The Insulin Sensitivity Playbook: Vinegar and Glucose with Dr. Carol Johnston

[00:00:00] Rob Howe: Welcome to the Diabetics Doing Things podcast, where we share the amazing stories of people living with diabetes from around the world. Since 2015, this show has been dedicated to exploring what it actually takes to live well with diabetes. I'm your host, Rob Howe. I've been living with type 1 diabetes since 2005. I'm an entrepreneur, an athlete, and a diabetes advocate. The focus of this podcast is to explore what it means and what it takes to live well with diabetes. We do that by tapping into live experience and guest expertise with the goal of giving people with diabetes free tools, language, and perspective to help unlock their potential. That means looking at life with diabetes through four core lenses, physical, mental, social, and financial. Because living well with diabetes isn't just about managing numbers. It's about navigating an entire life. At the same time, we don't ignore the obstacles. We acknowledge the weight, friction, and the real challenges that come with a life with type 1 diabetes. And we talk honestly about how people navigate them. If you want to go deeper, you can subscribe to the podcast and our newsletter at subscribe.diabeticsdoingthings.com. And for more information about our work, visit diabeticsdoingthings.com. Guys, who was MVP of the chat? Hello, welcome back to Diabetics Doing Things. We're telling the amazing stories of people with diabetes from all over the world. And I'm on an interesting path. As listeners, you know, I am trying to really dig into what it takes to live well with diabetes. And my guest today is Dr. Carol Johnston. She's from Arizona State University. I'm calling from Phoenix, Arizona today. And, you know, your reputation proceeds. Those call you online the vinegar lady. We're going to talk a lot about vinegar and blood glucose and how vinegar might be able to help somebody out there listening who's living with diabetes. So, Dr. Johnston, thank you for coming to the show today.

[00:01:49] Carol Johnston: Oh, you bet. I'm happy to be here and I'm happy to tell you all that I know. It's an interesting story.

[00:01:56] Rob Howe: Well, I'm excited to dig into it. I got to say, I am on record and my wife could attest, I am not the person who loves pickled things. I'm not a person who comes by the taste of vinegar naturally. So this has been something that I've adopted. But since I have really dug into your story and your research, even today before lunch, alongside my meal, I had a little bit of vinegar in my water with my meal. So we're going to talk a little bit about your research today, which kind of starts, I think, closer to about 20 plus years ago. I've heard the story on another podcast that you were digging through research journals, which is not as easy back then as it is today. And you uncovered something from the 80s that sort of started you on this path. So why don't you introduce yourself and talk about that?

[00:02:40] Carol Johnston: Well, I'm Carol Johnston. I'm a professor in nutrition, and I'm also a registered dietitian. I'm at Arizona State University, which I've been here now. This is my 40th year at the university, and I run clinical trials. I'm real interested in trying to identify dietary strategies that are simple, because I know from my research and my studies that people won't make major changes. They might do it for a short period of time, but they won't like adopt major changes. And so these simple diet strategies have been my focus. And so back in the 90s, I was very interested in these high protein, low carb diets because I was working with a diabetic population and these diets are helpful. The high protein, lower carb diets are very helpful. Obviously, if you consume less glucose, you're going to have less glucose going into the bloodstream. So it was very clear and we ran quite a few trials and we had great success. But I picked up very quickly that the participants who were often diabetic in these situations, they wouldn't adhere to these diet plans after the study was over. Not very sustainable. And so that's when I started looking at the literature to write up these studies. I had to look at the literature and review it. And I found this one rat study. It was a 1988 study. It was very obscure. I don't even think it's indexed right now in the major indexes, even to this day. But in that study, they had a diabetes-prone rat, and they were feeding it vinegar, and they were seeing the same results that I was seeing from these high-protein, low-carb diets. And so, in other words, they had this simple strategy. They fed these rats a high-fat diet, you know, diet that would only extenuate their condition, and then they gave them vinegar or a placebo and they saw like these pretty significant impacts on their blood glucose. And so I thought, okay, it's in the late 90s, 10 years later, who's followed up on this? Because I was certain somebody would have followed up on this because it was such an interesting finding. And I didn't find anything in the literature. So I conducted a very simple study where we had individuals who did not have diabetes. We had individuals who were pre-diabetic, you know, at risk. And then we had type 2 individuals with type 2 diabetes. And we simply did a very simple study. We fed them bagels, which will make your blood glucose level spike. And they either had a placebo or they had the vinegar. And I saw the effect. And I have to say, I was a little shocked. And I was a little concerned that people wouldn't believe me. Interesting. Because vinegar, it's sort of fringy. It's not what you would consider to be hard science, consuming vinegar. And so I thought, well, I'm going to try to get this published. And I went to the top journal in the field, Diabetes Care, which globally, it's one of the highest practitioner read journal on diabetes. And they accepted it. And I have to say, I was very nervous that I would be rejected for something that's like, come on, this is really silly kind of thing. And it was accepted. And that paper was the first paper on vinegar with the diabetic condition. And that was in 2004, as you said. So now it's been over 20 years. And I have to say that I was a little nervous. I mean, I'm getting published in a top tier journal that's globally read. And I was a little nervous of kind of the feedback I'd be getting on this. And I was quite relieved when others started publishing. And as you know, one study is not the say all, you know, end all, say all. You need to have multiple investigators in multiple countries finding the same results to feel good about how strong your data is.

