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Halitosis with Dr. Bernard J. Hennessy

10/02/23 Bernard J. Hennessy, DDS, Texas A&M University, College of Dentistry;

Season 5 | Episode 2



Title: Halitosis

Joe McIntyre (Host): Welcome to another episode of the Merck Manuals Medical Myths podcast. On this show, we set the record straight on today's most talked about medical topics and questions. I'm your host Joe McIntyre. On this episode, we welcome Dr. Bernard J. Hennessy, DDS, which is Doctor of Dental Surgery, at Texas A&M University School of Dentistry. We're going to be discussing a topic that can be quite embarrassing for a number of people, halitosis, or more commonly known as bad breath. Dr. Hennessy, thanks for joining us.

Dr. Bernard J. Hennessy: Thanks for having me.

Host: So let's start off with a little bit of the basics here, what exactly is halitosis and what causes it?

Dr. Hennessy: Halitosis is obviously probably well known to a lot of people. And as you said in your intro, it's another way to describe bad breath. And there's multiple causes that could be as simple as foods that we eat, but most likely, the majority of them are probably related to bacteria in our mouth, and dealing with foods, when they break things down and cause bad breath.

Host: How common is halitosis?

Dr. Hennessy: You know, if you read it or get into literature to read about it, there's different numbers on how to report it, but it's probably up to 25% of the population may have persistent bad breath. Some studies report numbers a little bit lower, 15% to 25%, probably in the range.

Host: Now, when it comes to bad breath, is it something that society has deemed this to be bad breath? Or is there something in our psyche that tells us that this person's breath is a foul smell or foul odor? And how does that kind of come to be?

Dr. Hennessy: Yeah, I think probably depending on how closely we interact with people, the spaces we're in, but I think we all are sensitive to it. And there's certain odors that I think we would pick up and you kind of know someone just had a meal or something may be more intense in a way.

Host: Got it. Now let's dive into some of the myths and misconceptions a little bit. Do mouthwashes or breath mints get rid of bad breath?

Dr. Hennessy: Mouthwashes and breath mints, they could help mask bad breath. But, if a mouth rinse would say, “Hey, use this product and eliminate your bad breath.” That's not true. It can temporarily mask it, but not necessarily eliminate it. 

Host: As we've talked about, so many of us are self-conscious about having bad breath, whether it's on a date, you're out with someone, you're out with friends, you're out with family. Can you tell if you have bad breath, if you breathe into your cupped hands?

Dr. Hennessy: You know, I bet you probably most people have tried that because you're not sure. But the truth is, you probably get used to your own breath. And so that wouldn't really be an effective way. You might be thinking you're good. And maybe a friend would tell you you're not. 

Host: It's a tough scene. You mentioned mouthwashes don't get rid of bad breath, mostly cover it. What about brushing your teeth? Is that the same kind of thing? 

Dr. Hennessy: Well, certainly brushing your teeth because most of the causes of bad breath originate in the mouth. Effective brushing of teeth is certainly going to help. But it's not just the teeth, we have the tongue, there's a lot of surface area on the tongue. Food particles and bacteria can get stuck on there. So, I think people maybe don't always brush their tongue effectively. That's another part of the brushing, and brush again, tongue and teeth. And then brushing doesn't always deal with the food and bacteria that can get in between teeth, and we have to use something to eliminate that like floss. There are mechanical devices, things like that, that probably would contribute to reducing bad breath.

Host: You mentioned effectively brushing your tongue, I know this is an audio only medium. So try to be as descriptive as you can, what is the best way to brush your tongue to get rid of some of those bacteria and avoid bad breath?

Dr. Hennessy: You could buy devices, tongue scrapers. Some of us have more of the extensions that we call filiform papilla, things that stick up on your tongue, and so they might benefit from a scraper. Most of us could just use your toothbrush, and just kind of brush the product from back to front, not too far back, you'll gag yourself. And I think that's an effective way to clean your tongue for most of us.

Host: If you are on a date, or just want to avoid getting bad breath in general, what sorts of foods or drinks should you avoid?

Dr. Hennessy: It's interesting, depending on when you're on a date, you might want to have a glass of wine or something. Sometimes alcohol is one of the things that could contribute to that. Certain foods, things with garlic, some spicy things, onions, foods like that. I don't think it would mean you wouldn't have to not order them on the menu. But I think you'd have to just be aware that that could change your breath. And certainly, if anyone were a smoker as well, that combination of smoking and alcohol probably would contribute to some bad breath.

Host: Are there any particular diets that would cause bad breath more so than others?

Dr. Hennessy: You know, I think that if you think about diets and bad breath, the keto diet is one of the things there. The way that diet is structured is that it's high in fat, and if the body is forced to use fats for energy, it can break down fats into ketones, which can have an acetone, nail polish-type smell. I think some people on a keto diet might experience that. But beyond that, I'm not aware of too many other diets that might affect that.

Host: Now, you're a dentist, I'm sure you hear people talking about everything dealing with the mouth all the time. So are there any other myths about halitosis that you've heard or that have come across to you in your career that you may want to debunk? 

