Is Your Mouthwash Killing Your Microbiome? – with Dr. Kourosh Maddahi


With all the different oral care products easily available to most people, keeping your mouth clean and cavity-free should be easier than ever before! But what if our regular oral care routines are hurting us just as much as they are helping us? Are we destroying the good bacteria with the bad bacteria? In today’s episode, we are exploring oral hygiene, the toxins in your mouthwash, fluoride, dentists, protecting your microbiome, and more!


We answer these questions:

– What have we been missing about oral care?

– What is the connection between mouth bacteria and the microbiome?

– What are the ingredients and chemicals in mouthwash to avoid?

– How should our regular oral care routines change?

– How should we approach fluoride?

– How should we approach mercury fillings?

– How can you find a good dentist in your area?

– And more!


Still want to learn more? Schedule with Dr. Barter today!


Connect with Dr. Kourosh Maddahi:







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About Dr. Maddahi:

Dr. Kourosh Maddahi is on a mission to dispel long-held oral hygiene myths that are hurting our body’s microbiome and our overall health.

A respected U.S. medical author and practicing cosmetic dentist, Dr. Maddahi was taught in dental school that a germ-free mouth is a healthy mouth, and that killing germs—bacteria—is always a good thing.  It’s the same message that’s been hammered into our brains all our lives from marketers whose products promise to “kill 99% of germs!”  However, the damage we’re doing with our antibacterial toothpastes and mouthwashes is being felt all over our bodies— and study after study now proves that our daily oral hygiene routines are significantly damaging our whole-body health.

Dr. Maddahi has closely followed, and even contributed to, the breakthrough science that’s finally being done in oral care.  His latest book, The Toxic Overload, dispels the myths.  And he’s also developed a line of effective oral care products that don’t harm the microbiome, called Lumineux Oral Essentials. 

His goal is to completely change the way we practice oral care, basing it on modern science, not marketing slogans. 

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Dr. Ann-Marie Barter is a Functional Medicine and Chiropractic Doctor at Alternative Family Medicine & Chiropractic. She is the clinic founder of Alternative Family Medicine & Chiropractic that has two offices: one in Longmont and one in Denver. They treat an array of health conditions overlooked or under-treated by conventional medicine, called the “grey zone”.



Dr. Kourosh Maddahi [00:00:00] So we start to look into this whole idea of bacteria, and we find out that more than 98 percent of the bacteria in your mouth. They’re healthy and protective bacteria, and this whole concept of microbiome, which you’re very much familiar with, comes into play.

Intro [00:00:20] Are you struggling with bloating, gas constipation and fatigue, but don’t know what’s causing these problems? The Gut Health Reset podcast with Dr. Anne-Marie Barter dives deep into the root causes behind these issues that start in the gut. This podcast will give you the knowledge you need to heal your gut and reset your health.

Dr. Ann Marie Barter [00:00:42] Today on the Gut Health podcast, we are discussing how oral care is directly linked to your gut health, how a lot of the products that we use and that are on store shelves are actually toxic for your body and can be harming your gut health. How some of the things that you’re eating or your dishwashing detergent could also be contributing to your gut health issues and how our brush floss mouthwash routine may actually be harming your overall health. My name is Dr. Ann Marie Barter, and thank you so much for being with us here today. We are so grateful to have you, and today my special guest is Dr. Maddahi. He is on a mission to dispel long held oral hygiene myths that are actually hurting our body’s microbiome and our overall health. He is a respected U.S. medical author and practicing cosmetic dentist. He was taught in dental school that a germ free mouth is a healthy mouth and that killing germs bacteria is always a good thing. It’s the same message that’s been hammered into our brains, all our lives from marketers whose products promise to kill ninety nine percent of germs. However, the damage that we’re doing with our antibacterial toothpaste and mouthwash is actually being felt all over our bodies. Study after study now proves that our daily oral hygiene routines are significantly damaging our whole body health. Dr. Maddahi has closely followed and even contributed to breakthrough science. It’s finally being done in oral care. His latest book, The Toxic Overload, dispels these myths. He’s also developed a line of effective oral care products that don’t harm the microbiota called Lumen X. Oral Essentials Dr. Maddahi, it is such a pleasure to have you here on the podcast today. So thank you so much for being here today. I’m so excited to dove in

Dr. Kourosh Maddahi [00:02:51] I’m excited to be here. Thank you very much for the invitation. I really appreciate it.

