How GPS Quietly Runs the World & When Illness Has No Obvious Cause

Summary

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Podcast Summary: Something You Should Know

Host: Mike Carruthers
Episode Title: How GPS Quietly Runs the World & When Illness Has No Obvious Cause
Release Date: June 29, 2026

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Episode Overview

This episode is a two-part exploration of how hidden forces shape modern life. First, Mike Carruthers interviews journalist Katharine Dunn about Global Positioning System (GPS) — delving beyond navigation and into GPS’s profound but underappreciated role in banking, shipping, the internet, and more. In the second half, Dr. Susan Trachman, a specialist in psychosomatic medicine, discusses the often misunderstood field of "medically unexplained symptoms," the mind-body connection, and why some very real physical illnesses elude typical diagnoses.

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Key Topics and Insights

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The Hidden Reach of GPS

Guest: Katharine Dunn, journalist and author of Little Blue: How GPS Shaped the Modern World
Segment: 03:15 to 27:45

What GPS Really Is and How It Works

• GPS is not just about finding coffee shops or avoiding traffic; it’s a critical backbone of modern infrastructure (banking, internet, emergency services).
• How it works (06:11):
  • The Earth is encircled by satellites sending one-way signals to receivers (like your phone).
  • Location is determined not by triangulation, but by measuring tiny differences in the arrival time of signals from at least four satellites — longitude, latitude, elevation, and, crucially, time.
  • Quote:

    "Our day to day experience with GPS is Google Maps navigating around. But what the satellites also provide... are atomic clocks, so they're providing extremely accurate time to clocks that are not very good, like the one on my iPhone."
    — Katharine Dunn, 00:46 & 21:16

The Genius of One-Way Signals

• GPS satellites “rain” information down like a shower; they never know who or what received the signal.
• Security feature: Built to work anywhere on Earth without betraying military users’ locations.
• Only by combining GPS with telecom networks and apps does location become trackable by others.
• Quote:

  "It's like being underneath a shower head. It's just raining down on you, basically... The satellites don’t individually know where you are."
  — Katharine Dunn, 07:53

Why GPS Still Works in Tunnels or Garages

• Devices use predictive algorithms and stored satellite movement data to guess location when signal is lost, “correcting” itself as soon as possible.
• Quote:

  “It's this constant process of test and refine, test and refine... the level of computing that needed to go into this system was something pretty incredible.”
  — Katharine Dunn, 11:18

Origins: Built for War, Adopted by the World

• Born out of the US military’s need for precise bombing (post-Vietnam, 1970s), GPS was unpopular and underfunded at first.
• The system only became super-accurate and civilian-accessible after 2000.
• Quote:

  "It was constantly at risk of getting its budget cut, even canceled ... Only essentially from 2000 that it became as accessible to civilians, that it became as fast and as super, super accurate as we understand it now."
  — Katharine Dunn, 13:35

First GPS Cars: Made in Japan

• Japan led car GPS adoption, using the system for earthquake monitoring, fishing fleets—and, by 1989, luxury show cars.
• US automakers followed in the 2000s as GPS and mobile chip technology improved.
• Quote:

  "The people who had the idea to put it in cars were first and foremost the Japanese... these really elite futuristic cars."
  — Katharine Dunn, 18:42

The Money — and Free Access

• Still run by the US military; operating costs covered by US taxpayers.
• Tech companies, logistics firms, and app makers profit massively by building services on top of free GPS data.
• "No one pays for GPS:" Google, Apple, Uber, etc., piggyback on public infrastructure.
• Quote:

  "It's taxpayer dollars... If you think about Uber, you think about these dating apps, all of this location-based service... is unimaginable without GPS."
  — Katharine Dunn, 21:16

The Time Factor

• GPS satellites keep the world’s clocks, stitching together synchronized timing for everything digital.
• "Heartbeat" analogy: The entire global digital system depends on the ultra-accurate time GPS provides.

GPS Is the Skeleton—Apps Are the Flesh

• All your map and traffic data? That’s not GPS, but app-layer computation using GPS’s basic location/time output.
• Fundamental limitations: Still a 1970s system at its heart, though newer versions (China's Beidou, Europe's Galileo) are more advanced/two-way.
• Quote:

  "GPS is basically location and time. It is what it is."
  — Mike Carruthers, 23:35

Subtle Influence and Global Dependence

• Because it’s free and omnipresent, GPS “slipped under the radar” into every aspect of life and business.
• Industries have boomed—and others (like map-making) have nearly died.

