Cholesterol Research and Homemade Kefir Risks

BBC Sounds, Music, Radio Podcasts Hi, I'm Xing Singh, and I'm Simon Jack, and together we host Good Bad Billionaire, the podcast exploring how some of the world's richest people made their fortunes . And we're back for a new season with a brand new lineup of billionaires. Yeah, global pop icon Beyonce. Hollywood movie director Steven Spielberg. Football superstar Christiana Renalo, anyone? And as ever, we're asking you to decide whether they're good, bad or just another billionaire. That's good, bad, billionaire. Listen first and BBC Sounds. Hello, I'm Greg Foot and welcome to Slice Bread, the show that investigates the Wonder Products promising to make you happier, healthier, or greener. Each episode, we follow the crumbs of evidence to find out if one of your suggested Wonder Products is indeed the best thing since Slice Bread, or Marketing BS, and today's suggestion comes from Amanda Kay in Edinburgh. Hello, Amanda. Hi there. Tell us the wonder product you'd like us to investigate today. I'm curious to find out whether Kafir, the drink or the yogurt why it's so good for us. I mean, this is something you see in the dairy aisle of the supermarkets, isn't it? If you're listening and you haven't spotted these, Kafia is spelt K E FIR tends to come in bottles or tubs. How do you consume it, Amanda? I started off mainly using it as yogurt, but then they didn't have any yogurt the other day so I bought the drink and now because I have it for breakfast on either sliced banana or cereal, the drink actually is better . I also partake in a bit of kafia drink. Here it is Biotafall's gut health kafia drink. I just pour this on my breakfast store. Sometimes I have a little swig if I want to feel healthy. Do you have a brand that you go to all the time or is it just what's cheapest and what's available? It's kind of what's available really. One I've got is the same as what you've got at the moment. I think it was an offer in the supermarket . So what health benefits have you heard consuming this can give us? I've heard that it's good for your gut and digestion, improves immunity, cognitive function and mood and maybe lowering cholesterol . I'm interested about its properties and how good it is for you because I had a kidney transplant seven and a half years ago so I have a suppressed immune system it was actually a friend who has had gut problems and he said, Oh, I should be taking it because it's good for your gut. But it's kind of how much do you have to consume? Yeah, good question. I've also seen that this bottle makes a point of saying no added sugar. Is that something that concerns you? Yes, because I never really understand what no added sugar means. Well, you're not alone in being Kafir curious as you say, Amanda. We've got loads of questions about it emailed over to sliced. bread at bb.c com. Here are just three of them. Ishmael asks whether Kafir is healthier than live yogurt. Emily asks if there is an effect, how much does she need to drink to get it? Same as you ask there, Amanda. And Adrian has noticed that some kafirs have more strains of bacteria than others and asks if that makes a difference. Well, to help us answer these questions a more, let me bring in today's expert. He's very cultured . My gut says that he will help us get to the bottom of this. Sorry, that was ferment to be a joke. Yeah, good. Right. Joining us remotely from County Cork in Ireland is the head of the Food Biosciences Department at the Irish National Research Body Chargus, and he also is currently leading part of a major European research project into fermented foods, Dr. Paul Cotter. Welcome, Paul. It's great to be here, Greg, very nice to talk to you and Amanda. A question I ask everyone, Paul is, do you have any affiliations with any companies, any conflicts of interest as we call it? There's a few different companies that we've performed research on their Kefeirs, or we're giving them some advice relating to what they can or can't say about Kefeir in general. But do you feel like you can speak freely about what the evidence base is around these products? Yeah, most definitely. Okay, let's start at the beginning pole. What on earth is Kafir? So Kafir are kefir or there's very many different ways in which people could choose to pronounce it. In essence, it's a fermented milk. And traditionally before you started to see it more frequently in supermarkets is a product that people made in their own homes using what's known as a kefir grain. It's kind of a clump or a cluster of microorganisms, good bacteria and good yeast that are bound together so kind of a gloopy looking material. It looks a little bit like a small cauliflower. If you pop these kefir grains into some milk and the microorganisms that are in the grain some of them fall off and they start to grow in the milk and they carry out the fermentation and you leave that there for maybe twelve or twenty four hours depending on how you like your kefir. You remove the grain again so you can keep that to make some order the next day and you drink the milk. And for anyone listening to this and thinking, hang on, why would you opt to drink bacteria? You did mention that these are good bacteria in the cafe grain. I mean, that's the whole point, isn't