Dr. Ann Marie Barter [00:02:56] Absolutely! So, you have some interesting things to say about traditional oral care, and that might be counterintuitive to what we have learned in the past. Can you dove into that a little bit?

Dr. Kourosh Maddahi [00:03:15] Yeah. So I mean, since my background is in dentistry and I’ve been intense you for 35 years, I in the past I would say 15, 20 years, I’ve been very much interested in seeing exactly how did we ever survive from the caves? How did our body protect us? And we didn’t have any modern medicine. We didn’t have any toothpaste, mouthwash, any of these things. What was it about our body that helped us? Survive. So what’s interesting is that when you look in the world of oral care, dentistry, dentistry and it related in the past 70 years, the entirety of focus has been on killing bacteria. And when you look as to why is because bacteria causes gum disease, bacteria causes cavities, bacteria causes bad breath. So what should we do? We should kill the bacteria. But the main issue is that if that was the solution, then people should not have cavities. People should not have gum disease. People should not have bad breath. But that’s not the case. We see that gum disease in the form of gingivitis initially into bone and gum recession, which is periodontitis, is happening at an earlier age than ever before. So there is something going on that doesn’t make any sense. So we start to look into this whole idea of bacteria, and we find out that more than 98 percent of the bacteria in your mouth. They’re healthy and protective bacteria, and this whole concept of microbiome, which you’re very much familiar with, comes into play. So microbiome is a network of microorganisms that has good bacteria, bad bacteria, viruses, all sorts of things, but predominantly is good bacteria and it’s protecting us. And how is it protecting us? First of all, by the amount of real estate it takes in the mouth is protecting us, and that real estate doesn’t let other bacteria, other viruses to come in here and grow. And the second part is because there is bad bacteria in the microbiome at a very low levels. It helps with the help of your immune system to produce antibodies against those very low level bad bacteria so that you don’t get sick. So that’s the symbiotic relationship between microbiome and the immune system. But the microbiome itself is our first line of defense, and I often tell people, why aren’t we getting eye infection more often? Why are we getting ear infection more often? And this microbiome coating is there to protect us the same way that is in their mouth. So now when you start to look into oral care, you see not only they are proud of killing bacteria, and they’re also advertising everywhere that because 99 percent of the germs, which is the bacteria that’s in our mouth. So the whole idea of oral products is how do we destroy the microbiome? And this destruction of the microbiome then has produced other problems, so that’s where the frustration came from for me is that I wasn’t getting this exact. Results that I was looking for for my own patients, I wasn’t getting rid of this information and some other things that were going on in the house. And as I looked into the ingredients more and more, I saw that not only do some of these ingredients are not good, they’re actually toxic. But because we look at toxicity in a very short term studies and anything that doesn’t really kill you or harm you that much, it’s okay to put in your body. And when I go back to dental school. A lot of these mouthwash is in toothpaste and everything we’re referred to as chemotherapeutic agents, so it was known that there is a bit of destruction of your healthy cells. But as long as you are getting rid of the bad bacteria, it was OK along with the good bacteria. So this concept of bad bacteria that causes cavities and gum disease also has another dimension, and that other dimension is that if you kill bad bacteria because there are sort of gram negative types of bacteria within their cell wall, there is toxins. So there’s an endotoxin. So when you kill them, there’s toxins that are released. And if you don’t kill them, there are toxins that are released that causes the gum recession bomb, recession and cavities. So you’re damned if you do, you’re damned if you don’t. So what was the ultimate solution, the ultimate solution is come to it actually came from a landmark study by done by one of my close friends, Dr. Ngozi, which did a study on homeless kids in Manila. Now. There is a type of bacteria called a bacteria. That in effect, about one and a half billion people in the world. You definitely see a prevalence of it in Asia and China, in the Middle East and South America, Central America. And there is more and more of it that I’m seeing, even in my own practice. And the characteristic of this particular type of bacteria is that it destroys the gum and the bone around the four upper teeth for lower teeth and the back molars. And these and it also strikes at a very, very early age. So these homeless kids all had this bacteria and they were suffering from this particular gum disease. And what he asked them to do is to rub sea salt under gum twice a day. And he followed these kids, along with the French scientists, for 10 years. That’s what makes it such a landmark study. And what he found was astonishing because at the end of 10 years, the gum disease had not progressed. There wasn’t really any more gum disease yet the bacteria was still alive. So the whole theory that you have to get rid of the bacteria in order to get rid of the disease, it is not true. What is it then about the bacteria is the toxin. So if there is a way to neutralize the toxins of the bacteria, then you’re able not to kill them so that you don’t get the production of the of toxins in your mouth. But at the same time, you’re getting rid of all of the harmful effects of it. And that’s why I have such a problem with what’s out there today and what’s out there today is. Toxic ingredients, different coloring dyes in the mouthwash and all sorts of chemicals and antibacterial activity. And then the second part is that the destruction of this microbiome in the care products leads to more viral load, leads to more issues and problems overall. And since you are so knowledgeable in the area of gut health, talking about the first point of digestion is your mouth and the food that you put in your mouth and the things that you consume in your mouth. And and it is all connected also with your gut, but also with the rest of your body. So there are multiple ways that what you put in your mouth gets into your body. One is that you swallow it. It’s fine that we know, but also rate of absorption of anything you put in your mouth into your body is very, very high. So there was a study that we had done along with the UC Irvine, that we had people rinse their mouth with Listerine and after 60 seconds of brisk rinsing and spitting out. We measured the amount of alcohol because there’s a particular type of alcohol in this industry and to die in your bloodstream after 60 seconds. We found traces of the alcohol and died. And after five minutes, there was even more die in the body. So the concept that you’re just rinsing and throwing out does not mean there is no rate of absorption. So that’s another way that what you put in your mouth the same way when somebody is having a heart attack, you tell them to put nitroglycerin pills under your tongue is because the rate of absorption into your bloodstream is even higher than if you swallow them. So this is the whole central idea of what is wrong today with the oral care products that are out there.