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When Illness Has No Obvious Cause

Guest: Dr. Susan Trachman, specialist in psychosomatic medicine, author of It’s Not Just in Your Head
Segment: 28:50 to 47:19

Why Mysterious Symptoms Are So Common

• Many people have physical symptoms that doctors cannot find a physical cause for—chronic pain, fatigue, gut problems, etc.
• "Medically unexplained symptoms" (MUS) account for a significant share of doctor visits.
• Quote:

  "40% of visits to a primary care doctor are for general symptoms... and in only 25%... can a biological diagnosis be found."
  — Dr. Susan Trachman, 34:45

The Reality of the Mind-Body Connection

• The brain is not separate from the body; they’re always communicating (“like besties who text all the time"—via nerves/hormones).
• Brain stress/anxiety can cause very real physical effects—on the gut (IBS), cardiovascular system, and even autoimmunity.
• Quote:

  “Whatever's going on in your brain is going to affect various organ systems and vice versa... a classic example is the brain-gut connection.”
  — Dr. Susan Trachman, 30:30

The Danger of Dismissal

• Patients often feel invalidated when told their symptoms are “all in their head.”
• Dr. Trachman reframes: The brain is in your head, but its influence over the body is real—not imaginary or trivial.
• Quote:

  “You can imagine how that would be very dismissive or demeaning... It's self doubt. So it can impact you psychologically.”
  — Dr. Susan Trachman, 34:20 & 37:29

Environmental and Social Stressors Play a Huge Role

• Factors like workplace toxicity, exposures (mold, chemicals), and social environment can cause symptoms even if not detectable by standard tests.
• Modern medicine’s specialization can cause doctors to overlook root non-physical causes.

Numbers: Not So Rare

• Estimated 80 million Americans have medically unexplained symptoms.
• Frequent doctor-shopping and excessive testing can cause psychological distress and huge healthcare costs.

How to Navigate a Mystery Illness

• Don’t settle for “it’s nothing” if you’re certain something is wrong.
• Seek out well-reviewed providers; ask about additional testing and specialist referrals.
• Track your symptoms, bring written questions to appointments, and advocate for deeper investigation.
• Quote:

  “Patients know their bodies better than anybody... you wouldn't hire a plumber without looking at their reviews.”
  — Dr. Susan Trachman, 43:16

The Path to Healing

• Addressing stress/anxiety can often alleviate physical symptoms (e.g., treating anxiety may resolve IBS or lessen autoimmune flares).
• Lifestyle changes—exercise, quality sleep, healthy diet, and social support—can activate the parasympathetic ("rest and digest") system and improve well-being.
• Quote:

  “There are things we can do to stimulate that part of our nervous system… exercise... sleep... healthy diet... social outlets.”
  — Dr. Susan Trachman, 45:32

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Notable Quotes and Memorable Moments

• On GPS as Infrastructure:

  "GPS quietly runs much of the modern world. Everything from banking and shipping to farming, emergency services, power grids, and the Internet itself depends on its timing signals."
  — Mike Carruthers, 03:32

• On Medical Frustration:

  "I had one patient whose doctor said, go read a book, which was absurd, right? I mean, it's good to read a book, but it had nothing to do with why her blood pressure was elevated."
  — Dr. Susan Trachman, 43:55

• On the Spread of GPS:

  "It was a tool of power as well—whole countries’ civil infrastructure, their airports, their energy grids... becoming dependent on this system."
  — Katherine Dunn, 26:08

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Timestamped Breakdown

| Timestamp | Segment Title/Theme | Summary/Notable Topics | |-------------|-----------------------------------------------------|----------------------------------------------------------| | 00:32-03:15 | Introduction & Why Phone Conversations Distract Us | Psychological reason: brains try to fill in “missing halves” of conversations ("halfalogs"). | | 03:15-15:36 | All About GPS: What, How, and Origins | Deep dive into how GPS works, why it’s unique, and why it was created. | | 15:36-27:45 | From Military to Consumer, Economic Impact | Japan’s early adoption in cars, GPS’s spread, free access, and dependence in modern life. | | 28:50-47:19 | Medically Unexplained Symptoms & Mind-Body Medicine | Why “it’s all in your head” doesn’t mean imaginary; prevalence, patient advice, hope for solutions. | | 47:25-48:50 | Why Athletes Grunt | Brief science tip: grunting increases strength via core stabilization. |

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Final Thoughts

The episode illuminates key “invisible” mechanisms of modern society—how GPS is a universally free yet profoundly foundational technology, and how our mental and social environment can create or amplify very real physical health conditions. Through expert voices and relatable explanations, it conveys not just facts, but context for living in—and navigating—the modern world.

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Transcript

[Mike Carruthers]

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today on something you should know why listening to a person talk on their phone to someone else can be dangerous for you. Then the fascinating story of GPS and things about it you may not know.

[Katherine Dunn]

Our day to day experience with GPS is Google Maps navigating around. But what the satellites also provide is they have atomic clocks, so they're providing extremely accurate time to clocks that are not very good, like the one on my iPhone.

[Mike Carruthers]

Also, why do tennis players and weightlifters grunt so loudly? And when you know you're sick but the doctor can't find anything wrong, it can be really discouraging. And it happens to a lot of

[Dr. Susan Trachman]

people who go from doctor to doctor. And when the physician cannot come up with a diagnosis, they might say to the patient, we really can't find anything wrong with you. It's all in your head. Go see a psychiatrist. Which is how they end up in my office.

