Skip to content.

Episode 3: Biofilms, Digestive Plaque and Your Health

Episode 3: Biofilms, Digestive Plaque and Your Health

In part 3 of the series, Dr. Mahmoud Ghannoum joins Andrea to talk about how the organisms around and in us form biofilms to protect themselves from threats, such as antibiotics and our immune system. In part 1, we covered the basics of the microbiome. In part 2, we discussed fungi. If you haven’t listened to those episode yet, we’d recommend starting there.  

Think of organisms as microscopic animals. To survive, they need a few basic things: food, waste disposal, and security. In today’s episode, we’re talking about how microbiota keep themselves safe using biofilms.

Biofilms act as a Jell-O-like layer that encase bacteria and fungi, allowing them to swiftly deflect attacks. In our guts, biofilms are called digestive plaque and they play a big role in determining our health and disease. For example, when pathogenic or virulent strains of bacteria and fungi set up a biofilm in the intestines, they can begin to break down the delicate lining and gain access to our bloodstream.

On the other hand, when beneficial strains build biofilms along our gut walls, they act as protective mechanisms that can aid in our survival.

On this show, our resident microbiome expert, Dr. Mahmoud Ghannoum, tells us why we’re starting to hear more about biofilms and gives us tips on how to minimize them in our day-to-day lives.


Episode 3 [Biofilms]

Released Dec. 20, 2018

In part 3 of our three part series, Dr. Ghannoum is back talking about biofilms and digestive plaque. An often-overlooked part of health and disease, biofilms exist all around us, and in the body in places such as our mouths and guts. On this episode, Andrea talks to Dr. Ghannoum about what biofilms are, how to deal with them, and whether they’re necessary for health.  

Here’s what you’ll learn in Episode 3:

  • What is biofilm? [2:07]
  • Busting up biofilms [5:48]
  • How do we prevent biofilms [8:11]

BIOHM gut quiz


Andrea Wien: Welcome to the final episode of our three-part introductory series on the microbiome. I'm your host, Andrea Wien, and this is The Microbiome Report powered by BIOHM Health. In episode one, we looked at exactly what constitutes the microbiomes of our bodies. Episode two uncovered the truth on fungus, and episode three is all about biofilms and digestive plaque. Our resident expert and microbiome researcher, Dr. Mahmoud Ghannoum, is back to enlighten us on the power of biofilms. We talk about what they are, why they're such a mystery to people, and whether they can ever be helpful rather than harmful.

If you're liking the show so far, don't forget to subscribe so you never miss an episode. Now let's get to it. We're back in the studio today with Dr. Ghannoum, and as promised, our episode on biofilms is here. I'm so excited. Thank you again for joining us.

Dr. Mahmoud Ghannoum: It's my great pleasure.

Andrea Wien: You mentioned briefly in our episode on fungus a bit about what biofilms are. We didn't have too much time to get into them. So I'm very happy to dedicate this whole session to them. Tell us what biofilms are, how you started researching them, and why they're so important.

Dr. Mahmoud Ghannoum: I am really excited about biofilms, and, I few years ago, again, usually what I do, I go to these meetings, and I don't go to meetings which talk about fungus which is my field. I go and listen to what other people are talking. A few years ago, I went to a meeting, if I remember correctly, in Atlanta, and they were talking about biofilms. It was a new area. Again, I said oh, this could be very interesting because why they were talking about biofilms being a community of organism which come and they start to work together and they form as if they have a city. Within this city, they communicate together, and they are basically have the same services we have in the city. They need food, they need a waste disposal. So that fascinated me. With that, I came back to the lab and I say oh, I really need to look at this biofilms.

Of course, what do I do? I look at Canada, and we start to looking at the biofilm. Let me now tell you what is a biofilm. Biofilms, if you can imagine, you have…let me give you examples also from outside medicine. For example, when you go to a marina, you see all these boats in the marina. What do you see in the outside? You have this layer of algae and the slimy layer. Guess what? These are organisms, whether it's bacteria or fungus, that stick to the side of the hull of the ship, and then they start to produce sort of jello. That's why you see it slimy. This jello as if they are having…it's like you have M&M and you put this M&M inside these jello. So the M&M are the microorganism, and the jello is what they produce to protect them.

Andrea Wien: Going back to the city analogy, it's similar to we need security, and so they're building this as a security around themselves.

Dr. Mahmoud Ghannoum: You are absolutely right. I tell you what security they have. When they live inside these biofilms, if you try to get rid of them with antibiotics, guess what? They are resistant to antibiotics. Not only they have all the services you have in a city, you also have an army to protect them because you cannot have…usually drugs or antibiotics, for example, they will not be able to penetrate or break through this jello, and that's why the organism are happy there and protect it.

Andrea Wien: Can our immune system also not break through that jello?

Dr. Mahmoud Ghannoum: We did a study, and it showed that even our immune system have difficulty in penetrating this jello.