Dr. Ann Marie Barter [00:12:48] So when you talk about the oral care products that are out there and caustic agents in the oral care products, can you give specific examples of what those are? Because we’ve kind of talked a little bit around it. So let’s just drill down into some specifics to that.

Dr. Kourosh Maddahi [00:13:05] So I think number one is alcohol. So the alcohol makes it antiseptic, right? And alcohol, that whole idea of this burning sensation that you have in your mouth thinking that it is doing something what alcohol is doing is, first of all, killing everything that’s in your mouth, good and bad. So alcohol is a key part, a key component. There were ingredients such as triclosan in Colgate, which is another antibacterial type of things. And then along with these is also the whole concept of the different chemical, sodium sulfates and all these other things that are there to make toothpaste foam. But it’s the same agent that is used in car washes for foaming agents again and sort of the destructive effects on the tissues of the mouth. So there’s a sliding effect of sometimes I see patients that is just peeling off is a lot of the responsibility of that is on the sodium sulfate that’s in the toothpaste. So ingredients such as these. But the simplest one, if you want to really, really simplify it, is just the alcohol that alcohol is destroying everything.

Dr. Ann Marie Barter [00:14:30] So many people struggle with bloating, bowel issues, brain fog, fatigue. You might not even have any gut issues, but did you know the cause of it could be food sensitivities or gut infections? What I have done is I have brought a talented functional nutritionist into my practice. We have very similar training in the nutritional world. And her name is Alexis Appleby. She is awesome. So you can head on over to our website. &Lt. Alti Fam Fam Med Med and have a consultation with her and schedule so that she can help you get to the root cause of your problems. So our our daily routine, you know, we we’ve been told to brush twice a day. We’ve been told to floss and use mouthwash. So and in a lot of people are using traditional kind of toothpaste off the shelf, traditional mouthwash off the shelf. So what is wrong with doing that routine? And do you have a recommendation to change that a little bit?