[Mike Carruthers]

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something you should KNOW Fascinating intel, the world's top experts and practical advice you can use in your life. Today, Something you Should Know with Mike Carruthers.

You know what can be really annoying and distracting is listening to someone else talk on their phone to someone else. And it can have some important consequences you should probably be aware of. Which is why we're starting with that today on this episode of Something youg Should Know. Hi, I'm Micah Ruthers. Thanks for joining me today. So you ever notice how hard it is to ignore someone else's cell phone conversation? You might be reading or working or driving along just fine until the person next to you starts talking on the phone to someone else. And then suddenly you can't concentrate. Psychologists have a name for it. It's called hearing only one side of a conversation. Research shows that halfalogs are more distracting than listening to two people talk face to face. And the reason is your brain is naturally wired to to predict what comes next in a conversation. So when you hear only one side, your mind keeps trying to fill in the blanks, which quietly steals your attention away from whatever you're doing. This can become problematic if you're driving your car and your passenger starts a phone call with someone else. That can be very distracting for you while you're trying to pay attention and drive the car. And that is something you should know. When was the last time you were trying to figure out how to get somewhere and actually pulled out a paper map? For most of us, it's been years. Today we simply pull out our phone, tap in an address, and a calm voice tells us exactly where to go. It is truly amazing. And yet GPS wasn't created to help people find coffee shops and avoid traffic. And it was built for the military. It is operated by the US Government, it costs billions of dollars to maintain, and yet anyone on earth can use it for free. GPS doesn't just help you get from point A to point B. It quietly runs much of the modern world. Everything from banking and shipping to farming, emergency services, power grids, and the Internet itself depends on its timing signals. So how does it all work? Where did it come from? Who runs it, and why is it free? Here to explain is Katherine Dunn She's a business reporter and editor who works at the Reuters Institute for the Study of Journalism at the University of Oxford, and she's author of the book Little Blue How GPS Shaped the Modern World. Hey, Katharine, welcome to something you should know.

[Katherine Dunn]

Hi, thanks for having me.

[Mike Carruthers]

So before we get into the history of gps, which I think is a rather fascinating history, explain to me in basic language how does it work?

[Katherine Dunn]

The globe is basically encircled by a series of satellites. We're talking about the US Global positioning system here. But now there's a bunch of these systems run by different governments and they all operate on more or less the same idea. So the globe is encircled by these satellites and you're sort of in sight of minimum four of them at any time. And people often think it's, oh, it's about triangulation, but actually your location is being found on Earth through time. So the satellites are sending out a signal from space. And say you have your phone, I have my iPhone next to me. It's actually calculating the length of time it takes for a radio signal to reach you on Earth. And it does that three times, longitude, latitude and elevation. So it calculates your position in three dimensions. And then the fourth one actually calculates time, which is arguably the most important and sort of the trickiest to explain. But yeah, you're looking at four, four sort of dimensions here. Longitude, latitude, elevation and time. And that situates where you are on Earth. But it's really about making that calculation. We can do that because electromagnetic waves move in a vacuum. They move at a steady, known speed, and that's from Einstein. So this is really putting a lot of Einstein's theories into practice and helping us understand where and when we are on Earth.

[Mike Carruthers]

So those four satellites that find my phone and communicate with my phone, is my phone communicating back with it or not?

[Katherine Dunn]

So one thing you have to know about GPS is it's actually a one way system. So the satellites collectively don't know where you are. It's all one way. So you can think of it. It's like being underneath a shower head. It's just raining down on you, basically. And what turns it into a two way system is the way that your phone is stitched into all of these other things, you know, telecommunications systems and wireless networks and that sort of thing. So, yeah, the satellites don't individually know where you are, none of the system knows where you are. And the reason it's like that is because it was built for conflict. Right. So the whole idea was that you could use it wherever you were on Earth, but it wouldn't simultaneously give you away if somebody was looking for you. So that's one way to think about it. We do think of it as a two way trackable system, but the trackable element comes from all the other aspects of technology that interact with GPS and the way that we use it.

[Mike Carruthers]

And so the signals are coming in and it's the phone or the thing in my car or whatever that is making sense of those signals and turning it into a dot on the map.

[Katherine Dunn]

Yeah, exactly. The math on one level is pretty simple. You've got four equations. But actually this is like a computer in space talking to a computer in your phone, talking to other computers at base station as part of the U.S. government. This whole system is a U.S. government system. So actually what's going on here is incredibly complicated. It's a lot of different computers talking to each other. That's kind of the core of it.

[Mike Carruthers]

Something I've always wondered about. Gps. When I'm using it, for example, if the satellites are finding my phone and sending signals to it, how does it know where I am? How does it do that? When I'm say, at the bottom of a parking structure or in a tunnel where theoretically radio signals can't get to it, how does it know where I am?