[00:06:37] Rob Howe: There's something about vinegar. Maybe it's just so simple or maybe it's just so ubiquitous. It's not very sexy, right, to say that vinegar is this great treatment. because it has been reviewed. Again, there's multiple papers and publishing studies published from all over the world showcasing exactly what your first study showed and more. And yet it still is sort of maybe it's a homeopathic type of interpretation from the general public or people kind of like squint their eyes at it a little bit and maybe question it. What has that been like or what other obstacles have you encountered when presenting this research, which is tremendously impactful. And like you said, it gives similar results to a high-protein, low-carb diet, which I feel like every person with type 1 diabetes has explored or at least heard about in some capacity. And yet, you know, a simple dose of vinegar at mealtime can give you effectively the same result.

[00:07:32] Carol Johnston: Right, right. And I do want to clarify at the start that everyone should try to improve their diet. We all need to improve our diets. And so I don't want to say you can eat whatever you want and just take vinegar. You need to make an effort to try to minimize the simple carbs in your diet and the sugar and the fat. I mean, we all need to eat more fruits and vegetables and fiber and all that. So just lay that as a basis. But the vinegar is really interesting. And I have presented this many times, as you can imagine. And I was at one conference and this sort of gives you the picture, the full picture. I was at a conference speaking on the vinegar. They invited me. They wanted to hear about the vinegar work. This is a few years back. And I was speaking mainly to clinicians, to doctors, to NDs. And I gave my pitch and with all the evidence, because there was evidence from other investigators at that time as well. So it wasn't just my work. And after I spoke and came down from the podium and was walking through the crowd, a doctor came up to me, a medical doctor, and he goes, Carol, we have drugs for this. We have drugs. We don't need vinegar. And so I think that's very telling. We do have very effective drugs. We have metformin. Sure. Very effective drugs that seem to be fairly safe, although there are side effects to metformin that can be quite serious. But I think that that's the mentality a lot is that We know we have a drug. The patients want drugs. They want drugs and we have a drug. And, you know, what's really interesting about this is the target of metformin is the same as a target for acetic acid, which is what's in the vinegar.

[00:09:13] Rob Howe: So let's talk about that. Let's talk about the acetic acid because we're kind of getting into like what's happening in your gut at mealtime, whether you have diabetes or not. And, you know, what I have really uncovered in terms of my interpretation of living well with diabetes and my experience of living well with diabetes is insulin sensitivity is a huge part of that. As you mentioned, we can all do better and make good choices about our diet. But when you're living with a chronic illness, the sort of day in, day out repetition of having to constantly make great decisions, I think, wears on people. Yes. And can cause, like you said, lack of adherence to a low-carb or a ketogenic or a high-protein, low-sugar diet. And so when someone wants to have an excursion on their diet, so to speak, often what follows is a glucose excursion as well, a big spike. And so ways that we can, whether it's postprandial walks or vinegar in this case, or other modalities, pre-bolusing your insulin, for example, the more we can lessen that spike or that glucose excursion, the better we often feel, both, I think, physically and psychologically. You know, for me, you know, is it just the simplicity? Is it, like you said, simple solutions? I really resonated with your exploration for simple solutions that are sustainable. But back to the gut, so much of what we talk about in insulin absorption happens in your gut, happens around mealtime. So what's happening with that acetic acid and how does vinegar contribute to that?

[00:10:43] Carol Johnston: Okay. I mean, this is a great question and it's really interesting because vinegar is a fermented product. Okay. We've all heard of the word fermentation and how the gut ferments our food. So understanding that vinegar is a fermented product. And so you take the juices from fruits and vegetables and grains. And there's a process with bacteria and yeast where the carbohydrate, the glucose, is converted to ethanol and then to acetic acid. That's the process of the fermentation. This is what your gut's doing. This is what those microorganisms in your gut are doing is they're fermenting the fibers. You know, because the starches are all digested and absorbed. So what goes into your colon is going to be the undigested fibers, which are basically made up of glucose as well. And so these gut organisms will ferment and produce acetic acid. Well, vinegar has already fermented the carbohydrate to acetic acid. And so you're ingesting the acetic acid, which is the same product that you're going to get from the microbial fermentation in your gut. But what's interesting, so that's, I think, a very important connection to make. When I first started this work in the early 2000s, the whole gut thing wasn't very popular. We didn't really hear anything about the gut. And so I didn't make this connection until the gut microbiome became popular. Studying the gut microbiome and how that's so important for our health, that was about 10 years later, about 2014, 2015.

[00:12:21] Rob Howe: Well, and that's even in the scientific community. I feel like even only in the past five to six years in the general population or maybe health discussion, biohacking, you know, supplemental, how many prebiotic and probiotic supplements are there on the market today?

[00:12:36] Carol Johnston: Exactly, exactly, exactly. And, you know, I made the connection. I mean, that connection is so clear. The main product of gut fermentation that goes into the bloodstream is acetate or acetic acid turns into acetate. A hydrogen is just removed. So it's the same molecule. But what's so interesting about consuming it orally is that when it gets into the stomach and the small intestine, it's immediately absorbed. It's absorbed like four times to a greater degree than if you ate fiber. So if you compared a vinegar, ingesting two tablespoons of vinegar to ingesting a high fiber meal, you're going to get four times the amount of acetate in the bloodstream as you would from that fiber.

[00:13:17] Rob Howe: Okay, so say that one more time because I think this is really important. Because we talk a lot about in the diabetes community, the importance of fiber, the importance of digestion. I think we could even call it gastric emptying, right, in terms of the timing of the exogenous insulin that we're bolusing and the peak timing and all of those things. So say that one more time, because fiber, like when we eat a salad, right, they say like pad your carbs, right, where you put a little vegetables or a salad or maybe even a vinaigrette, which we can talk about a little bit later as well. to pad your carbohydrates before you have a potato, before you have a, if you have a sandwich or something like that, that's a carb-rich meal. It can help slow or I guess slow the spike, but I guess speed up the digestion process from a fiber standpoint. Right. So, and what you're saying is that vinegar is a multiple of that. So tell us one more time. Okay.