Dr. Kourosh Maddahi [00:15:40] Yeah, I mean, so the problem with the routine is the antibacterial activity and the toxicity that’s within it. And if we look at toxicity not as a short term, but as a cumulative problem that your body accumulates this toxicity over time, we start to look at things in a very different light. So is there a way that you can have a product that is first of all, certified nontoxic and then on top of it, it doesn’t kill any of the bacteria, and that’s what led me to create a company called Luminal Essentials. And what we started to do based on some of the research that Dr. In was that he had done and others is we came up with the ingredients that are certified nontoxic. So we knew that there was a non toxic effect. We found ways that definitely there is no alcohol and there’s no real chemical that kills any bacteria. We provided that type of study. So one of the key things is not only the traditional oral care products have not given us the proper solution, but then natural products haven’t been effective at all. And there are no real studies behind the natural products. So, so you’re looking for ultimately in anything you eat or anything you consume is you’re looking for something that’s safe but effective. That’s what you’re looking for. The holy grail is that area right and safe, meaning the non toxicity. So it’s not killing any healthy cells. Effectiveness is what is it doing in terms of your oral health? Right? And this area was where we concentrated and we did a lot of research on and this is why we came up with a toothpaste, mouthwash and particular type of a toothbrush that doesn’t really destroy your gums made of castor oil bristles. That is very sort of a bendable pliable. But at the same time, it cleans properly and also full whitening lines because of whitening has peroxide as a main ingredient. And this peroxide also not only destroys the microbiome, but more importantly, it causes tooth sensitivity, gum irritation, and the tooth sensitivity comes from etching of the enamel because it’s an oxidizing agent. But that’s the only FDA approved ingredient for whitening. So instead, we started to use ingredients such as. Coconut oil, sage or lemon peel oil as a whitening agent and our main signature ingredient in these products is that sea salt. And the reason for that sea salt is the amount of mineral content that is in the Dead Sea salt. So when we’re looking at the different salts, that table salt has two percent mineral sodium chloride. We look at the sea salt is about 20 percent minerals. Himalayan salt is about 40 percent minerals, and that sea salt is about 86 percent minerals. And these minerals are very key in terms of the benefits that they provide in some aspects strengthening of the teeth in terms of the minerals that contained within the Dead Sea salt. And as a whole, it’s not the whole effect that it’s just not destroying this microbiome. So these are the kind of things that we talked about. And then we started to look into different types of toothpaste and different types of mouthwash for different conditions. So if you take the entirety of the population, you can categorize and in one of four categories. So people are looking for government to sell. Another category is people that are having sensitivity in their life, they want to reduce the sensitivity of their teeth and their roots sensitivity, and then there’s another category I want whiter teeth. And then there’s a category that want to get rid of the symptoms of dry mouth due to either mouth breeding allergies or taking medications that causes dry mouth. So we have created this full line of oral care that addresses each of these categories. And again, based on oils that are in it and their main oils, clove basil and then mince that plus that sea salt organic aloe vera olive are reduced as a soothing agent is underneath all of it. And then we add layers of other oils for whitening, for dry mouth and then for sense of smell.

Dr. Ann Marie Barter [00:20:41] One ingredient I didn’t hear you mention, which I think is going to be the question on everybody’s mind is fluoride. What’s your take on fluoride and where does that fall?

Dr. Kourosh Maddahi [00:20:56] OK. Yeah. So it’s a very good question, and as a dentist, we have been programed to understand the importance of fluoride in terms of strengthening of the teeth. Now the question is, does fluoride make your teeth stronger? Absolutely. There’s no question about it. But fluoride is also a neurotoxin. These are where we’ve got the controversy around fluoride and then because fluoride is also in the water. All of our food sources is also has some level of fluoride in it, so when you’re eating a potato broccoli, even when you eat cereal, there’s fluoride in action. So we what we did was we did not put any fluoride in any of our products. We understand the number one, you are consuming a lot of fluoride. And one of the things that was very striking was that when you go on the CDC website, you’re looking at fluorosis. That means there’s too much fluoride and they’re talking about similar, which is what happens is that you get these white spots on the teeth, sometimes yellowing of the teeth, but also a yellowing of all the bones in the body and making it more brittle. So this process is coming as a result of everything containing fluoride, so we don’t want to add more fluoride to it. And then I go back to the mineral content of the Dead Sea salt using and other types of mineral to strengthen the teeth. So that is our sense. So that’s why we did not put any type of fluoride in our toothpaste mouthwashes or anything like that.