[Katherine Dunn]

Basically, the US Government puts together sort of a predictive list of where all the satellites are going to be in the next however many hours. So if you've ever wondered, sometimes if you get off a plane, for example, and you don't have data reception yet, or you don't have other things, and your phone can kind of give you an indication of where you are. Right. If you just open Google Maps, for example. Part of this is there is a predictive element built into it. And your phone and the chip inside your phone is interacting also with a database, so it can make a guess of where you are even when it doesn't actively have all of those satellites within sight. This is one of the things that allows your phone, if you open Google Maps or something, to connect so, so, so, so quickly to your location is the fact that it has some indication of where the satellites are and therefore where you are. And so it kind of makes a jump, it makes a prediction, and from that prediction it can adjust.

[Mike Carruthers]

So yeah, so it's kind of making assumptions about where it's likely that you are when it can't see you and then it'll recorrect itself when it does see you.

[Katherine Dunn]

Yeah, exactly. It's this constant process of test and refine, test and refine, and test and refine. And the reason all of this testing and refining can happen is because, of course, we're dealing with chips and we're dealing with computers. When this whole system was created, it was something pretty incredible. The level of computing that needed to go into a system like this and the fact that we're still using it today, basically more or less as it was designed.

[Mike Carruthers]

Is it possible to know how many people or businesses or how many users there are of GPS at any one time? Or you gave the analogy that the information is one way, like a shower where it's just coming out of the shower, that you wouldn't really know how many people are getting wet.

[Katherine Dunn]

So we have no idea how many people are using GPS at any one time or the other systems that are similar to GPS run by other governments. We have no idea, you know, how many people are collectively using these systems. It's not even how many people. It's how many chips and electricity grids or cars or all of these different pieces of technology. Right. Because it's just sort of raining down on you. It's passive. From the beginning, when they were looking at how popular GPS was becoming with civilians, one of the things the US Government didn't know is how many people are actually using this thing. How popular is it for civilians outside of military uses? And they could only guess, really, based on how many sort of receivers were maybe being sold or who was making chips. But it was just that it was a guess. We don't know how many people are using it at any one time.

[Mike Carruthers]

Well, it's kind of like if you were operating a radio station and sending out a signal, you don't know who's listening.

[Katherine Dunn]

Exactly. It's exactly like that. It's radio waves, and you don't know who's on the other side. Which is interesting, when the US Government has developed a tool that's, you know, it's a military tool, but they realized fairly early on, oh, whoever they were up against could use it as well.

[Mike Carruthers]

I know the history of GPS is. I find this story pretty interesting, and I'd like to get you to tell it. You could probably go for hours on this topic. But just in a nutshell, what is the story? The history of gps?

[Katherine Dunn]

The GPS system as we know it now is from the early 1970s, and it essentially emerged out of the end of the Vietnam War as a tool to bomb. More precisely, this had been a real issue in the Vietnam War, this lack of ability to really precision bomb and There were a lot of different competing systems within the US Military, systems that could do one thing better or another thing better. There had been a predating system that came out of the late 50s. And so this was sort of a refinement of a lot of ideas that had been building and building and building. But yeah, it was essentially a tool to make bombing more precise. And it needed to work in three dimensions because you were really thinking at that time about, you know, fighter jets or missiles or things where you were working in three dimensions. So you have the system and it's sort of in the bowels of the Pentagon. It's designed, they're testing it, they're trying trialing it. If you think about it, it's, you know, it's incredibly, incredibly, incredibly expensive program because you're launching satellites. Right. And one of the really surprising things about it that I was very surprised by it was it wasn't popular in the Pentagon. It wasn't like people automatically saw, oh, this is something transformative that we really, really want. Let's shell out loads of money for it, let's keep it going. It was constantly at risk of getting its budget cut, even canceled. So over time, you're looking at decades to get the system up to the way we see it today. And the way we see it today is only essentially from 2000 that it became as accessible to civilians, that it became as fast and as super, super accurate as we understand it now. And it started being put in, you know, cars and cell phones, kind of in a mass scale.

[Mike Carruthers]

Yeah, I want to find out more about that, about how it moved from being a military thing to becoming basically a consumer product. And we'll do that in just a moment.

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[Katherine Dunn]

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[Dr. Susan Trachman]

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[Mike Carruthers]

We're talking about GPS and my guest is Katherine Dunn, author of the book Little Blue How GPS Shaped the Modern World. And Katherine, I'm really curious how GPS got in cars because as you said, it was a military thing and somebody must have been sitting around going, hey, I have an idea. Why don't we put it in cars and then people can know where they are and know where they're going. How did that all start?

[Katherine Dunn]

The people who had the idea to put it in cars were first and foremost the Japanese. So as it starts leaking out of the US military, as they get enough satellites up that you can get they call It a fix, you can get a location and a time to stop some extent at some time. Nothing like what we have now, but still really, really amazing. It started kind of leaking out of the military and quite quickly what you saw happening is people realizing the potential. So in Japan, they realized really early on that this was going to be useful for managing earthquakes. They were going to put it on buildings and see how they were shifting and using it to track things. They started using it on boats really early. They started using it on fishing fleets. Really. And then, yeah, it was really the Japanese who thought, okay, we can put this in a car. But when they started putting it in cars, it was these really elite futuristic cars. They were sort of in this battle with the US at the time, in the late 80s to produce these incredible futuristic cars with computer consoles and things that have now become really standard. So it started showing up in these sort of show cars. The same year that GPS appeared in a car at the Tokyo Motor show was the same year that they had a car that was modeled after like the Batmobile.

