Why Do People Chew with Their Mouths Open? (Ft. Mark Cuban & Dr. Charles Spence)

Summary

Smart Girl Dumb Questions: Why Do People Chew with Their Mouths Open? (Ft. Mark Cuban & Dr. Charles Spence) Hosted by Nayeema Raza | Released April 11, 2025

---

Introduction: Setting the Stage for Curiosity

In this engaging episode of Smart Girl Dumb Questions, host Nayeema Raza dives into the sometimes pet peeve-inducing behavior of chewing with one’s mouth open. Framing the discussion within a broader cultural context, Nayeema emphasizes the importance of asking questions openly in a world saturated with information yet lacking in genuine curiosity.

“...overly confident hot takes. But what's scarce, I think, is asking questions and saying, I do not know.”
— Nayeema Raza [00:30]

Mark Cuban’s Curiosity: The Original Question

Nayeema begins by introducing her guest, billionaire entrepreneur Mark Cuban, who poses a seemingly simple yet intriguing question: “Why do people chew with their mouths open?” This question not only reveals a common social annoyance but also serves as a gateway to explore deeper psychological and cultural factors.

Mark Cuban: “Why do people chew with their mouths open knowing that 17% of the population is just annoyed as fuck.”
— Mark Cuban [00:00]

Diving Deeper: Misophonia and Social Etiquette

Mark Cuban elaborates on his annoyance, highlighting that a significant portion of the population finds open-mouth chewing bothersome. This sets the stage for Nayeema’s investigative journey to uncover the reasons behind this behavior.

“I have a data point. Data point is that 17% of people are annoyed by people eating with their mouths open.”
— Mark Cuban [02:15]

Expert Insight: Dr. Charles Spence on the Science of Chewing

To provide a comprehensive answer, Nayeema consults Dr. Charles Spence, a gastrophysicist from Oxford University. Dr. Spence explains the phenomenon of misophonia, a condition where certain sounds, like chewing, trigger intense emotional responses.

“Misophonia is a condition that affects some percentage of the population who tend to get very irritated by the sound of other people, especially eating.”
— Dr. Charles Spence [03:56]

He contrasts misophonia with ASMR (Autonomous Sensory Meridian Response), where similar sounds can evoke pleasure instead of irritation. Dr. Spence delves into the sensory aspects of eating, explaining how chewing with an open mouth can enhance the tasting experience by releasing more volatiles that contribute to flavor perception.

“Our favorite flavors or tastes are actually volatiles that are coming out of the back of the nose. And let's get the most of that air, most of those volatiles out through the back of your nose. You need to have your mouth open.”
— Dr. Charles Spence [06:38]

Cultural Perspectives: Beyond Personal Preferences

Dr. Spence also highlights cultural differences in eating behaviors. In some Asian cultures, slurping and open-mouth chewing are signs of appreciation for the food, contrasting sharply with Western etiquette that often frowns upon such practices.

“In Asia, there are cultures where lip smacking and slurping are a sign of your approval of the food that you have eaten.”
— Dr. Charles Spence [05:05]

Balancing Enjoyment and Social Norms

The conversation navigates the delicate balance between maximizing the sensory enjoyment of food and adhering to social norms that may deem open-mouth chewing impolite. Dr. Spence suggests that individuals with misophonia might choose dining companions carefully or work on educating others to mitigate discomfort.

“One might be just careful who one dines with, and maybe sort of educating people to change their attitude in a way.”
— Dr. Charles Spence [07:27]

Nayeema’s Reflection: Embracing the Pleasures of Eating

Reflecting on the insights, Nayeema humorously contemplates whether embracing open-mouth chewing could be seen as a form of empowerment—prioritizing the enjoyment of food over societal judgments.

“That's kind of like being a maximal foodie. Having cracked the code on the whole open mouth chewing thing, I'm ready for my next dumb question...”
— Nayeema Raza [08:16]

Teasing the Next Episode: Neil DeGrasse Tyson’s Question

The episode concludes with a teaser for the next installment, where astrophysicist Neil DeGrasse Tyson poses his own "dumb question" to Nayeema, highlighting the show's ongoing commitment to exploring the curious and the unconventional.