Dr. Ann Marie Barter [00:22:40] So if if the science is so clear, you know, you can utilize, you know, you have created a natural product that is highly effective. Why are all of these cosmetic products still on the market and why hasn’t the research fully kept up? Because I hear fluoride fluoride fluoride, you know, across the board, and that’s probably one of the number one questions I get is about toothpaste.

Dr. Kourosh Maddahi [00:23:08] Right? So I tell you that we take care. Type of a restoration called amalgam, which has silver and mercury in it, right? It is a banned substance in many of the countries all over Europe, Switzerland, Germany, Italy, Tucson. You cannot get an amalgam filling to be put in your tooth. There has been multiple studies that shows that the mercury leaks from the building that you’re putting in someone’s mouth. The Department of Health and Human Services is very worried about how a dentist is storing excess amalgam pieces, and it has to be under water is a biohazard material. There is more and more worry about how does that mercury go when you are drilling, get in a dental office into the ocean because a lot of the mercury in the ocean is also from the dental offices. How do you trap this mercury so it doesn’t go into the ocean yet? There’s still nine hundred thousand amalgam fillings out of silver and mercury, and it is being placed in the mouth. So if you are in the United States, so if you are looking so as a clear cut answer as to why is there fluoride? I would tell you, boys are mercury wiser. All of these other things that we are so worried about is being placed inside someone’s mouth. You look into is there a special interest, is there something that’s being protected, you know, all of these questions come up. Some of it doesn’t make sense. Certain countries are going away from fluoride. More and more research that’s coming up. That’s saying that there is a lot of controversy around fluoride. But you know, we were smoking for 30 years, 40 years before we got finally this second hand smoke study. We were we were using asbestos in the walls and around the docks in homes until 30, 40 years later, we found out the connection between that and other types of cancers. So that’s why I mean, it doesn’t mean. It’s not harmful. It doesn’t mean there’s not some preliminary research, doesn’t mean it’s not controversial, controversial, but it may take a long time to get to the point that we do away with these types of things. Mm hmm.

Dr. Ann Marie Barter [00:25:49] That’s a really good explanation because I feel like some of dentistry it seems like it’s a little slow to catch up to some of the research. But I mean, that’s every boat kind of turns slow anywhere medically, right? So it’s a it’s a big turn that we have to make it.

Dr. Kourosh Maddahi [00:26:04] Yeah, it is. It is a huge it’s out of both of them, if you can imagine, is a huge type of a ship and any movement in that ship. It’s very slow and and sometimes very much behind what’s out there.

Dr. Ann Marie Barter [00:26:21] Mm hmm. And you’re looking in mouths all day long. And so there has been controversy, controversy on diet and in mouth, in oral health. So what have you seen be the best diet for oral health?

Dr. Kourosh Maddahi [00:26:40] Yeah, so I think we have to and there’s a there’s ways of answering this question, but I think the basic question is that what is it that we’re putting in our mouth that again has harmful effects? So unfortunately, we talk about the fluoride, but everything that we’re consuming that’s not organic is also has pesticides and pesticides are again a form of antibacterial products. So what we are we are trying to do is to sort of get away from things that contain hormones, contain antibiotics in the meat. A lot of the needs that people consume, there’s antibiotic antibiotic again, is another form of thing that what happens in your mouth, what happens in your gut, your hormones, what happens in your mouth, and then more importantly, what happens in your gut and then the pesticide, what’s happening in your mouth or what happens in your gut? So we want to sort of move away from things that contain antibiotic, contain hormones and contain pesticides. So these are broadly and generally, if you start to follow these things, is a better way of actually helping your diet, which is healthier. But more importantly, it’s always a question. I ask people, Do you take antibiotics every day? And everyone says, no, why would I take antibiotics? I don’t have the infection yet. Your laundry detergent, your dishwasher detergent, your cleaning products at home, the hand sanitizers and then the pesticides, alcohol and then all of the antibiotic within the myth. You’re being inundated one way or another with antibiotics on a daily basis. And that’s why certain types of things are continually to increase. And you look at in 1970s and 1950s, when antibiotics came into use, their rates of infectious disease went down. But yet the rate of autoimmune disease started to go up. So we start. We’ve got to really look at these things as to what are we putting in our body and starting with, what are you putting in your mouth that can affect the rest of your body? And there is clear science that shows that whatever is happening in your mouth is clearly affecting so many organs of your body. You know, there is always the connection between gum disease, with heart disease, with diabetes, with early term pregnancies where you’ve got premature babies, Alzheimer, all sorts of things that are going on. So we got to be more careful as to what we’re putting in your mouth. But you can be on a gradient basis and you start to get away from all sorts of things that has actually antibacterial and anti microbial ingredients in it.