[Mike Carruthers]

And what year was that?

[Katherine Dunn]

That was 1989. It was right, right before the Berlin Wall fell. It was also right before Japan's economy crashed.

[Mike Carruthers]

And so it started to appear in cars regularly. When, around 2000?

[Katherine Dunn]

Yeah, around the 2000s. So through the 90s, it was sort of this real high tech novelty thing in Japan. It didn't work to that well. But what happened in 2000, GPS got a lot more accurate for the average person. And this coincided with sort of the digital revolution where you started getting these really, really small chips, right? You started getting mobile phones. By 2007, you have, you have the iPhone. And in the meantime, if you remember TomTom and you remember these navigation devices you could put in your car, that was really like the boom, I would say, you know, sort of 2000 to 2007, 2008. That was really when average people got this in their car and they realized how useful it was.

[Mike Carruthers]

And so does anybody make money on this? Well, who operates those satellites? Is it still the military?

[Katherine Dunn]

Yep, it's the US military. I mean, who pays for it is the US taxpayer. But at the same time, when you think what comes back in the form of who makes money off of it would be all sorts. Every business with logistics, the tech companies, it's just, it's so unimaginable almost at this point for these businesses to run without gps. If you think about Uber, you think about these dating apps, you know, they maybe work with Wi Fi, they work with all these Other things, but all of this location based services and never mind global trade. And one of the points that I think is really easy to miss is actually that just as important, sometimes more important is time, is the fact that GPS provides extraordinarily cheap and accurate time. And of course our day to day experience with GPS is, you know, is Google Maps as your car is navigating around. But what the satellites also provide is they have atomic clocks. So they're providing extremely, extremely accurate time to clocks that are not very good, like the one in my iPhone. And it creates this sort of stitch and this synchronization that we really need for digital life. We need it for electricity grids, we need it for all kinds of digital systems. We need to know that the email will leave at X time and it arrives at X time. It's like this heartbeat, right, where everything sort of synced up.

[Mike Carruthers]

One of the things now though, with gps, the way people use it, which is I think primarily, you know, with maps and things like that, you get all this other information that's not gps, right? That's not calculating your trip time, that's not telling you how bad the traffic is. GPS is really just telling you where you are. Is that a fair statement?

[Katherine Dunn]

Yeah, but where you are, but then also that's everybody else's location is also based on gps. It's sort of like a skeleton underneath a lot of things, sort of stitching everything together. And then we, you know, things get layered on top obviously, but the basic location and the basic time is, is really gps.

[Mike Carruthers]

So if I'm understanding all of this correctly, GPS is essentially and only a system that tracks your location and time. Everything else that you see on say Google Maps or Waze or whatever, all that other information, that's not gps, that's Google Maps or Waze layering on top of the GPS location, traffic conditions, where the restaurants are, that's not gps. So GPS is basically location and time. It is what it is.

[Katherine Dunn]

I think GPS is what it is. You have to remember this is still a system from the 70s, it still follows those core principles. What people have often said to me is that the Chinese equivalent of gps, beidou, it is a lot more complex, it's more satellites. Some people say there's, there is a two way element there, there is a transmission element. So you do have these newer systems, this is a much, much, much newer system. Like from the early 2000 kind of, we're talking about it, you know, coming up to speed. Even Galileo is sort of late 90s, 2000s. You're moving into the launching of satellites. So they're newer systems and then they are more complex. But yeah, the, the fundamental idea of gps, the way we've been using it, I can't imagine it really changing, but people are still finding new and interesting ways to use it.

[Mike Carruthers]

And so when it gets into my phone and it gets into my car and it's raining down all these things, and then Apple, for example, will take that information and build on top of it and give you your, the estimated time of your trip and everything. Is Apple, is anybody paying the government to use GPS or it's just the taxpayer dollars?

[Katherine Dunn]

Yeah, it's taxpayer dollars.

[Mike Carruthers]

Wow, that's nice of us.

[Katherine Dunn]

It's really nice if you think about how many industries are built on the back of this. Yeah, well.

[Mike Carruthers]

And how many industries have been destroyed by it. I mean, the map business is pretty much dead. And that whole part of your brain where you used to have this sense of direction and kind of have to know where you're going, you don't have to know that anymore.