[00:14:07] Carol Johnston: And again, I just want to preference that we should all be eating more fiber. Okay. We should all be. But, but the, so when the fiber is fermented in the gut, it will produce acetic acid, which goes into the bloodstream. It's really the only short-chain fatty acid from the fermentation process that gets into the systemic circulation. It is the short-chain fatty acid that is causing metabolic changes. But if you take vinegar, that acetic acid is absorbed in the stomach, in the small intestine. It's way before stuff is starting to ferment in the gut. And so you get a very rapid, within 30 minutes, you get this peak of blood acetate that is four times that for what you would get from the fiber consumption alone. So not only is it a more rapid blood response, it's a much higher blood response. And again, I didn't make this connection in the beginning because nobody was talking about the gut microbiome. So nobody was really talking about this. But as soon as it became apparent that these short chain fatty acids, which acetic acid is the prominent one, is so important for our health, I immediately switched my research from glucose to looking at brain function and even muscle function, because that's what the gut brain, gut muscle, there's all this that they're talking about with the gut. And so, So, you know, I sort of pivoted because the glucose story was already told. But let me just tell your audience how this works. So there's two things that the acetic acid is doing. So, and this is why we tell people to have the vinegar before the meal. And just like what you described, maybe a pre-meal salad with a vinaigrette dressing on it. Or you can dilute the vinegar in water. We can talk about this, you know, exactly how to do it later. But you want that acetic acid to beat the starch into the small intestine. Because what they've shown, not myself, but other investigators have shown, is that the acetic acid appears to block the digestion of starch. And it's a very transient. The molecule is probably moving in and out of the enzyme active site because it's a very small molecule. And it's transient. Like if you took the vinegar hours before the meal, you wouldn't see any effect. You have to have it right at the start of the meal. It gets into the small intestine. It seems to be interfering with the digestion of starch. And so that's the first thing. Because what that means is not that the glucose is not being freed up so it can be absorbed. The glucose remains and bonds with other glucose molecules and it moves into the colon. Okay. Just like a fiber. So in essence, the vinegar is sort of making your starch more fiber-like because it can't be digested fully. It can be digested partially, but not fully. And so you're actually moving more of that undigested starch into the colon so it can be fermented, which is great. So that's one reason you don't get the spike because less glucose is freed up in the digestion process to enter the bloodstream. But the second thing is, as I told you, is you also absorb a lot of that acetic acid. So it gets into the bloodstream at a very high level within 30 minutes. And it can affect muscle uptake of glucose. And so I haven't done these studies, but other investigators have done studies where they have catheterized the arm muscle, where the blood enters the muscle and when it exits the muscle. And it's shown that the vinegar consumption will actually increase glucose absorption into the muscle like by 30%. So not only is there less glucose going into the bloodstream, but the muscle is pulling it out much faster because the acetate is affecting muscle metabolism.

[00:18:05] Rob Howe: So, and again, like this is all just having a conversation here. But for example, those of us who are treating a hyperglycemia with maybe going for a walk or doing some squats, vinegar would augment and increase or maybe shorten the time frame that you would need to participate in that exercise to have the same desired glucose absorption or insulin absorption result.

[00:18:27] Carol Johnston: Okay. And I encourage people to walk.

[00:18:29] Rob Howe: Yeah. I agree. I agree. This is not an anti-walking podcast at all or anti-squat for that matter.

[00:18:35] Carol Johnston: Yes, exactly. But the muscle. So the reason insulin is so important is because insulin, you know, after you eat, a typical person would excrete, secrete all this insulin into the bloodstream. The insulin goes to the muscle and it tells the muscle to uptake glucose. OK, there's a transporter. This is probably way too much information, but there's a transporter in the muscle that is hidden. And when insulin is there, it goes to the surface and it will take the glucose up. Okay? So that's insulin dependent. A contracting muscle will do the same thing without insulin. And so what you're doing when you start walking after a meal is you're making the muscle, you're moving this GLUT4 to the surface of the muscle and it's taking up more glucose. Well, acetic acid does the same thing. Acetic acid will stimulate the reaction process to get that GLUT4 up to the surface. It's amazing. It's amazing.

[00:19:28] Rob Howe: And right now there's also some studies that are going on about postprandial walking and, you know, 10 minutes, both preprandial before meals and postprandial after meals. And it seems like, you know, there's a combination of these very simple, like you said, simple solutions that do not require, they're not expensive. In many cases, they're free. They're not, they don't require a special subscription. They don't require any special credential or a pharmacy or a physician. And they can affect not only for people who don't have diabetes and who are working on their diet and their exercise, but also people with type 1 who I know initially, at least from these studies, like most of the studies were on people with prediabetes, type 2 diabetes, or without a chronic illness. But there's also research now to support post-periandral hyperglycemia decreasing in individuals with type 1 diabetes. So it is extended into like this actually works for almost everyone.

[00:20:23] Carol Johnston: Well, I'll even add, you don't even have to have diabetes because that spike in glucose can lead to plaque development, which is heart disease. And so you can be totally free of diabetes and still have an advantage because those spikes in glucose are very damaging to arterial walls.