it? Exactly. There are more bacteria out there that can be good or are harmless than the bad ones in general . And I guess the appreciation of good bacteria has probably increased in recent years now that the whole concept of probiotics is in the public consciousness, we're consuming microorganisms on a daily basis in our cheese, our bread and wine and beer, kombucha, kimchi, all sorts of other things. Amanda are you pro good bacteria consumption? I should be . As I said, because of my immune system being suppressed , I want to try and do the best to keep me healthy. And are all Kafir grain s created equal or do they vary? Most definitely they are not . They are kind of first cousins of one another, so there tends to be some general rules. So you will often find some lactic acid bacteria there, some other types of microorganisms called acetic acid bacteria and generally some yeast. But there are lots of varieties and indeed we've done some surveys of different kefir grains that we've sourced from around the globe and do see quite a bit of difference. Would you notice the kefir tasting different? The most obvious thing will be the duration over which the fermentation takes place. If it's over a longer period, you will have a stronger flavor that will be more acquired. If you carry out the fermentation for a shorter period, it's a bit more like yogurt and more popular for the general public. But you can't tweak things in the past we've established that certain types of microorganisms if that's more abundant you will have more of a buttery flavor in your kefir. Others, you might have a more fruity flavor and then acetic acid bacteria as the name suggests would produce more acetic acid which is, kind of of more a vinegary flavor. So you have various different ratios of all of these things. Fascinating. As Amanda said, there's also the yogurt kafir as well. They're often around the same price. So Yovalley's Kafir yogurt costs four pound fifty for a tub that's about a kilogram. Their drinking Kafir is priced similar in a half bottle for two hundred fifty so it comes at around five pounds a litre . There are cheaper options. Artler sell their organic kafir drink in liter bottles for just under three pounds. And you can go way the other way up the scale. You can get much more expensive Kafir, listener Adrian asked about a brand called Chuckling Goat, whose original Kafir drink comes out of close to fourteen kid elite . It's a lot, isn't it? Yeah. One way that the products differ, as listener Adrian pointed out in his email is by the number of strains of live cultures that they claim are in their Kafir. Now, it tends to be that the more you pay, the more strains they claim are in there, but it's not a perfect linear relationship that works every time. Paul, how can these brands make specific claims about the number of specific strains of cult liureve in each b ottle. So there are two ways in which kefir is made. As I mentioned earlier, it can be made in your kitchen with these kefir grains and some manufacturers are continuing to rely on those grains for larger scale production, they do an analysis to see how many different strains are present in that natural process . So in that case you're likely to get more strains because you also have strains that are coming from the milk and from the environment, the numbers expand over time and can change. The microbes can evolve and the population can't change. The alternative approach is whereby you study the kefir grain and you either pluck out specific strains or you buy them from a company that sells strains and you add them to the milk but without the kefir grain. So you're not using the original natural process, but you're adding what are known as starter bacteria and then some others will add some extra strains for marketing purposes and try to impress the consumer and make them be willing to pay more money even if those strains sometimes aren they't doing much of anything. Hang on a minute. So you're saying that you can create it naturally as you say, but there's a second method where they add specific bacteria to make it resemble the natural version and potentially for marketing purposes. So in some ways does that mean it's not real kafir? The enthusiasts will argue that yes it should be made with the original grain. I appreciate that argument, but I think ultimately if you, have a combination of strains that quite accurately reflect what's present in the grain, then that's good enough. Amanda, what do you think hearing this? I'm surprised. I was just looking at the bottle I've got of the ingredients to see whether I could tell if it's got the grain in it all or not and to be honest I can't if they're using cultures then those are the starter strains that I mentioned but at least they are kefir cultures which means they are Kef ir strains rather than being sourced from a yogurt or from some other random source. Interesting. And Paul, crucial question, would you suggest going for a Kafir product that has more Kafir strains than one that has fewer Kafir strain s. Not necessarily. Somewhere between eight and fifteen strains is probably about right. You can make something that resembles a kafir with three or four strains, but I think up to seven or eight is probably the minimum to ref