[Katherine Dunn]

Yeah. And if you think about a lot of jobs have really been transformed by this as well. If you think about surveyors, that's a job that has changed unimaginably since the invention of gps. And in fact, surveyors were very, very early adopters of GPS because it immediately cut down their work time. So that was sort of fundamental to changing the way that job was done. But yeah, it's, it's interesting Too because the US government also realized in the late 90s that whole industries were being refined or built on top of this product. And at that point actually they went and they spent several years going around the world promoting GPS and getting other countries to adopt it. So you know, it was a, it was a tool of power as well for whole country's civil infrastructure, their airports, their energy grids, all these things to, to become actually very dependent on this system.

[Mike Carruthers]

Yeah, I suspect maybe because it's free and it's always been free, that GPS kind of slid under the radar and kind of crept into our lives. We didn't make a big thing out of it because we didn't have to pay for it. And yet look at how dependent we are on it now. It's quite a story. I've been talking to Katherine Dunn, she is author of the book Little Blue How GPS Shaped the Modern World. And there's a link to her book in the show notes. Great to have you. Thanks, Katherine.

[Katherine Dunn]

Oh, thanks so much, Mike. I appreciate it. Thanks for interviewing me. So good, so good, so good.

[Mike Carruthers]

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[Katherine Dunn]

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[Mike Carruthers]

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Have you ever gone to the doctor with a physical symptom and the doctor couldn't explain it? Maybe chronic pain or fatigue, stomach problems or something else that was clearly real to you, yet every test came back normal? It's a frustrating experience that leaves many people wondering if they're just imagining it. And yet, medically unexplained symptoms account for a surprisingly large percentage of primary care visits. And when no clear cause can be found, patients often hear some version of, well, maybe it's just stress, or maybe it's all in your head. But what if that conclusion is wrong? According to my guest, Dr. Susan Trackman, many mysterious symptoms are very real physical experiences created through a powerful connection between the brain and the body that science is only beginning to fully understand. Understanding that connection can be the key to finally making sense of symptoms that seem to make no sense. Dr. Trackman is a specialist in psychosomatic medicine and author of the popular Psychology Today blog, It's not just in youn Head. And she's author of the book it's not just in your Head. Hi, Susan. Welcome.

[Dr. Susan Trachman]

Thank you, Mike. I really appreciate the invitation.

[Mike Carruthers]

You know, I guess it just doesn't seem intuitive that when you have a physical problem, to think that it has something to do with what's going on in your brain. Because a physical problem is a physical problem and therefore should have a physical solution. Which is why I imagine people have trouble buying this idea of a brain body connection.

[Dr. Susan Trachman]

Sometimes what we do know, and I could say to my patients, if I cut off your head, could you function? And of course, they look at me like, you know, cross eyed. And I of course not. So I think rather than looking at the brain and the body as two separate entities, it makes sense to look at them as being connected, because, in fact, they are. So if you think about the brain as a big computer, computer has all these USB ports, and they're connected to various organs in the body. And so communication flows in both directions, from the computer, the brain, out to the organs and back in turn to send information back to the brain. So that whatever is going on in your brain is going to affect various organ systems and vice versa. A classic example is the brain gut connection, which we hear a lot about now, because the brain and the gut are actually derived from the same embryonic material, and they communicate constantly. There's a big nerve that runs between the brain and the gut called the vagus nerve. And so whatever's going on in the brain is going to affect the gut. And they're almost like besties who are texting all the time. So if the brain's like, ooh, we're anxious. The gut's going to be like, yeah, we really are. I think we need to do something about that. And so then people develop symptoms like diarrhea or cramps. So we know that. And in fact, whatever is going on in the brain will affect other organ systems. For example, if your brain is stressed, it's going to impact your cardiovascular system, and you may develop hypertension. The American Heart association has identified stress as an independent risk factor for heart disease, and that is the case for many other organ systems, including other categories of illness, for example, autoimmune disorders.

[Mike Carruthers]

So what I'm curious about, though, is you just gave two good examples of how stress in your mind can cause problems with your cardiovascular system, or other things in your mind can set off your stomach and you get symptoms there. But not everything going on in my brain is causing symptoms. So why is that?

[Dr. Susan Trachman]

Well, something's happening, but you're not developing symptoms. So you're lucky. It's the folks who do develop symptoms and unfortunately are categorized in a group called, we call it musplained symptoms, who go from doctor to doctor trying to arrive at a diagnosis. And when the physician cannot come up with a diagnosis, using usual physical exam, laboratory studies, and, for example, even kind of radiographs, they might say to the patient, we really can't find anything wrong with you. It's all in your head. Go see a psychiatrist, which is how they end up in my office. And oftentimes I can listen to what's going on and arrive at a different diagnosis, because I do consider not just the target organ, but what else might be going on. For example, their psychological state at the time and also their environment. I mean, your environment very much impacts your physical health.

[Mike Carruthers]

So then it is in those cases it is in your head because that's where the problem is starting.

[Dr. Susan Trachman]

You're absolutely right. And when patients will come to my office and say, you know, my Dr. X told me it's all in my head, well, what I'll say is, well, it is because your brain's in your head and your brain is your master computer and your brain is sending signals to your other target organs which may be causing your symptoms, but may not be picked up by a very well meaning physician who's not considering the other possibilities.