[00:20:41] Rob Howe: Well, and, you know, we're looking at the number one comorbidity of people in the United States is heart disease, you know, high blood pressure, you know, cancer, Alzheimer's, dementia. And I know with type 1 diabetes, obviously, like this is a lifelong chronic illness and the number one comorbidity is heart disease. So anything that we can do to keep our A1C in range, more time in range, more percentage in target glucose range is going to be a positive for us long term.

[00:21:08] Carol Johnston: We actually have a study that is under review for publication where we had a glucose monitor on people taking vinegar. And we actually did see an increase of time and range.

[00:21:22] Rob Howe: See, I think this is something where, because I think that there is, and I want to get your thoughts on this as well. Like there is another person who's like very public about vinegar and like selling a vinegar supplement. And like there's a little bit of like in the social media world about this. But I think because of maybe what you mentioned earlier, it's a little bit of like, is this real? Is this just another supplement? Is it research-backed? And so then immediately doing that quick Google search and finding your work just shows that, yeah, not only is this research-backed, there's decades and hundreds of studies that show this.

[00:21:56] Carol Johnston: I just want to mention this because this is really important. If the supplement is a pill, it's not going to work. So I'm not sure what when you said supplement, because they make they make the little shots, too. You know, they have vinegar everywhere.

[00:22:10] Rob Howe: I was going to say, we got to talk about your personal routine.

[00:22:12] Carol Johnston: I don't want to show labels, you know, but you can do the liquid shot or you can take the pill. And it's really interesting because we use the pills as our placebo. Because when you do a randomized controlled trial, you don't want the participant to know which group they're in. Because that can affect the outcome. And so when you buy the supplements, you open this supplement and it smells like vinegar. Because it does have a little tiny bit of vinegar in it. But you would have to consume like 14 capsules in one sitting to have an effect because there's such a small amount. And so we use these. We tell our participants that they're either going to get a liquid vinegar or they're going to get the pill vinegar. And so they just think they're getting vinegar. They don't realize that the amount that they're getting in the pills is very, very small. And it's not going to have this effect. And we've been, like I said, all of my publications, all of them, we have used the pills as a placebo. So I just want to make sure. So the liquid is tough. I mean, it is tough to drink the liquid. And, you know, there's erosion of tooth and that. And I mean, there's there's some concern. You can aspirate it into your lungs, which is very serious because you can burn your lungs. And so we just have to remember vinegar is an acid and it can be poisonous. And so you don't you don't go overboard with it. You do it. You know, if you're going to drink it, you want to dilute it and you might even want to drink it through a straw. if you're worried about your tooth enamel because the acid on the teeth could be problematic. But the other thing we say is have the vinegar at the start of the meal with the first bites of the meal because if the vinegar is being mixed with the other food matrix, it's not going to as likely be in contact with the tooth or even the mucosa, okay? Because if you have any kind of lesion in your mouth or esophagus, it's going to affect that because it's an acid. And so that's why we say, you know, dilute it. If you want to drink it through a straw, that's going to lower the risk on the enamel, but also to have it with the first bites of the meal. So you're mixing it up with this food matrix.

[00:24:17] Rob Howe: Well, and like you said, that also contributes to the primary benefit, which is on the digestion side, right? So the timing of it is important. That's something I want to get into maybe towards the end of the conversation is just like the, you know, in mathematics, you have an order of operations and you also have that in eating and digestion health, you know, in terms of the timing. But I want to talk to like around your desk, like what's your protocol for integrating vinegar into your everyday?

[00:24:43] Carol Johnston: day? So I have to, I don't have diabetes and I don't have it in my family. So my family is cancer prone, but they're not diabetes prone. And so I don't have any relatives with diabetes. And so when I first started this work, I wasn't really concerned about doing it myself because I wasn't. My fasting glucose is fine, you know, all this kind of stuff. And then when I started to make the connection with the gut microbiome and the acetate, which was about 2015, 2016, you know, I started really seriously thinking, okay, if there's such a thing as a gut brain effect, okay, then this is like something everybody should be doing. And so I did studies and I published them and we have seen improvements in cognitive function with the vinegar. And I keep seeing it. And as far as I know, I'm the only one publishing. I can't find anyone else who has looked at like depression, cognitive function. But I have to tell you, I started the vinegar.

[00:25:43] Rob Howe: That was one of your more recently published studies is on the effect of vinegar and depression. So you're seeing that connection between the whatever that's the gut and the brain or blood brain barrier or whatever is generally spoken upon. So that prompted you then to start to

[00:26:00] Carol Johnston: do your own protocol. And I'm like, okay, I'll do it. I can do it. And I have to say for your audience, anyone out there, we have applied metabolomics to our trials. And so metabolomics is a very sophisticated tool to look at metabolic pathways. And I don't want to get any more complicated than that, but the metabolomics is supporting this. In other words, it's showing us the pathways that are upregulated by the acetic acid, by the acetate. And so not only do we have testing like what a psychologist might do. Like if I wanted to measure your depressive state, there's measures you complete that are highly validated and used for years in the psychiatric realm. So we have seen those improvements, but now we have the metabolomics, which is blood metabolites that support pathways that suggest improvements in brain health. And so that's pretty strong. And so what I do, I'm a vegetarian. Okay. So, so I eat out of a bowl. I eat a lot of veggies and, um, and, um, I, I just pour it on top of my veggies. I don't drink it or anything. I just pour it on top of my veggies because at this point, I'm not worried about interfering with digestion. I'm just worried about getting the acetate into my bloodstream. So it can go to the brain. So as a diet, as a, as a person with diabetes, you probably want to think about, I need to do it at the start of the meal because that'll help. But if you are doing it for brain health, you just want to get it in the system. That's really interesting. I think something

[00:27:36] Rob Howe: that you touched on as well earlier is like the aspiration and some of the, you know, which is, I think like if you're, maybe this is an example I thought of is if you're drinking it out of like apple cider vinegar out of the bottle and then you have like a burp afterwards or something, and then you breathe that in, that's the primary, I think, risk of aspirating the vinegar. So you want to try to avoid that if at all possible. Yes. And so that's mixing it with the water. But then I was thinking, somebody who maybe is just like not a vinegar person doesn't really love it, but they can do a vinaigrette on a salad. And would that have a similar or the same effect?