Neil DeGrasse Tyson: “How did they get the crane to the top of the building? I didn't see them put it up there. It's 50 stories up.”
— Neil DeGrasse Tyson [09:01]

Closing Thoughts: Encouraging Open Inquiry

Nayeema wraps up by inviting listeners to submit their own "dumb questions" and reiterates the show's mission to explore and demystify the everyday curiosities that often go unasked.

“If you have Dumb Questions and want me to find the answer. You can email me at [e-mail].”
— Nayeema Raza [09:06]

---

Key Takeaways

• Misophonia vs. ASMR: Understanding how different people can have opposite reactions to similar sounds during eating.
• Cultural Influences: Recognizing that eating behaviors like open-mouth chewing can be culturally significant and vary widely.
• Sensory Enhancement: Open-mouth chewing can enhance the tasting experience by releasing more flavor volatiles.
• Social Balance: Navigating the balance between sensory enjoyment and social etiquette can help mitigate discomfort for those with misophonia.

Notable Quotes

• “Why do people chew with their mouths open knowing that 17% of the population is just annoyed as fuck.”
  — Mark Cuban [00:00]

• “Misophonia is a condition that affects some percentage of the population who tend to get very irritated by the sound of other people, especially eating.”
  — Dr. Charles Spence [03:56]

• “Our favorite flavors or tastes are actually volatiles that are coming out of the back of the nose. And let's get the most of that air, most of those volatiles out through the back of your nose. You need to have your mouth open.”
  — Dr. Charles Spence [06:38]

• “That's kind of like being a maximal foodie. Having cracked the code on the whole open mouth chewing thing, I'm ready for my next dumb question...”
  — Nayeema Raza [08:16]

---

Connect with Smart Girl Dumb Questions

• Subscribe: Find the podcast on YouTube, Apple Podcasts, Spotify, or your favorite platform.
• Engage: Submit your own questions to [e-mail].
• Feedback: Follow and subscribe to stay updated on future episodes exploring the curious aspects of modern life.

Big thanks to Holly Thiel for editing and animating this episode's video content.

---

End of Summary

Transcript

[Mark Cuban]

Why would you do this knowing that 17% of the population is just annoyed as fuck.

[Nai Maraza]

Wow. Smart Girl dumb questions. So at the end of every episode of Smart Girl Dumb Questions, I ask my guests what they're dumb about. And it is my favorite part of the episode because it is such an escape from our know it all culture. And. And by that I mean this world where we're just supposed to know everything at every minute, whether it's that fancy foreign language item on our menu or an acronym. In the culture wars, we're supposed to know what it means and have a point of view like that. We have become so trained to ask our questions in the privacy of our chatgpts or Googles that we no longer ask them out loud anymore. So all of a sudden, everyone is a know it all. Whether you're a coastal elite professor or an aunt in Ohio or an underemployed DJ on Raya. So sorry, Joey. I had a great time. Call me. The world is abundant in information at our fingertips and overly confident hot takes. But what's scarce, I think, is asking questions and saying, I do not know. So in this investigative miniseries, I'll go and find the answers to things people like Mark Cuban, Neil DeGrasse Tyson, Cleo Abram Tamsen Fadal, and my Gen Alpha guest, Sophie and Dylan do not know. Welcome to CSI Dumb Question, where the dumbest thing you can be is a know it all. Right, here I am wearing this Olivia Benson pantsuit and I know I'm mixing metaphors here, guys, but bear with me. We're having fun. So, Mark Cuban, noted billionaire shark Tank guru, someone who people turn to for advice. What is he dumb about? I asked him and this is what I learned. Yeah. What is Mark Cuban dumb about?

[Mark Cuban]

Why do people chew with their mouths open?