[Mike Carruthers]

My sense is that when people say it's all in your head, what they're really saying is it's nothing.

[Dr. Susan Trachman]

Correct. And you can imagine how that would be very dismissive or demeaning to an individual who's trying to arrive at a diagnosis for their symptoms that are causing them real distress.

[Mike Carruthers]

But how often does this happen? How often do people present with real symptoms and, and it turns out it is in their head. Is it one out of 100? One out of a million? I mean, give me a sense.

[Dr. Susan Trachman]

Sure, that's a great question. 40% of visits to a primary care doctor are for general symptoms such as headache, fatigue, difficulty sleeping, shortness of breath would be another one. And in only 25% of those cases can a, quote, biological diagnosis be found based upon the usual physical exam, laboratory studies, radiographs. But there's lots of diagnoses that take a bit more investigation. And so I like to think of myself as a medical detective because I think about other factors that may be influencing the individual at the time.

[Mike Carruthers]

And those factors might be things like what?

[Dr. Susan Trachman]

Workplace stress, stress at home, a toxic environment, an environment in which they're exposed to secondhand smoke and they suddenly develop difficulty breathing and they go to a pulmonologist and the pulmonologist will do a chest X ray and do lab studies and listen to their lungs and they'll like. And we don't see anything. And yet the fact that they're being constantly exposed to toxins from their workplace can be actually causing some of the difficulty with their breathing. You know, some of the other factors that fall into the category of toxic environment would be, you know, chemical exposures, mold, undetected mold. And these things can cause all kinds of physical symptoms that may not be readily apparent to even a specialist. For example, toxic mold exposure can cause things like skin disorders, which a well meaning dermatologist may not pick up, even though they're looking for things that they can treat. And I think part of the reason is that in medicine we have become so specialized and so siloed that if you go see someone who specializes in, in cardiology, they're going to, well, meaning, try to find something wrong with your and if they can't, they're going to be like, we don't really see anything wrong, wrong. Maybe you should go see Dr. X and they'll be referred to a different specialist and that specialist again, they're going to try to find something they can find.

[Mike Carruthers]

What's your sense about how big a problem is this? That's what I really want to try to Understand is this. 50% of doctor visits. Is this 1/10 of 1% of doctor visits. How often does this happen?

[Dr. Susan Trachman]

There's about 80 million people in this country who are diagnosed with what are called medically unexplained symptoms. That's a lot of people. Many of them do not come to the attention of someone who can take a look at that. As I said, 25% of those who go see primary care doctors, they're not going to come up with a diagnosis. And even among specialists, it's not a whole lot better. So it's a cost in terms of one's self doubt, meaning if doctors are telling you there's nothing wrong with you but you know you have physical symptoms, it's self doubt. So it can impact you psychologically. It has a tremendous impact on work performance because there's a great amount of time spent away from work to try to diagnose these issues and try to find a provider who can come up with them. And in terms of the cost of the healthcare system, if you get referred to doctor, doctor, doctor and sometimes procedures that are not necessary, it's a tremendous cost for the medical care.

[Mike Carruthers]

When it is a psychological problem or a social problem, does often fixing the social problem or the psychological problem fix the physical problem? And, and how do you, how would you even know or tell?

[Dr. Susan Trachman]

Yeah, again, these are really great questions. So I'll give you an example. I see a lot of folks who referred from gastroenterologists who come to my office with a diagnosis called irritable bowel syndrome. And it's kind of a nonspecific term of people who are having, you know, alternating difficulties with diarrhea and constipation. But oftentimes the underlying issue with IBS is an anxiety disorder. And if you treat the anxiety disorder, their gastrointestinal symptoms improve dramatically. So how do I know? I know because I take a complete history, I find out what's happening in their life, I find out what's happened in their past life. There's a significant percentage of individuals who present with GI symptoms who have a past history of trauma or neglect. And so, you know, looking at these things and arriving at a more broad based approach to coming up with a diagnosis, yes, I actually can improve their underlying physical symptoms. Same thing, for example, with someone who comes in with an autoimmune disorder. Folks with autoimmune disorders have real physical symptoms. Their symptoms are based on the fact that their immune system, which is supposed to protect us from invaders, so to speak, overreact. And instead of just addressing an invader or an injury, it begins to attack one's own healthy tissues. We know from all the data that's out there that stress is a major factor in worsening symptoms of autoimmune disorders, because stress causes inflammation and inflammation is linked to many disorders, including autoimmune disorders. And if you can find ways of reducing the stress in their life, either through medication or psychotherapy, their autoimmune symptoms improve. It's not going to cure the underlying cause, but it can dramatically decrease their symptoms so that they become more functional and can actually use less medication that's prescribed by their rheumatologist, for example.