Dr. Ann Marie Barter [00:29:37] I think you just make so many great points here. What I’ve seen clinically in practice is if somebody has a gut issue and they have a mouth issue, I can’t fix their gut until their mouth has been resolved. Period end of story. It doesn’t matter how much I negotiate, how perfect their diet is, et cetera. Until whatever is fixed in the mouth, you cannot fix the gut because you’re just constantly swallowing whatever is in there. The infection, whatever is going on, costly and the rest of your microbiome in your gut. So it’s just it’s just an uphill battle. Why don’t more Dennis practice like you? Because I think the the question I’m going to get is where do I find a dentist like that? So why? Where can someone find a dentist like you in their area?

Dr. Kourosh Maddahi [00:30:29] So I think a lot of the agencies, I mean, a lot of the. There are different associations that are dentists part of and they are continually looking at not only the effects of some of our diets, but more importantly, the effects of dental material that are being placed inside your mouth. And what is interesting is that there are tests that people can take that form of a blood test that shows. Reactivity to different dental products and dental materials. When you start to do some of this testing, which I have done over 15 years, we find that there is a lot of different material that people can be reactive to that don’t even know they don’t know it. Because where we we find allergies and hives and some other things, the way that you see the inside the mouth is very different. You see a general rise or a specific localized sort of an inflammation that inflammation doesn’t resolve easily. And then you look more into it that there is a dental restoration on. That’s true. That’s causing that type of inflammation, and we should look into further use that viewpoint. That’s the reactivity. So I think that finding some of these associations, finding some of the doctors that are within these associations is very important for the overall. American Dental Association does not believe in any of these ideas. They do not promote it. They do not accept it. And so on a wider ground in terms of looking at dental schools where the education is taking place, dental hygiene, where the education is taking place, so all the way through the different association within dentistry, you sort of don’t see anything about it and they don’t believe in any of these ideas and they’re not being taught any of these ideas. As a result, finding people that are very much interested and they have committed in their practice to this type of practice is going to be a lot more difficult because what are they going to learn, where they’re going to understand the exact procedures to follow in order to remove a medically filling? So I am a I am a olty, is one of the organizations that are really great. And there’s other things that you do when you search these types of things you find. And that’s the best way that I can recommend in terms of finding dentists that are have this type of a mentality.

Dr. Ann Marie Barter [00:33:20] And where can people find your products if they’re interested?

Dr. Kourosh Maddahi [00:33:26] Yeah. So our products again, is the website. We are also on their brand name is Luminol. And you can find us in Amazon. You can also go on a store locator because we are in Walgreens and Whole Foods, Sprout, Rite Aid and ever expanding Wegmans, ever expanding. We’re in about 10000 different stores. So store locator on our website will help where we are, our website and Amazon marketplaces that people can find our products.

Dr. Ann Marie Barter [00:34:06] Well, thank you so much for being here today. This has just been such a pleasure to learn about this, and I think that this is a question on everybody’s mind. And boy, if gut health and oral health are not just very connected, they certainly are. So anyway, thank you so much for being here today.

Dr. Kourosh Maddahi [00:34:27] Thank you so much. I really appreciate it and thank you for everything you do to educate the public. Really appreciate that.

Dr. Ann Marie Barter [00:34:33] Thank you so much.

Intro [00:34:37] Thank you for listening to the Gut Health Reset podcast. Please make sure you subscribe, leave a rating and a review. More people can hear about the podcast and hey, take a screenshot of this episode and tagged Dr. Ann Marie on Instagram or Facebook at Dr. Ann Marie Barter.

Dr. Ann Marie Barter [00:34:53] And for more resources, just visit Dr. Ann Marie




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