[00:28:11] Carol Johnston: Yes, it would. Of course. Ideally, you would have this pre-meal salad and you would want to make your own vinaigrette dressing because the vinaigrette dressings are highly processed. They have a zillion chemicals in them. As you know, if you've ever looked at the label of a dressing. And so just make it yourself. Because when the commercially purchased vinaigrette dressings are usually two-part oil, one-part vinegar. And you want to flip that. You want to have it two parts vinegar to one part olive oil, let's say. And then you can put in whatever seasonings. You know, you can Google it. There's so many different kinds of vinaigrette dressings you can make. But what you want to change in those recipes is you want it to be two parts vinegar and one part oil because you want to get one to two tablespoons of vinegar in your system. And the other thing I just want to tell people, if you're putting it on a salad, you're going to have to.

[00:29:03] Rob Howe: Right. At the end of the salad, you're going to.

[00:29:05] Carol Johnston: You have to make sure that you get all the dressing in the system. Whatever goes at the bottom of the bowl, you need to maybe take a piece of bread and get it out and ingest it.

[00:29:14] Rob Howe: But that would still be appropriate for getting it into your system. You could still dip it in a piece of bread and go from there.

[00:29:19] Carol Johnston: Well, I mean, vinegar is global. It is in every cuisine around the world. This is a beauty of vinegar. You know, people can even make it if they're so motivated, they can make their own vinegar. But it's in every cuisine worldwide. You know, you go to the Mediterranean, they have their vinaigrette dressings. You go to Asia, they have their rice vinegars that they just drink. They have been doing this in the Asian communities for centuries, just drinking rice vinegars. And then you come to the U.S. and we have apple cider vinegar because we have lots of apples. It's grapes in the Mediterranean. It's rice in the Asian countries. And even Hippocrates talked about the health benefits of vinegar. I mean, we've known intuitively or whatever, cultures have known that this is a medicinal product. And so it's just very interesting. It is. It is a news for diet. I can't tell you how many people, when I published that first article, I would have these emails coming in from who knows where. And they were saying, my grandmother always had vinegar tea in the morning. It's like it's a custom that has come down through generations. And there's a lot of evidence that people were doing vinegar for diabetes in the 1800s.

[00:30:26] Rob Howe: Well, and you had mentioned, too, like there's different applications. It's not all just mealtime. I think you had another study about morning glucose, like whether vinegar before bed would help your fasting glucose in the morning. And it seemed like that that was proven as well. I know that many people with diabetes struggle with feet on the floor syndrome. And as their cortisol and hormones wake them up in the morning, so does their glucose. And so like a morning tea or an evening tea with some vinegar in it seems to be like a home remedy that really works.

[00:30:53] Carol Johnston: Yes. It's fascinating to hear the folklore. And, you know, this is one thing that I was scared about because vinegar cures everything. You know, if you go online, it'll cure warts. It'll cure heartburn. It does everything. And then you can clean your floors with it. You know, it's just like it's sort of like too much. And that's why I was so nervous in the beginning, thinking people were just going to, you know, laugh this off, that this is this is totally unprofessional kind of thing.

[00:31:21] Rob Howe: Well, it is fascinating. Things that are interesting to me are like things that are good for us have been good for us all along. And we just forget or, you know, as regimes change or the years go on, we rediscover things. And oftentimes the most things that are best for us we've known and are documented back to the Egyptians. You know, they're just in hieroglyphs and we've forgotten about them. And, you know, like you said today, so much of our food is preserved differently than it was 100 years ago when we would probably have eaten so many more pickled or preserved things with vinegar before refrigeration, before mass distribution of food to where now we're sort of at a deficit of these good, you know, gut biome is now, you know, a real issue because we don't have those same locally stored preservatives in our homes like we would 100%.

[00:32:09] Carol Johnston: 150 years ago. That is so true. And, you know, it doesn't matter what kind of vinegar it is, because this is another question that people always ask, well, which vinegar should I use? And it doesn't matter because all vinegars, in fact, because vinegar can be poisonous because of the acid, there's regulations on how you produce vinegar and what you can market. The acidity has to be highly controlled because the fermentation process, you can make it much more acidic, you know, depending on the fermentation process. And so there's a lot of regulations on vinegar suppliers and manufacturers on how they produce it. But the fermentation process is the same. It's all the same and you produce acetic acid. So it doesn't matter which vinegar you use. It doesn't matter if it was fermented old school or are the new way, you know, they fast ferment it now. And so they make the vinegars very, very rapidly by fast fermentation methods. Whereas the The old methods were very slow methods, but it doesn't matter. You get the acetic acid.

[00:33:09] Rob Howe: Yeah, there's no benefit from the older, more traditional versus the modern production methods.

[00:33:14] Carol Johnston: You can use white distilled vinegar. It'll work.