[Nai Maraza]

Just show us what it would look like chewing with your mouth.

[Neil DeGrasse Tyson]

No.

[Mark Cuban]

That is my ultimate pet peeve, you know.

[Nai Maraza]

Mission accepted, Mark. I'm to find these answers for you. I'm going to find the answers to these.

[Mark Cuban]

I don't know why, but I do know from a thing I got from.

[Nai Maraza]

Are you going to tell me you know about the thing you're dumb about?

[Mark Cuban]

No, no, no, no. I can have one smidgen of of information, right? I can have a data point.

[Nai Maraza]

Tell me, tell me.

[Mark Cuban]

I have a data point.

[Nai Maraza]

Okay, what's your data point?

[Mark Cuban]

Data point is that 17% of people are annoyed by people eating with their mouths open.

[Nai Maraza]

I am in the Super 17.

[Mark Cuban]

Oh my God.

[Nai Maraza]

I'm like. That's like a no. Second Date situation for me, one of my best friends.

[Mark Cuban]

I will not go out to dinner with him. I'll go drinking. I'll do whatever.

[Nai Maraza]

So you want to know why do some people chew with their mouth open? Yeah.

[Mark Cuban]

I don't. Why would you do this knowing that 17% of the population is just annoyed as fuck?

[Nai Maraza]

So Mark's question sent me on a mission down a rabbit hole of like wild open mouth chewing videos and ASMR and scholarly articles. And this newspaper article that I finally found from 2022, and it's from the Telegraph, a British publication with a shocking headline, why you should ditch table manners and eat with your mouth open. I mean, guys, are you even English anymore? Another source for this is a University of Oxford professor. So we went across the pond virtually via Zoom, and met Dr. Charles Spence. He was chewing, of course. I appreciate, by the way that you're chewing, that you're eating while we're doing this, just so that when Mark listens to this, he'll be particularly annoyed. Professor Charles Spence, thank you for being with me.

[Professor Charles Spence]

It's a pleasure.

[Nai Maraza]

In a moment, we're going to ask Mark Cuban's question to you, but before we do that, could you just introduce yourself?

[Professor Charles Spence]

My name is Professor Charles Spence. I'm head of the Crossmodal Research Laboratory at Oxford University, a gastrophysicist interested in the senses and how we. What we see here, touch, taste and smell, affects what we like to eat and how much we enjoy the experience.

[Nai Maraza]

So first, maybe explain what misophonia is.

[Professor Charles Spence]

Misophonia is a kind of a recently invented name for a condition, affects some percentage of the population who tend to get very irritated by the sound of other people, especially eating. And that can trigger a kind of a rage, uncontrolled emotional response in those who experience it. And you might think of it as kind of, you know, the opposite of asmr, kind of the autonomous sensory meridian response where people very often get great pleasure about hearing other people whispering and crinkling paper. So these are two extreme responses to in particular, close sounds. And in the misophonia case, it really is the sounds of chewing. Sort of remember being a kid and always being irritated, dining at the family dinner table that my parents would have their mouth open. I didn't want to take any physical action, just kind of irritated me quietly. Maybe that's the English response.

[Nai Maraza]

So now why would people do this? Why would people chew with their mouth open? Your research provides a very compelling reason why people might do this.

[Professor Charles Spence]

So Mark probably doesn't want to go to a professional wine tasting or coffee cupping because if he does, he'll get very upset with all the slurping that goes on there. If you go to over in Asia, then there are cultures where lip smacking and slurping are a sign of your approval of the food that you have eaten. And not doing that would be rude by itself to be to eat quietly and silently. And so if we're given these sort of things, we, we did a study a few years ago with a chef in London, Joseph Youssef, having people consume a soup either with their mouth closed or with their mouth open, making a slurping sound or not. And we too found that those who slipped, they being English, they felt a bit self conscious about it, but they did enjoy the taste of their soup more than those who are forced to eat in silence.

[Nai Maraza]

And in. This is also what you found with chewing as well.