lect a true scenario. And just before we get onto the health claims, the back of this bottle I'm holding does list some of the cultures that are in this bottle . Are there any that you would suggest people should look out for? So you should find things like lactococcus lactus, other types of lactococci , acetobacter, leuconostic, different types of lactobacillus . And not everybody adds them, but if there were some yeast such as saccharises, that's kind of a bonus. Well, let's have a look at the health claims. So Amanda, the first thing you mentioned was gut and digestive health. Lots of other listeners have asked the same thing Paul, is Kafir good for your gut? I might take a step back and this might shock people when I say it. There are various different agencies in Europe and other countries that decide whether you can put a claim on food as to whether it's health promoting or not. So despite all of the research relating to Kafir, there isn't a specific health claim that you can attribute to Kafir or any other fermented products. They can say gut friendly or put on a picture of a stomach with a smiley face on it, but in terms of a specific health claim, they're restricted from going any further. That's essentially what we see on lots of these different products. So there is emerging evidence that just having more good microbes in your life and in your diet is good regardless of where they're coming from. So that's general for all fermented products, but there are lots of live microbes in Kafeir, so it ticks that box. What about the gut microbiome? Lots of listeners have asked about whether Kafir improves the bacteria inside your gut . We didn't see any products making specific microbiome related claims, but Paul, do we think that consuming kafir strains of bacteria can help our gut microbiome? The influence can vary. Sometimes you can see some of the microbes that are being consumed in the Kafeir in the gut subsequently . Sometimes the effect is indirect. So instead of seeing an increase in those microbes, you see an increase in other microbes, the ones that are already in the gut . Sometimes you see the effects not through the changes in the microbes that are there in the gut, but rather what they do. Right. Okay. So it sounds like you're suggesting there could be improvements to your gut music robiome through a couple of different mechanisms and that can therefore help your gut health as well potentially. Yes. Can I just ask about the gut health? If it's helping improve your gut health, what does that mean that you don't get so much bloating, that you don't get indigestion, constipation ? So gut health is a very broad term . Within that, it could be any number of twenty or thirty different things , including all of the ones you mentioned. Gut health can also relate to just IBS, irritable bowel syndrome type symptoms, diarrhea, constipation, and it may be that certain kefeirs will be good for addressing one or more of these, but it is challenging for us when somebody ask us about gut health in general because it involves so many different aspects. So if you've got gut tissues, should you be drinking it to try and sort those out? I think for addressing some mild issues there's no reason why not and it can have a beneficial effect . For some other extreme gut conditions like inflammatory bowel disease and the disease that fall into that category like Crohn's disease , then that's a bigger issue and there is no evidence of being able to address that. Okay, let's move on to some of the health claims that we've seen that I want to bring up. Biotafal Kafir original use the phrase quote, a tasty way to support your gut health and immunity naturally. Although they justify that with an asterisk that says source of vitamin B twelve which supports the normal functioning of the immune system. So it's very interesting that they're pointing to the Vitamin B twelve there as the the support for normal function of immunity, not the fact that the milk is fermented, or that it's packed supposedly with live cultures. Paul, what does the evidence show around Kafir's support with your immunity or your immune system . Anything more than vitamin B twelve? Because of the limitations in terms of health claims relating to fermented foods, you do find a lot of companies that make these products will add in some other supplements in order to allow them to put other things on the label. So it sounds like, correct me if I'm wrong, any benefit here for the immune system or immunity support is coming from the B twelve edition rather than the addition of the live cultures. At least in terms of the health claim, but the science would say that consuming cafe will in general be good for the immune system. Where does that leave you Amanda? What do you think? Well, I'm kind of wondering should I just be eating natural yogurt and I'd be getting the same benefits rather than paying more for the kafir . I would still consume the kafir because yogurt is a very simple dairy product. There are just two strains in there and those two strains are generally just added to cause the yogurt to clot and give its yogurt feature . So those types of microorganisms are fine for that purpose but not necessarily great for health. On to the next health claim I, saw chuckling