[00:33:17] Rob Howe: Yeah, that's so fascinating. You know, I think because, again, like it's something that's so readily available, cost effective. It's in every kitchen. You know, it might be in your garage, you know, like for whatever reason. Right. So I do want to touch on one thing because I know you had mentioned this in our first email correspondences, and I believe that this has been at least sort of debunked with some of the safety concerns for people with diabetes. Obviously, you want to make sure you're monitoring your glucose carefully as this could cause your glucose to go into hypoglycemia, but also there were some gastroparesis and gastric emptying concerns early on. Do you want to speak a little

[00:33:51] Carol Johnston: bit to that? This is interesting. I really didn't understand much about the gastric slowing until I talked to the colleague who's a type 1 diabetic and is having issues right now with this. And then I started to understand, you know, this can be really serious for some people. Early on, people were trying to understand how the vinegar, the mechanism for this anti-glycemic effect. And I already explained to you the digestion. Like it appears to be blocking some of the starch digestion. And I'm pretty convinced that this is a mechanism. Gastric slowing has been shown by some studies, but not all studies. And so, again, it could be the population they're studying. But that effect is not as robust as a digestion effect. But if people have already been told they have issues with stomach emptying, they probably need to be very careful if they want to start the vinegar routine. You know, I don't know, as maybe you know, does a doctor talk to you about this as a patient? Do they do measurements? Is it something that is commonly done so you know?

[00:35:02] Rob Howe: I think it's really like everything depends on your provider. It depends on the symptoms. I think if patients are self-reporting symptoms, I know gastroparesis, because of the damage that living with diabetes does to the microalbumin, your stomach is full of so many blood vessels that they often are among the first microblood vessels to be damaged, along with the eyes and fingertips and feet, when you typically see retinopathy or diabetic retinopathy. And so diabetic gastroparesis is a very common sort of first wave of diabetic complications. In many cases, it's just so variant person to person. You may have a really great in-range A1C, but just because of managing the highs and lows over the years, that you've experienced nerve damage that somebody else maybe has not, even if they have what we would consider worse A1C outcomes. So diabetic gastroparesis is a common complication to living with type 1 diabetes. And so I think that's something where, you know, when we're recommending this, like if you have a history of complications like diabetic gastroparesis or think you have something, best to talk to your doctor. But yes, it is, I guess, to answer your question, it is common and you would have that discussion if you were having the symptoms, which can be pretty uncomfortable for someone living with

[00:36:18] Carol Johnston: gastroparesis. And like I said, not all studies that have looked for stomach emptying parameters have seen issues with vinegar, but some studies have. I feel that the main mechanism is this interference with digestion. And the reason I say this is because if you consume glucola, okay, glucola is already digested. It's just free glucose. It's going to go right into the bloodstream. And if you take vinegar with glucola, nothing happens. The vinegar doesn't do a thing.

[00:36:47] Rob Howe: In fact, if you, I don't know. Wait, so did you say the glucola doesn't do a thing or the vinegar

[00:36:53] Carol Johnston: doesn't do a thing? The vinegar doesn't block that surge. Okay. Because it's already dry dusted. Right. And so if it was actually, if the mechanism was gastric slowing, you know, the slowing of gastric emptying, you would expect to see some effect even with glucola. But you don't you don't see any effect with glucola. And it's really interesting because the meta-analyses, and I don't know if you know what a meta-analyses is, but it's when a statistician takes all the articles that are available on a topic and they put it together and do the analysis to demonstrate the strength of the effect. The meta-analyses for vinegar and postprandial attenuation of the post-parenual glucose is almost 100%, which is unheard of with meta-analyses. You always have studies that don't show an effect. The studies that don't show an effect, there's a couple out there. And you can see these on the meta-analyses because everything's on the favor vinegar side. And then you have these little two dots over here. These outliers. If you went and looked at them, they use glucola. I mean, I just want to say, this is really doing a big disservice because people, doctors will say, oh, there's no effect. I can show you an article. And I'm like, well, that article used glucola, which no one drinks glucola for meals. They eat bread and pasta and pizza, and that's where you're going to get the starch. And so I don't think the audience is really worried about that because nobody drinks glucola for meals.

[00:38:24] Rob Howe: Yeah, not an apples-to-apples comparison. Well, Dr. Johnston, I do want to talk before we wrap up is where you think the research is headed. Obviously, you've been working on this for so much of your career. We're still breaking new ground. It's still showing to have all of these effects, like you said, sort of a panacea of positive outcomes. Where is the research headed and what are you and your team kind of working on today?

[00:38:47] Carol Johnston: So I really think it's this gut microbiome connection. I published in 2004. And then the gut microbiome and its understanding of the importance of acetic acid came 10 years, maybe 15 years later. And now you're reading, I'm reading reports in the literature about the importance of acetate in health. And these are done by, you know, major investigators who understand metabolism, you know, way more than I do. You know, they do all this in vitro stuff and they do all these animal rodent studies and they can get the mechanism. They can take the tissues out and do all this. And they're just saying how important acetate is. These were published like in the last year or two. But none of them talk about the vinegar, which to me, I just like, come on, we need to make this connection. So 7% of your energy production is acetate. Acetate is responsible for about 7% of energy metabolism. It drives metabolism. It drives mitochondria. And again, the mitochondria are in all of our cells, and that's what produces the energy.

[00:39:57] Rob Howe: The powerhouse of the cell.

[00:39:59] Carol Johnston: Powerhouse of the cell. And this effect of acetic acid and the reason the gut is getting so much attention is because that's where the acetate can come from. Vinegar is exogenous. You can consume it. You don't have to rely on the gut, although we want to eat fiber and we want our gut microbiome to be really healthy. But you can supplement that with the vinegar. And I just I really hope that this connection is made because I think this is really, really important. And so you can either make the acid from the gut, which is a much lower amount than you're going to get if you just had a couple tablespoons of vinegar during the day. And so I hope that that connection is made.