Andrea Wien: Some people use the word digestive plaque. Is that the same thing as a biofilm, or do they differ?

Dr. Mahmoud Ghannoum: It is digestive plaque. It's referring to a biofilm, but in our digestive track, in our gut, for example, and the best example, why we said digestive plaque is that it's like the plaque in our teeth. Every morning we have to brush, and in the evening. Why? To get rid of this plaque. This is actually is a biofilm. This is the best, simplest example of biofilm, but instead of forming in our teeth, it's sticking to our gut line.

Andrea Wien: It is, I would assume, much more difficult. Is it the most difficult in the body to get rid of in terms of biofilms, or are there other biofilms in different places that are just as tough to eradicate?

Dr. Mahmoud Ghannoum: Usually we have biofilms in the vagina. We have biofilm in the gut. We have biofilm in the oral cavity or in the mouth. The other place where you have a biofilm, and it's difficult to get rid of, when people go to hospitals, for example, they put catheters to give them medicine or to give them food like nutrition for babies. What happens, these organisms or bacteria and fungus, they come and stick to the catheter, and they do exactly what they do in the ship where they secrete this jello, and they protect themselves. Because of this in hospital, we call catheter-associated infection, and it is a biofilm. That is very difficult to get rid of.

Andrea Wien: Are there any instances when biofilms are beneficial to us?

Dr. Mahmoud Ghannoum: Yes. Yes. Definitely. Like in the gut, for example. The good organisms, like Lactobacillus, bifidobacterium, they make biofilm, but there is thin biofilm, which is not aggressive biofilm, and that allows them to stick to the gut lining and protect it and also help other organisms. So yes, there are instances where biofilms are good.

Andrea Wien: When we're thinking about busting up biofilms, is there a way in medicine or in supplementation to attack only the biofilms that are hiding the pathogenic bacteria and fungi, or is it we have to attack all biofilm, eradicate the harmful organisms and then replenish?

Dr. Mahmoud Ghannoum: This is really very important question because a lot of people think about it. One of the ways is you need to get probiotics that target the pathogenic organisms. That's why, for example, in BIOHM, we came out and selected rationally which drugs will only inhibit biofilms form by the pathogenic organisms. At the same time, what you are doing by taking this probiotic, you also are replenishing and helping the good organisms. Basically, you are doing two ways.

Andrea Wien: Killing two birds with one stone.

Dr. Mahmoud Ghannoum: That's exactly true.

Andrea Wien: It's interesting to me because the National Institute of Health has publicly said that biofilms account for 80% of microbial infections in the body, yet not many people have heard of them. Why is that?

Dr. Mahmoud Ghannoum: Well, because it's scientific term, biofilm, people don't realize it, but I gave you a good example. People in hospitals, how many plastic material we put in our bodies? You have the catheters. Nowadays, we have knee replacements. We put valves in our hearts. All of this plastic material is a place where organisms can come and stick or adhere. That's why, because we are increasing the use of all of these indwelling catheters, for example, we are giving opportunity for the organisms to come and stick, and then they become resistant to antibacterial agents or antifungal agents, and then it becomes very difficult to get rid of them. That's why they account for such a high percentage of infection.

Andrea Wien: This is why we're also probably hearing more about them because in the past, we didn't have all of these plastics or we didn't have all of these medicines that were allowing them to grow. Now that we're having more of these things, we're having more biofilms, and so we have to pay attention to them.

Dr. Mahmoud Ghannoum: Oh, absolutely. In a way, it's the way we practicing medicine is changing, and we are introducing…we are making people live longer. Because of this, we are having other issues which we didn't have before.

Andrea Wien: Can we prevent biofilms from forming in the first place, or is it just an inevitable part of our symbiosis with our microorganisms?

Dr. Mahmoud Ghannoum: I think there are a lot of efforts and a lot of research have been spent to try to understand how to prevent biofilms. In fact, one of the research which I did is we wanted to prevent biofilms forming on catheter. We were able to develop a drug, which really now is in a phase three clinical trials, where we were able to ... if you put this solution in a catheter for one hour a night, you will prevent the formation of biofilm. There are efforts, and there are other people, obviously. This is a very, very hot area where people trying to find new ways to prevent biofilms, and I really hope we will be successful.

Andrea Wien: This is a little bit of a switching gears, but when we're thinking about something like leaky gut, intestinal, permeability, what role do biofilms, if any, play in that experience?

Dr. Mahmoud Ghannoum: Leaky guy, usually what you say, like organisms in the gut, they gain access to our bloodstream. Biofilms, especially when it is made of pathogenic organism, or organisms that are virulent, the bad ones, for example, what they do when they are forming the biofilm on the gut lining, they start to break down the gut lining and cause injury it. Once you injure it, then you will have leaky gut. Definitely biofilms form by bad organisms are a potential really damage, or they can damage the lining of our gut and therefore allow the organisms to go in and thereby what we call leaky gut.

