying to reclassify you know and educate and not fear monger is a real really wonderful thing because i think the subject of upf foods can be so emotive for people you know can instill a lot of shame if Pringles are something perhaps somebody bought every week and didn't know.

15:33It can stem down on a multitude of levels. And based on what you've just said about us, we know 96 % of us are fiber deficient in the UK. Our diets are not up to scratch, are they? We have to face that head on, I think, because that obviously plays a huge role. But does it link back to mental health? We know the SMILES trials show diet can be effective. But a question we've got from Amy for you, Tim, I think stems on to the fact that diets help our gut flourish, essentially. And she said, if I increase the number of types of bacteria in my gut, can that help reduce anxiety and depression? Yes, is the answer.

16:15And the evidence so far, which is still evolving, is that we know that people with anxiety and depression have poorer gut health than people that don't. So they have what we call dysbiosis, which means a slightly dysfunctional gut microbiome. And you'd find that you'd have a greater range of those bad microbes producing pro-inflammatory chemicals, so irritating the immune system, and also perhaps changing some of the neurochemicals that would eventually go from the gut to the brain via various mechanisms. So we know that, but that's correlation. Then we know from a number of studies, you state the SMILES trial, which was basically giving people a gut-friendly diet for a couple of months.

17:01In Australia, for people with mild depression, that worked very well compared to placebo and even on people on medication. There have been a number of probiotic studies that have shown benefits for anxiety. Lots of studies, probiotic studies on people with stress, reducing stress, and they even got some volunteers to go into icy water and see how they felt with and without these probiotics. Lots of these studies are quite small, but the overwhelming evidence is that they are moving all in the same direction. And we've just did a big study at Zoe of, well, we've done two studies really that both improved the gut microbiome.

17:45One was with our prebiotic, which is like a fertilizer for the gut microbiome called Daily 30, where you're getting 30 freeze-dried plants and you make a big improvement in your good microbes that way if you're tracking the gut health. And those people got big improvements in mood and energy, which I think are a key that it is affecting the brain. And that happened really in the first week often. And another study we did, which is a fermenting study where we took 9 ,000 people who weren't into fermented foods, asked them to go to three a day. And of the 5 ,000 that did manage the three a day, over half of them noticed improvements in mood and energy and reductions in hunger, all going through the brain after about a week.

18:35So I think this clearly shows that there's enough evidence both cross-sectionally and with these gut-friendly interventions that you can impact anxiety and depression. And it's probably through the immune system. There's a whole new neuroscience going on saying we have to rethink all about mental health. And probably it's inflammation in our gut that is being sensed wrongly by the brain, sending signals to the brain to go into lockdown the same way we would do when we're ill, either causing anxiety or depression, depending on perhaps genetics or some other factor. But you can effectively reverse that or reduce it if we really paid much more attention to the gut where it's actually coming from in the first place and stop thinking that it's the brain that's controlling the body.

19:28Actually, the gut in this instance is controlling the brain. Tim, when it comes to fermented foods, what are your favorites? What do you enjoy? Having had to make nearly every fermented food possible for the book, I've got a few weird ones that I wouldn't necessarily expect everyone to make, which is like a fermented mushroom pate with a hint of garlic in it is one of my favorites. It's a bit of a rare one. It took me a long time to get it right because my mushrooms turned off a bit gooey most of the time. So I sort of felt I've done my time on that one. But I mean, my regular ones, milk kefir, I really like water kefir, Tibicos.

20:14A, because it's super fast. You can make it less than 48 hours and you can add any flavor you like to it and make it fizzy or whatever. So it's totally flexible. And until I did the study, I thought it would be less powerful than kombucha. But actually, when we sequenced it, the results are in the book. The top brand came up with about 80 different species in there. Wow. And we know a lot of people don't like dairy products. So I think that's something that really should take off in the future. I think there aren't enough people making really good water kefirs. What is the best brand if anyone wants to buy it?

20:51Agua de Madre is one. but they've just converted to cans and I'm a bit wary about cans. Okay. So if you can still get the bottles, then go for it. But this is the problem in this whole field is if you can get the local one doing great near where you live, support them, you know, whatever it's kombucha, kefir, kraut, they'll always be good. It's when they have to try and scale up globally, they've got to make compromises. This could be the cure to my sparkling water addiction. Oh my goodness, this is the new drink. We've got to start making it. It's so easy to make yourself though. You just get these little crystals and all they need is water and sugar.

21:33And that's it. Very easy, very simple folk. Where do you buy the crystals, Tim? I just get them online and it doesn't seem to matter. They all seem to work. I'm going to give it a go.