[00:40:43] Rob Howe: Well, it does seem like the Venn diagram is vinegar. There's all these different, you know, whether it's acetate or whatever the case may be, like at the center of it all is vinegar.

[00:40:54] Carol Johnston: Right. And it's just so fascinating that acetate is getting so much recognition right now, but nobody is recognizing vinegar as a, you know, and you don't want to say supplement that because vinegar is a food ingredient. It's in our cuisine. We just need to be more, more like focused on making sure that we have acetate or vinegar in our meals every day, you know, in all the meals. and addressing, you know, even eating pickles. You can eat a big dill pickle. I mean, you have to watch the sodium. I mean, there's all these things you need to be careful of because when, you know, if you pickle with a lot of sodium, you're going to get, and that might not be good for blood pressure. But you can pickle at home. You can pickle anything at home. Pickle done.

[00:41:34] Rob Howe: I made my own sauerkraut last year. It's surprisingly easy. It's very simple. Yes. I went on at the beginning of 2025. I had been taking a morning green supplement for a number of years. And I was doing research and reading like of what actually was making it into my body that it was supposed to be coming from the supplement. And was there a way that I could get more or better benefits from natural foods? And what came back was if I just had a teaspoon of sauerkraut every day, I would get much more. And I looked at the cost of that, the actual cost benefit of that. And it was like, you know, 800 percent less cost per month to just eat the sauerkraut. And so, yeah, I went through that. And, you know, I'm a person, I'm on record. I do not love pickled things. They're not like my typical like flavor profile. But now I love my sauerkraut because I've seen the benefits of it. I know that, you know, whether it's, you know, some of the sodium, which is good sodium too for hydration and the fiber and the acetate, you know, I can also, I've learned it's not a big deal for me to drink some dissolved vinegar in water along with my meal. That doesn't really bother me. So another benefit of getting to talk to you today is like, yeah, I have experienced already the lowering of that glucose excursion and seeing how impactful that can be. And you're talking about energy, what everybody wants, right? What every supplement is promising is more energy, sustained energy, no crash. And it seems like right in front of us is this sort of age-old ingredient that can help us out.

[00:43:06] Carol Johnston: You know, I'm a big sauerkraut fan too myself. I'll say. But one of the early emails I got was from a guy in Alabama. He was a coach. And, you know, they have been athletes in the South where it's very humid and you sweat a lot. Yeah. They often drink pickle juice.

[00:43:24] Rob Howe: Pickle juice. Yep.

[00:43:25] Carol Johnston: Have you heard that?

[00:43:26] Rob Howe: I have, yeah. In my high school. So a common thing at two-a-days, two-a-day football in August in Texas or Alabama or otherwise in the South, you know, there are people who die every year from dehydration or sickle cell anemia is triggered by this overheating as well. And so people would be cramping. They would be walking around school because they had two football practices and they'd be cramping. So they would have their water jugs filled like half with pickle juice and half water to get that extra sodium content and get, at the same time, acetate.

[00:44:00] Carol Johnston: Well, unknowingly, they get the acetate, which benefits muscle because the energy, it enhances energy production in the muscle, which is going to be a big advantage for an athlete. And it actually helps you store more glycogen, which is another big advantage.

[00:44:17] Rob Howe: You put me on this. I'm an athlete. I was a professional athlete, and now I just love sports, and I love to play, and I love to move. And so it's still a big part of my life. I'm my best self when I'm working out, and I've got my routine. But you said something really interesting earlier about how vinegar can increase the amount of glucose that your muscles can absorb. And so, you know, for me, when I start to do it, I love playing basketball. So my adrenaline, my cortisol, my insulin resistance at the very beginning gets built up because I'm energized. I'm excited. So I'm going to start a little mixing a little bit of vinegar into my pre-workout because, you know, help minimize that glucose excursion that I get when I get a little bit over. I get a little bit overexcited. I get a little bit angry sometimes. So I get going.

[00:45:04] Carol Johnston: They have done studies in rodents. These studies are done in rodents because, you know, they can excise all these tissues and do all these analyses. But they have seen energized muscle. They call it mitochondrial biogenesis. The mitochondria are activated, which is how you produce the ATP for muscle contraction. But they also see a higher glycogen, which is like for recovery.

[00:45:28] Rob Howe: Yeah.

[00:45:28] Carol Johnston: And so I do think that, you know, that's a whole other area of research that's unstudied as far as vinegar goes. Other than these coaches who have relied on pickle juice, which they have always thought of it as, you know, replenish your electrolytes. Right. Because there are, you know, potassium and sodium in pickle juice, you know, but there's also a ton of acetate, acetic acid.

[00:45:53] Rob Howe: It's so interesting. And like you said, the attribution to what's helping, maybe not even being 100% right. It's also, I think, just like an old wives' tale, which are sort of, I think, becoming more extinct. Maybe it's like the internet has contributed that type of knowledge share in a different way than our ancestors got it. It's one of those sort of Southern things that it's just a byproduct of playing football in the heat. You know that there's going to be a jug of pickle juice out of practice. And if you're cramping or you're feeling really down, that's what you need to use.

[00:46:25] Carol Johnston: So being from Texas, have you ever heard of a pickle sickle?

[00:46:28] Rob Howe: No, the pickle sickle. Oh, yeah. No, I have. I have. OK, but I've never called it that.