Goat claim that their probiotic aphere supports normal cognitive function, neurotransmission and the health functioning of your nervous system. But similarly, to before, those claims seem to be linked to specific nutrients in there like magnesium and iodine not to the live cultures. I'm not surprised by that again because you're limited in what you can put on labels. So we know from our research that there are undoubtedly some kefirs that can have beneficial effects in that regard, but you would need do a detailed study in order to establish definitively if your strains are capable of doing that or not. Do you feel like the science suggests that there are potential benefits for cognitive function, mood, nervous system, but the evidence level isn't at such a point yet where the UK's list of legal health and nutrition claims say you can add it to the bottle. Exactly. The gap to be bridged there, and we're doing a lot of this in our lab and very many other labs around the world is to figure out which are the right kefir strains to get into the right product so that the people that are specifically looking for a version that's good for their mental health or cognition get that version. But I think we're still a few years away from getting to that point. What about cholesterol? I mean, I've seen one company happy Kombucha, they sell Kafir grains. I'm going to get onto the homemade in a second, but they claim that Kafir can quote help to control high cholesterol levels. Is there any research to support that , Paul? There's quite a bit of research, including from Earlab in that regard. So we took some natural keffer grains and we put them in whole fat milk to determine which of the grains were good at reducing the amount of cholesterol in that milk. And we found that from that maybe of fifteen or twenty tested that slightly less than half of those grains were able to do it. And from those grains that gave a positive result, one was successful.. Wow So very dramatic differences in cholesterol and other various different immune biomarkers as well, which was great . Production with the grains can cause some fluctuation. The product that you get today might be different from the one you make next week or next year. So that makes it challenging to produce that product on a large scale and in a consistent manner. So what we've since done is we've plucked out some of the microbes from that cholesterol reducing natural grain and kind of put it back together like the strain approach that I mentioned earlier. And so in that regard we can successfully recapitulate the effects of reducing the cholesterol. Fascinating. So it sounds like some specific bacteria strains, some specific kaffia strains of bacteria show some effects on your health. But the question is are those specific kafia strains in the bottle of kafia that Amanda or I are pouring on our breakfast. At the moment, it wouldn't be clear. You'd need a lab like ours or other labs that work in the space to get that product to gout the individual strains and study them in depth, but those strains more than likely have not been selected specifically for that purpose. Would it be better to make the yogurt at home? I appreciate a lot of people don't have time to do that but I do. The product that you make at home'.s It quite often as good and potentially better than a lot of products on the supermarket shelf . My kind of slight frustration with the product that you make at home is that it takes time, but also you need to look after your grain . For people who are old enough like me to remember the tamagotchi, you kind of have to look after your grain and maintain it and make sure it doesn't die. Are there any risks of making your own at home? Because I heard about people kind of saying you want it to fizz and pop when you take the lid off, but will it ever fizz and pop a bit much? That's one of the reasons I brought up yeast earlier because if there is a fizz and pop that's probably reflective of the presence of yeast and most people will want that. If they don't get that, they would argue it's not a real carefare. I wouldn't quite agree with that. I think the main risk is just standard hygiene processes that the milk you use is fresh, that you're not using milk that's just about to go off anyway. In terms of the gas production, it's not so extreme with milkfare. You should use a dedicated container that will either allow the excess gas to naturally be released or that you open it sporadically to allow the gas to be removed. I haven't heard this concern so much with Kafir, but I do know that with some other products like water, Kafir or Kombucha, that if you put in a container that's not appropriate for purpose, you can have issues of exploding bottles and whatnot. And a question that Amanda asked and a question that listener Emily emailed us to ask is how much kafir you'd need to drink to have these potential benefits that we've been talking about? There's no set and hard rule. Ag itain com,es back to what strains and so on are present, but ultimately I would drink a hundred mils or thereabouts. Okay, and just while we're talking risks, is there anyone who shouldn't consume Kafir? If somebody was on very extreme immune suppressive drugs , then exposure to any large numbers of microbes