[Professor Charles Spence]

If you chew a potato chip, crunch it with your mouth closed, then all you're getting is bone conducted sound. Bite into something crispy or crunchy or crackly, or with snap with your mouth open, then you'll get both. The bone conducted sound, which is a bit dull really, but also the air conducted sound going out from the front of your mouth, round to your ears through the air. And that will give you an enhanced enjoyment through the sort of sonic texture that you get and that you get much better with your mouth open than with your mouth closed.

[Nai Maraza]

And that's the sonic texture sets in the, in the sound of the chewing. And then in terms of the aromatic.

[Professor Charles Spence]

As we sort of masticate food, chew it in our mouth, then we're releasing what are breaking down structures in the food in our mouth. We're releasing volatiles and mixing with the salt alive or all sorts of stuff going on. I mean our mouth can only tell us about sweet, salty, bitter, sour and umami. The basic tastes, which is pretty boring. It's what comes out of the back of our, of our noses through chewing and especially with our mouth open is all the rich volatiles that give us the, the meaty, the floral, the creamy, the herbal, the burnt, all those kind of things that we, we know and love in food. Our favorite flavors or tastes are actually volatiles that are coming out of the back of the nose. And let's get the most of that air, most of those volatiles out through the back of your nose. You need to have your mouth open.

[Nai Maraza]

All right, so how do you kind of square this? You know what's reportedly one out of five people who struggle with Misophonia versus the joy that we could have with chewing with our mouths open.

[Professor Charles Spence]

One might be just careful who one dines with, as I think we heard in the clip a little bit earlier on, and maybe sort of educating people to change their. Their attitude in a way.

[Nai Maraza]

Do you ever worry, I mean, you're an Englishman, that you're kind of ruling yourself out from being knighted by the king because you are taking down English etiquette?

[Professor Charles Spence]

Well, yeah. So if you caught me at High table and Somerville College where I teach them, I probably will have be easy with my mouth closed, despite what I just said.

[Nai Maraza]

Hypocrisy. All right, thank you so much, Dr. Spence.

[Professor Charles Spence]

Thank you.

[Nai Maraza]

Okay, well, now we know, guys, that chewing with your mouth open can make things yummier because it sounds better, it smells better, and therefore it tastes better. I mean, I'm shocked and I don't know now if I will all of a sudden think that chewing with your mouth open is like a sign of emboldenment, a sign of, like, being powerful, actually, because you don't give a fuck what society thinks. You just want your food to taste really good. And that's kind of hot. That's kind of like being a maximal foodie. Having cracked the code on the whole open mouth chewing thing, I'm ready for my next dumb question, and this one comes from Neil DeGrasse Tyson. What is Neil DeGrasse Tyson dumb about, if anything?

[Neil DeGrasse Tyson]

Oh, anytime I'm in the company of someone who knows anything that I don't know, that's all I want to talk about. Let's say it's a construction worker.

[Nai Maraza]

Okay.

[Neil DeGrasse Tyson]

How did they get the crane to the top of the building?

[Nai Maraza]

How did they get the crane?

[Neil DeGrasse Tyson]

The crane at the top. I didn't see them put it up there. It's 50 stories up.

[Nai Maraza]

That's down there. I love that this astrophysicist had a question for a construction worker. And thankfully I live in New York City, so I can just go outside and find the answer. But that's to be continued on the next CSI Dumb Questions. In the meantime, if you want to know all the things Mark Cuban does know, you can get my full Smart Girl Dumb Questions hour with Mark at the link below. We talk about capitalism, why healthcare sucks, and what it's like to be smart. So damn rich. I'll be back next week with a fresh episode of Smart Girl Dumb Questions. Find us on YouTube, Apple, Spotify, or wherever you get your podcasts. And hit subscribe or follow if you have Dumb Questions and want me to find the answer. You can email me at naimaraza101gmail.com and I want to say a big thanks to the wonderful Holly Thiel, my partner in crime, on this episode, for editing and animating this video.