21:47Can I ask you very quickly, Tim, because I know that all our listeners will want to hear this as well. So controversial subject, but I feel like we just have to bring it up. GLP1's Marina wants to know, and of course, this is a very new area, very, very new happening as we speak, but how they affect the microbiome. Well, we have very little data. So interestingly, all the trials that were done ignored gut health completely, because generally pharmaceutical companies want to avoid it because if they find a problem, they have to do something about it. and the regulators don't ask them to do it. So they're business people.

22:26They just want to get their drug out on the market. So until people start making a fuss about gut health, this is going to keep happening. The studies out there have been tiny and shown some improvements in gut health. We're just analyzing our data now because obviously with 300 ,000 people, we've got a few thousand that have taken GLP-1s. But it's quite hard to know because most people be obese, therefore they would have worse gut microbiomes, especially if they've got diabetes as well, than the average person. So what we need is longitudinal data. So I'd say I don't know, but there's nothing to suggest that it's very dramatic.

23:05And so it's certainly not a reason to not take them. I'm generally pro these drugs for anyone who needs them. I think they're an amazing breakthrough. Some of their big impact could be nothing to do with weight. It could be reduce inflammation, for example, and help the immune system. Yeah. So it's not a reason to not take it, but we desperately need more research to look at the subtle changes. And there might be reasons to take probiotics or fermented foods as well. But I think in general, we should assume we need all this stuff and we assume we should always look after our gut microbes, whatever drug we're on.

23:42That's not something that doctors and GPs talk about. No, although it's exciting to see, obviously, how much space gut health is now taking up in terms of the conversation in health and wellness. I really liked this question from Steph, which was, she wondered what surprising things affect your microbiome, the things you might not expect in both a positive way and a negative one. Well, yeah, a lot of people take antacid tablets, things like a meprazole called PPI drugs, one of the most commonly prescribed drugs. I think over 60, I think about a quarter of people are taking them. They change the acidity slightly of your gut microbes.

24:21Although they help reflux and acidity, they will mess up your gut microbes and make it more likely to get infections and things. So that's a sort of a downside. Obviously, if you share a house with a coffee drinker and you're a tea drinker, you will get their coffee microbes inside you. Wow. That is unexpected. There's one microbe called Lawsonobacter that only drinks coffee. And if you've got it, you've got 10 times the levels of a non-coffee drinker. but you get some intermediate levels if you happen to your partner or whatever is a coffee drinker because we do exchange bodily liquids with these microbes.

25:08Do you have to be a daily coffee drinker to have high levels or can you be like the occasional coffee drinker? Occasional, I think, yeah. You may not have as high a level as that, but we're getting microbes from everywhere. We share them with dogs as well. Interestingly, some studies show we don't share them with cats. So I have a cat. I have a beautiful cat. So you need a smelly dog is what you really need. Ella's got loads of dogs. I've got three. Three smelly dogs. I've got a smelly dog from me. So your dog will have some of your microbes and you'll have some of your dog's microbes. And what about sleep, Tim?

25:43All they've shown is that the microbiome is disrupted in people who have poor sleep or are doing shift work. and we believe the gut microbes have their own little internal circadian rhythm as well. And so they'll be thrown off track and then we'll be producing random chemicals and things like that if they're not looked after. So they like everything to be at the same time. And that's why in a way things like intermittent fasting affect them because they want to know when to rest and And they don't want you randomly, you know, 11 o 'clock at night, suddenly having your packet of Jaffa cakes. If, you know, they thought they were settled down or they could start cleaning up, you know, and suddenly you're sending more stuff down.

26:33So very much sleep is very much part of the body's homeostasis and keeping things regular. So that is important, but there's nothing specific that we've found yet about sleep. Tim, goodness me. I think everyone's minds are a bit blown with the, particularly the sharing of microbes. Just to sort of, because we're getting to the end and there's too much to ask you. It's such a shame that we have to only select a few. When we say we had hundreds of listener questions, we literally did. Well, this can be part one, really. So, you know, we can do a part two. Thank you. I appreciate that so much. Because I had to give one of the questions we had to your colleague, Sarah, who dropped in my DMs and wanted to ask you a question, Tim.

27:17So Sarah Berry. Oh no, I don't like her questions. She said, what's the biggest thing in nutrition that you've changed your mind on in the past 10 years and in brackets since working with the talented Sarah Berry? Well, I should ask her that question the other way around, but lots of little things. I'm trying to think what the big things are. Yeah, subtle changes on fat, I think. So she's convinced me that I was too strong on butter versus margarine. But butter is definitely better than the old margarines. But she's convinced me that the latest ones are actually probably healthier than butter.