Dr. Hennessy: I've heard things like bad breath originates from the stomach, not from the mouth. And that's not true, there's certainly a few things, a very small percentage of medical conditions, that could contribute to bad breath. That's one of them. Another thing was, we kind of already talked about, mouth rinses carrying bad breath. They can help mask, but they don't cure. And then even things like chewing on certain green leafy vegetables or leaves or things that maybe have a nice fresh scent, but they also might be high in chlorophyll or something. And the thought was, “Oh, chlorophyll is going to kind of purify your breath.” There's nothing to that. Another myth.

Host: Yeah, another natural remedy, I think we've seen or heard of before, is using maybe peppermint oil as a way to mask it, is that helping prevent it at all?

Dr. Hennessy: Certainly, in peppermint candies and things, you could mask things. And I think the way I understand, some of those oils are not necessarily well-regulated to be ingested. I probably wouldn't recommend anyone doing that. I think a peppermint or if you could find a couple of sugar-free mints as dentist speaking, that would probably be ok.

Host: So when you said you can't breathe in your cupped hands to kind of tell if you had bad breath, obviously, I panicked. Because that means how would I even know if I have bad breath or not? So is there any way to tell if you have bad breath or not without someone directly saying, “Hey, buddy, you have bad breath,”?

Dr. Hennessy: You know, unless you did some kind of gas chromatography or something to test, I think a lot of times it's going to be a friend or partner. Someone might say, “Hey, you know, you need to chew some gum or something.” It's hard to do it ourselves.

Host: Just get better friends. That seems like a viable resolution.

Dr. Hennessy: I think, we can all use better friends, more friends, probably.

Host: Can certain medications cause halitosis as a side effect.

Dr. Hennessy: There's probably a few, maybe uncommon meds, it's in case reports, in the literature of some uncommon things. But there are a lot of common medications like blood pressure meds that have side effects, where they literally dry the mouth, and that's not just that type of medication. So that's pretty common. And then as our mouth gets dry, we tend to have a tendency for more bad breath. You don't have the saliva that naturally kind of lubricates and flushes things away. Got it?

Host: I think you kind of mentioned this already. But just to confirm how halitosis pretty much only originates in the mouth, it doesn't really come from other parts of the body. Except for some more, you know, rare circumstances, correct?

Dr. Hennessy: Sure. You could probably say about 10% of causes could be something other than the mouth. If someone had issues with bad breath, I think starting with a dentist and working on hygiene and things like that is the best way to proceed. If that didn't work and there was some persistent thing, then it certainly would be worth a referral to a medical colleague, ENT specialist. Maybe there are things that could cause bad breath. For instance, even related to the keto diet, diabetes/uncontrolled diabetes could cause the same type of ketoacidosis that you could get to that acetone smell. There's certain things with the liver that could cause a musty smell, these things get into the blood and then these gases get expelled through the lungs. So we could pick up on things. Someone had an abscess in the tonsil, perhaps, or something in the lung. But that's a very small percentage of causes of bad breath.

Host: Okay, can halitosis be a sign of more serious underlying health issues? Or is it kind of just there? It's just a symptom of poor hygiene or something else?

Dr. Hennessy: Yeah, kind of falling on our previous question there. It could be a small percentage of things. Certainly, I think persistent halitosis that people have run through everything that a dentist would recommend, it probably would warrant a further look.

Host: Let's say you're going to the dentist, as you probably should every six months or so. Is there anything you should do to prepare for going to the dentist to make sure that you're having a good experience, whether it's flossing or brushing before but even beyond the hour before? Avoid having lunch doing this? Is there anything you should do as you're going to the dentist? You know, some tips as you go into your office?

Dr. Hennessy: If you're going to the dentist with a specific complaint of halitosis, it certainly would be good to avoid any kind of food that could maybe contribute to that and maybe mask what you're really dealing with. But I think the other part of going to the dentist is just having your teeth as clean as possible, it makes it easier for the dentist to see what's going on in there. As a youngster, I used to think that if I hadn't brushed my teeth for a long time, I could spend about 10 minutes before I went to the dentist, but generally making your teeth a little bit cleaner was not going to cure other things. 

Host: Are there any stories? You've been a dentist for a while and any stories that come to mind about someone being confused about halitosis and you help them with the solution, anything that would help our listeners understand that this is a common issue, and nothing to really be embarrassed about but something that can be treated.

Dr. Hennessy: Well, I don't think I have a super great story, but I've had certainly a number of patients where they've been dealing with halitosis for a while and maybe trying to use mouth rinses and things with maybe minimal success. But when you get down and you're able to show them, maybe you haven't been brushing your tongue or maybe they have prominent tonsils, they have Crips, where food and things can be caught in there and that can contribute to kind of odor. So I think there's common, easy things that can be done for a lot of patients that would help them deal with this and feel better about it.

Host: Dr. Hennessy, as we close out the conversation here, where should our listeners go to learn more about the symptoms, diagnosis, prevention, or anything else regarding halitosis?

Dr. Hennessy: Well, there's certainly a lot of resources for people to find things. Certainly, go into the Merck Manuals, is a great place to start in the consumer edition. There's a lot of information related to this, like the American Dental Association, they have a consumer site where you can learn about brushing and flossing and devices that might help keep things clean. I think those are two really good places to start.

Host: Well, Dr. Hennessy, thank you so much for joining us on this podcast. Certainly, a great conversation busting some of the myths about halitosis. As we close out. I'll let you leave our listeners with the final word.

Dr. Hennessy: Medical knowledge is power. Pass it on. Thank you.