might be a potential risk factor. But I think for people who, Amanda mentioned that she is mini immune, suppressed. I think in that case there isn't any great harm , but I also do generally recommend people when they're beginning to consume a new fermented food to maybe try one, get into the habit of having a food diary where they take note of what it is that they're consuming and how they feel for the next couple of days. And if you have any side effects, then maybe pause that and move on to something else. Good advice. Does flavoring the Kafirpool compromise any of these potential health benefits? No, not really to my mind. We talked about sugar earlier and we wanted to know about the sugar levels in these products. So I went on a little supermarket adventure to have a look. So on average, flavoured kafirs do contain more sugar than plain kafir but the sugars tend to come directly from fruit. Amanda we discussed briefly earlier what no added sugar means. So when products say this they can't include any sugar or sweet ingredient added , quote, for its sweetening properties . But the advertising standards authority said that they judge this on a case by case basis, so you might see a flavored confir that says no added sugar and that's because the sugary fruit puree is technically there for its flavoring properties, not its sweetening properties. So no added sugar doesn't necessarily mean low sugar, but in this case it, does seem to at least mean natural ingredients. That seems reasonable. Okay, let's get into water cafe because I'm fascinated by this. It's a bit harder to find in supermarkets, but we did see Holland and Barrett sell cans of one living lemon water f kair drink for two pound thirty, which works out at just under ten pounds a litre. You can also buy it from specialty shops or online. One brand Peeky PIQI had ginger and lemon Kafir water just over fifteen pounds a lit er. Paul, what is it? Is it just water plus these genuine Kafir grains? For the most part, the other main ingredient is sugar because that's carbohydrate source for the microbes and it frequently will have fruits in it to add flavor. And I guess it's called kefir because the type of manufacturer is somewhat similar to milk kefir in that it involves grains . But in this case, the grains look quite different. They kind of look like the translucent crystals which are added and the microorganisms present are somewhat different. The approach and the use of grains is what results in the same name being used, but they are quite different products . Okay , so do they have similar potential as some of the milk cafe products that we've been talking about? The evidence relating to water cafe is much less. Fewer studies that have taken place. We're doing some now, but it is quite a few years behind. Well, I think it's time for the final question, Paul. Is Kafir the best thing since sliced bread? Yes, with an asterisks. Yes, I would encourage every body to drink milk cafeir, but you also need to be careful about how you interpret some of the marketing. Are there some milk cafeir products that we can buy in the supermarket or online that do have more promising kafir strains in them. We don't know. Wow, okay . But for you, there's a benefit in drinking them because they're fermented in general. I would encourage people to consume fermented foods and beverages in general, but there is more evidence relating to milk cafe than a lot of the others. I can consume it regularly myself. It's why I recommend if somebody asks me what this should start to consume if they're getting interested in fermented foods, it's always the number one that I would recommend. Amanda, final word on this goes to you. Are you going to stick with your cafe drink? I think I will carry on with it, particularly because of my health issues that if it can help, I might as well. And will that be one you buy from the supermarket or you're gonna have a go at making it yourself? It'll probably be off the supermarket shelf because it's easier. Yeah . Well, with that, I shall wrap up this episode of Sliced Bread. A big thank you to Amanda and Paul for joining me. And if you're listening to this and you're thinking, Greg, I have a wonder product I would really like you to investigate, please do send it over, either on email to Sliced dot bread at bc. co or as a message or a voice note on WhatsApp to zero seven five forty three six eight seven Next time , many of us have heard of antivirus software and firewalls, but what about a VPN , a virtual private network? They are widely advertised on podcasts and social media as must have for computer security and privacy, but what are they? And are they really essential? I'll be finding out. See ya . This episode of Slice Bread was researched by Phil Sansom and produced by Kate Holdsworth and me, Greg Foot, our studio manager was Kelly Young, and Slice Bread is an audio northion for Pro BductBC radio . I'm Dr. Chris Van Talken and I'm Dr. Zand Van Talakin. Chris, it's that time of year when we set resolutions. It certainly is Zand, and that is why in January, our four episodes of WhatsApp Docs are going to be on the key themes that feature in resolutions alcohol, food, exercise, and the whole notion resolutions themselves . Can we change? Should we change?