[00:46:32] Carol Johnston: It's a popsicle with pickle juice. Yeah, and they freeze the pickle juice and then you eat it like an otter pot.

[00:46:38] Rob Howe: Yep, I've seen it.

[00:46:39] Carol Johnston: Some guy sent me, he said, I want you to test these pickle sickles. Seriously, he sent me these cases and we did a study. We never published it because, again, you know. But we did see the same benefit of eating these pickle sickles as you would if you took the vinegar. So a pickle sickle might be a way that some people can tolerate it better because it's a little bit tastier. I mean, it tastes like vinegar. There's no question. but it might be in a form that people can find more acceptable. They just took pickle juice and froze it and put it in a popsicle thing.

[00:47:16] Rob Howe: Well, and now there are even, I know you held up your shot of apple cider vinegar, but they now have like pickle juice shots in a similar way, like the old five-hour energy kind of looking things, and they're just shots of pickle juice. So it's, again, probably acetate in those that, again, is being marketed as electrolytes.

[00:47:35] Carol Johnston: Yes. And I'll add, too, it doesn't have to be, it can be other things like mustard. You know, there's things that people don't think of as vinegar, but mustard is made from vinegar. And we actually did a study, again, this wasn't published because it was an honor student thesis, but we put on bagels, we put a bunch of mustard and we got the same effect. And so if you're eating a Subway sandwich, just put a lot of mustard on it because that might be more acceptable to some people. But we saw the same benefit of a bagel with mustard on it than we saw with a bagel and the, you know, the diluted drink.

[00:48:11] Rob Howe: Wow. Well, and a bagel, I think, is something that many people with diabetes have kind of given over to not even being able to enjoy because they know what's going to come out of it.

[00:48:21] Carol Johnston: I don't even eat bagels because I, you know, you see the spike and you just think, oh, gosh, you know, that's so even as a non-diabetic person, I don't even eat bagels anymore because that stresses your pancreas, you know?

[00:48:33] Rob Howe: Yeah. Well, I mean, you see people who are wearing CGMs who don't have diabetes and like, what are the things that typically spike them? A lot of times it's breakfast foods or foods marketed as breakfast foods. So bagels, English muffins, bowls of cereal and, you know, their sugars come back down relatively quickly, which is great for them. But again, like you said, stressing the body and having to get all that insulin.

[00:48:54] Carol Johnston: And you have to remember that that is all a marketing thing. It's not to say that you're supposed to have cereal for breakfast. Sure. I mean, our ancestors, I mean, they did a very good job 100 years ago marketing cereal for breakfast.

[00:49:07] Rob Howe: They sure did.

[00:49:08] Carol Johnston: Because you have your cereal and your toast and there's no protein. There's no vitamins and minerals other than what the government puts in there. I mean, it's just, yeah, people, you know, people say, well, Carol, what do you have for breakfast? And I say, I have cheese. I eat cheese for breakfast. And they go, cheese for breakfast? And I'm like, I eat cheese for breakfast. I'm a lacto-ovo vegetarian, by the way, not vegan.

[00:49:31] Rob Howe: Well, and, you know, now you think about, like, for me, for example, knowing what a bagel or breakfast sandwich and hash browns or biscuits and gravy or another, you know, high carb, high fat, like breakfast that pancakes, like waffles, you know, all these like very high carb output foods, nothing against them. I love them all. But, you know, no wonder that you have no energy after that. Your body has to expound so much energy just to process those. And so, yeah, no wonder you don't feel your best after or you need a nap

[00:50:04] Carol Johnston: after brunch because your body's completely tapped out. Well, you know, I did those in the 90s. I did all those high protein, low carb diets and I would talk to my participants. You know, they come in to be fed because we had to feed them to make sure they were getting the right amounts of stuff. And I remember sitting down with them and it was towards the end of the study and because they got to know each other because they were coming in and eating together. And they they I sat down with them and they said, you know what we're going to do on Saturday because the study was was coming to an end. We're all going to meet at, you know, IHOP and we're going to have a bunch of pancakes because, you know, I had taken it away from them. Yeah. And this is when I started thinking, you know, these these diets, this too too much of a change. People are never going to adopt it. People crave those foods. They crave them.

[00:50:47] Rob Howe: Well, and, you know, there's something to be said, too. I think there's schools of thought on this that I think have emerged in recent years that are a little bit more sustainable. And this is becoming, at least in the health and wellness population, something that's more discussed rather than the very strict, very restrictive, unsustainable type of lifestyle where it's do something that's going to get you over the long term. You know, and yes, we need to eat better. Yes, we need to eat more fiber. Yes, we need to exercise more. We need to walk more. We need to get our sunlight. We need to drink our water. But as long as we can be mindful and we have the information that we need to make the right decisions and you can over the long period of time zoom out and make many more right decisions than wrong ones from a food perspective, you know, I think that we'll be in better shape. So I love your approach to simple solutions that are sustainable. Yes. That's you're speaking my language. Well, Dr. Johnston, thank you so much for taking the time today. What a great discussion. I really, really enjoyed this. And thank you for being so proactive in scheduling this. I know you mentioned earlier that you guys are doing the research and let the social media people like us spread the word. So I imagine that you probably don't have much to plug on the show, but I just wanted to thank you for all the work that you and your team have done. And we'll link to all the studies as well. And I look forward to seeing what you and your team continue to do from here.

[00:52:06] Carol Johnston: All right. Well, hopefully, hopefully we can continue to show all these good effects. You bet. It was a pleasure. It was a pleasure to talk with you.

[00:52:12] Rob Howe: Thanks so much.