[Mike Carruthers]

So I want to understand something about pain. Can your brain create pain or it just makes pain feel worse? If you have real physical pain, generally

[Dr. Susan Trachman]

people don't imagine that they have pain. Generally there is some type of real reason I stubbed my toe, I have a bad tooth, you know, my head hurts. Usually they are real. But the way one interprets the physical sensation can impact the course of how this may progress or be treated. Here's an example of how people may perceive pain in a different way. I stubbed my toe. Ow, you silly, whatever you want to call yourself, you really shouldn't have done that. That's dumb. And you get angry at yourself versus someone has a history of breast cancer. They've had surgery for the breast cancer and hopefully they're in remission. Six months later, they end up doing some exercise and they pull a muscle and they have pain in the area of their scar. The question it may be, it won't be something like, oh, you silly, you did exercise and you exacerbated the pain in that muscle. It's oh my God, I hope the cancer hasn't come back. So it's the interpretation of the pain that may be very different. And the way people who now specialize in that area look at pain. And management of pain very much encompasses one psychological state. If you're depressed, your pain's going to feel worse, and if you're not depressed, you're still going to have pain, but it may not be as bad.

[Mike Carruthers]

What do you recommend, though, to people who don't know who you are until now? If I've got a doctor telling me we can't find anything, this really hurts, who do I call? What do I do again?

[Dr. Susan Trachman]

That's a very good question. I'm glad you asked it. I think that people in general know themselves and their bodies better than any doctor. Yeah, we go to school for a long time and we specialize and we think we're really smart, and hopefully we are. But I think that in general, patients know their bodies better than anybody. And if you're being told by a physician or a provider, there's nothing wrong with you, stop worrying about it. I had one patient whose doctor said, go read a book, which was absurd, right? I mean, it's good to read a book, but it had nothing to do with why her blood pressure was elevated. You have to look at reviews. In other words, if one doctor's telling you this and you don't appreciate what they're telling you because you know there's something wrong with you, you don't have to go back to that doctor. You know, patients are paying our salaries and we deserve to do the best we can. And if you as a patient are not getting the answer that you want, you don't necessarily have to go back to that provider. So what I like to say to patients is, you wouldn't hire a plumber without looking at their reviews. Right. There are plenty of sites now available where you can review patients reviews of physicians and their qualifications. And we have lots of resources now that we didn't used to have. Make sure that when you do go to a physician, because time is limited, write down your questions, write down your concerns. If a doctor tell or provider says we can't find anything, it is reasonable to ask, are there other procedures or tests that we might do that would help us? If the answer to that is no, again, very reasonable to ask the question, is there a specialist that you might consider referring me to who you think might look in a different direction?

[Mike Carruthers]

Are there things people can do themselves? Must they always seek out a doctor, or are there things they can do at home?

[Dr. Susan Trachman]

There are lots of things that you can do. So without getting into a whole lot of biology, there is A part of your sympathetic nervous system called your parasympathetic nervous system. And that's the part of our sympathetic. A part of our nervous system that helps us calm down and regulate. And there are things we can do to stimulate that part of our nervous system, such as exercise. One of the best things you can do to reduce stress. There's a quote from a Cleveland Clinic specialist in gastroenterology that says the best thing you can do for gastrointestinal symptoms is exercise. Adequate sleep. I think people really underrate the importance of a good night's sleep. If you don't sleep well, it causes all kinds of problems, including increased inflammation. Eat a healthy diet. And when I say diet, I don't mean you should go on a diet to lose weight. I mean there are foods that you can eat that can improve your mental health and physical health and actually decrease inflammation in your body. And finally, social outlets, if you have healthy social relationships. That has also been shown to help us live longer, decrease chronic illness and decrease stress.

[Mike Carruthers]

Well, this is very enlightening for people who have had problems and been told, you know, we can't find anything, or, you know, maybe it's stress. And it's all very vague. And there's really something to this that I think is important for people to understand. My guest has been Dr. Susan Trachman. She is a specialist in psychosomatic medicine and and author of the book It's Not Just in youn Head. And there's a link to her book at Amazon in the show notes. Great, great. Susan, thank you for being here.

[Dr. Susan Trachman]

I very much appreciate you having me.

[Mike Carruthers]

You ever notice when you watch professional tennis or you go to a gym and watch somebody lift weights, you often hear a lot of grunting? It sounds a little weird, and if you're standing nearby, it's hard not to roll your eyes or. But the fact is, grunting may actually help. Research has found that making a forceful sound while exerting yourself can increase strength and power. In one study, people generated significantly more grip strength when they grunted than when they stayed silent. The secret isn't the noise itself. It's what the noise does. Grunting usually comes with a forceful exhale that helps tighten your core, stabilize your body, and recruit more muscle power. In other words, that strange sound may be your body's built in performance enhancer. So the next time you hear somebody grunting at a gym, remember, it may sound weird, but there's a good chance those people are actually getting stronger because of it. And that is something you should know. Hey, I would really appreciate it if you would tell somebody about this podcast. Since you've just listened to a whole episode, you have a pretty good sense of what it's about. You could tell somebody and get them to listen and then we get another listener. And in this business, every listener counts. I'm Mike Carruthers. Thanks for listening today to something you should know.

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