Andrea Wien: In that same way then, could by good biofilm, one created by Lactobacillus or bifidobacteria, have the opposite effect where it actually is creating a layer of protection for the gut?

Dr. Mahmoud Ghannoum: Yes, it is true. Also you find the ... we published a paper. We found that the bad organisms in the gut, or the virulent one, what they do, they start changing their forms so that they can cause damage as I said. For example, they can secrete some enzymes which break down the lipids that cover our gut and the proteins, and then that will allow the leaky gut.

Now the good organisms, even though they make biofilm to protect you, but they don't have these virulent factor. To make something cause disease, it has to have factors that allow it to do so, and we call it pathogenicity factor or virulence factor. These good organisms don't have that.

Andrea Wien: This might be a bit of a stretch then, but in that same vein, could autoimmune diseases like arthritis, rheumatoid arthritis, actually be caused by bacteria that have escaped the digestive tract and settled in the joints where the immune system is starting to attack it?

Dr. Mahmoud Ghannoum: The best example in this area is in streptococcus. When people develop streptococcus, at the end, you will find a lot of people start to develop arthritis and joint pain. Definitely, there is a correlation between that.

Andrea Wien: You've found that pathogenic bacteria in Crohn's patients can form a partnership with fungi that make this intestinal inflammation worse. Is this a byproduct of biofilms?

Dr. Mahmoud Ghannoum: Yes. In our study, we showed that candida, one of the species of candida called candida tropicalis, works with E. coli, which is a pathogenic bacteria, as well as Serratia marcescens which is another pathogenic bacteria. They work together to form a biofilm and then start causing havoc inside there.

Andrea Wien: Aside from taking a product that busts up the biofilms, what are some good ways to prevent them through your diet and lifestyle? If you do have them, aside from taking a product, what else can you do to ensure that they're not forming?

Dr. Mahmoud Ghannoum: I think what we need to do, as we were talking about, is can we use a dietary approach or nutritional approach to try to address this? I mean, it's not everything can be dealt with a drug. It's good for us to start to have the right diet to address this imbalance we have. We need to exercise. We need to have also a better, for example, other sort of lifestyle ways of less stress, sleeping a little bit. All of this will help you to really keep this balance and go on.

It's really multitude of …or I'm hoping as we move forward, we are going to have preventative measure that will depend more on the way of life we live, what we eat to balance this rather than always taking drugs or otherwise.

Andrea Wien: I would agree, and I think it makes sense to me that making sure you're going to the bathroom regularly so that these things aren't just sitting around having time to build the biofilms, right? If you're not stagnant in your digestive tract. So doing things like eating more fiber, increasing your vegetables, and getting your bowels moving. Seems like that would be a good way to keep this going.

Dr. Mahmoud Ghannoum: Yes, I really agree, and that is there's something maybe later on we can talk about down the line. I'm thinking I have started the work and research to try to understand how we really can rebalance the gut through a diet, for example, and other approaches, but we can talk about that. I'm sure in another occasion.

Andrea Wien: Dr. Ghannoum, always a pleasure. Thank you so much for coming in today. We will talk to you soon.

Dr. Mahmoud Ghannoum: Thank you very much. It's a great pleasure to talk to you. Bye bye.

Andrea Wien: Thanks so much for listening to part three of our three- part series Setting the Stage of the Microbiome. Next up we're talking SIBO. Until next time.


The Microbiome Report is powered by BIOHM Health.

Like what you hear, join us Thursdays here:

Thanks for listening

Thanks so much for listening to our podcast. If you enjoyed this episode and think that others could benefit from listening, please share it using the social media buttons on this page.

Feedback or questions about this episode? Email us

Subscribe to the podcast

If you would like to get automatic updates of new podcast episodes, you can subscribe to the podcast on iTunes, Stitcher, or from the podcast app on your mobile device.

Leave us an iTunes review

Ratings and reviews from our listeners are extremely valuable to us and greatly appreciated. They help our podcast rank higher on iTunes, which exposes our show to more awesome listeners like you. If you have a minute, please leave an honest review on iTunes.

Related Articles

  • Episode 77: How Crohn's and Ulcerative Colitis Are Wildly Different Than IBS

    The terms inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) get used interchangeably, but as we’ll learn in this episode, they are wildly different diagnoses with very different treatment...

  • Episode 76: Are You Doing Everything "Right" And Still Sick?

    It can be frustrating when you feel like you’re “doing everything right” and still not improving.  On this episode, Dr. Ami Kapadia joins Andrea to talk about persistent yeast overgrowth...

  • Episode 75: One Species' Trash Is Another's Treasure

    Typically, we don’t think about picking up the waste byproducts of another species and using them to our advantage. But when it comes to short chain fatty acids - the...