How tech will (and won't) replace your doctor | Zack Abbott and Dhruv Khullar

0:02You're listening to TED Talks Daily, where we bring you new ideas to spark your curiosity every day. I'm your host, Elise Hugh. We're back with the next episode of our original series, TED Intersections, which features unscripted conversations between experts navigating the ideas shaping our world. There's more health advice out there than ever before, and no easy way to tell what's actually worth your time. From biotech breakthroughs to smarter cancer screening, doctor and writer Dhruv Kular and microbiologist Zach Abbott sit down to examine what happens when science can change who we are, including the potential of re-engineering the human body and what medicine might look like in 20 years.

0:46We're also losing the ability to feel our bodies, to understand subjectively what it means to be in good health. And do I have energy today? Am I feeling unsettled? What does it mean to thrive? And so I think that instead of layering on more metrics, which have a place, the most important metric is really this qualitative sense of, do I feel healthy today? Dhruv and Zach get into gene editing, AI in the doctor's office, why our grocery store tomatoes taste like water, and the strange, powerful world living inside our guts. We are really a walking ecosystem. And what's even more interesting is that, unlike our human cells, this bacterial community is constantly changing.

1:27It's very plastic and dynamic. And so it's not surprising that it has a huge impact on every aspect of our health. Throughout the conversation, they keep circling the same idea, that when science can change who we are, the hardest questions aren't about what we can do to stay healthy, but what we should do. This episode was made possible with the support of Z-Biotics. That's coming up right after a short break.

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4:27And now our TED conversation of the day. It is really hard to kind of get credible information out there that's also compelling when you're competing in a world where there's so much, it's so easy to generate content that is compelling that it is not accurate. Yeah, I mean, there's so many ways to be wrong and there's only a few ways to be right. Right. And so, you know, just if you do the math, it's like if you say something, it's probably going to be wrong. Yes. Unless you take a lot of steps to figure out if it's actually true. True or not.

5:10All right. Remember to go first? Let's do it. All right. Let's get into it. So what is a health metric you wish people will focus on more? Is it too cheeky to say no metric? So I think that we are inundated with health metrics. Some of that is to the good. I'm a doctor. A lot of what I'm focused on is metrics and quantification and how do we get people's cholesterol level to the right number. But I think we're also losing the ability to feel our bodies, to understand subjectively what it means to be in good health. And do I have energy today? Am I feeling unsettled? What does it mean to thrive?

5:46And so I think that instead of layering on more metrics, which have a place, the most important metric is really this qualitative sense of do I feel healthy today? We try to quantify things, put a number on it, and that makes decisions easier, right? But the reality is that everybody's biology is so different, and so those numbers are sort of indicative. But I agree with you that there's a lot of behaviors and things that I think that probably make a lot of sense, for people to spend more time on it. For myself as a microbiologist, my answer to this is always the microbiome, right? But even there, there's not a number or a metric that you can track.

6:22You go out and you get microbiome sequenced, you get that information back, like what do you do with that? We don't have a good answer for what to do next, even though we know it's so important and so central to our health. And so honestly, the answer I give is just eat more fiber. You're almost assuredly not getting enough fiber. 95 % of Americans don't get enough fiber. Totally. And for some people, it can be motivating to have a number. So if someone says, walk 10 ,000 steps, maybe that takes someone and gives them a real tangible goal to walk towards. But I also think there's a problem when people have to look at their sleep tracker to figure out whether they feel well-rested.

6:55You shouldn't have to wake up and be like, how did I sleep last night? That should be something that people can get from kind of being in touch with their own bodies. And so I think this push towards quantification needs to be paired with a vocabulary around how do I think I'm feeling today and what does it mean to live a good life? I love that point. It's like, it's so true. My whole life evaluated my sleep based on how I feel. And now it's like, oh, I feel like a good sleep. And I look at my health tracker and I'm like, oh, wait, was it not? Do I feel tired? Like I'm trying to like convince myself, you know, so that is a really interesting point.

7:26What is something that seems radical in healthcare now that will seem ordinary 20 years from now? I love this question. I think, honestly, it's genetic engineering. Recently, a person with sickle cell anemia, we cured that. I wasn't part of it. But, you know, the medical community cured that by using genetic engineering. And I think that is an amazing accomplishment and an amazing innovation and an amazing improvement. I think that people get a little worried about when they hear, like, oh, we're going to genetically engineer. So what does that make us not human anymore because we're changing our genes?

8:00The reality is that our genes are changing all the time. And we're changing them all the time, right? Mutations are normal. The things we're breathing in, the things we're eating, those are all causing changes in our DNA. It happens all the time. And then from that, we get diseases. And so this idea that now we understand better what some of those mutations and what they mean and the fact that we go in and correct them, I think, is a positive progression that we have for human health, right? Like you imagine somebody born with Huntington disease and, you know, by the age of 10, they might know that they are going to die of this like terrible genetic disease that you could just alter back to the normal allele and have them live a long, healthy life.

8:33And so I think I think now this feels very, very radical and very crazy and not say that, you know, I think people think of like designer babies. There's a lot of distance between nothing and that endpoint. Right. There's all these things we can do, like for kind of simple improvements of health that I think will seem I don't know if it's 20 years, but will seem, I think, normal. Yeah, I love that. And I think CRISPR-related genetic technologies, they are the future, and they're going to have a totally transformative impact. And they already have a transformative impact, as you're saying, on certain diseases.

9:02Another really powerful technology, which is, of course, artificial intelligence. And I think a lot about the delivery of health care and how in 20 years, I think a lot of the routine types of care that we get today will be delivered mostly by machines. So if you have a UTI, if you sprained your ankle and needed, you know, x-ray, certain other types of things that are preventative and routine care, I think a lot of that is going to happen just with computers and algorithms. I still think a lot of the more complicated, human, difficult decisions that we have to make, there's going to be a central role for doctors and nurses and other types of clinicians who are augmented with AI.

9:42But I do think that there'll be kind of two streams in the way that we get care. One is this kind of more transactional stream. I mean, not everyone wants, you know, the human touch when they're picking up their, like, you know, Cipro for their UTI. It's fine if that's transactional. But if you're diagnosed with cancer or your parent has advanced heart failure or dementia, and there's a lot of uncertainty and a lot of integration that's needed of a person's values and preferences with the science and the evidence, That's where I think humans will still play a really central role, not just in 20 years, but in 50 years.

10:17Yeah, I think that last point really sparks a thought for me, which is that a part of the care is the human interaction. And like you mentioned, sort of like palliative care or dementia or things like that, right? Where the interacting with this trusted person, right, who's like looking into you in the eye and taking care of you is a really important part that you basically can't replicate, right? But I recently read a study where they showed that depending on the branch of medicine and the situation, there were times when literally AI alone was better than AI plus a human or a human alone. And then, of course, there were areas where one of those other two cases was the best.

10:51And so I think that will always be a dynamic situation. But ultimately, AI is a tool. And with all tools that humanity has leveraged, it just allows us to kind of level up what we can do next. And so we will never become obsolete. I think that's what people worry about. It's just like we'll focus our attention on the things that matter. All right. You ready for the next one? Yeah, let's do it. All right. What do you think should be fair game in biology or medicine that people right now are reluctant about? I think a lot about how poorly we do in detecting and treating cancer at an early stage.

11:25And I think there's a tremendous appetite from the public to go beyond the types of screening that we have today. Look, there are some people who don't get the colonoscopies and mammographies and pap smears and all those things that we have that are very effective at picking up cancer at an early stage. But there's a lot of people who say, look, that's three or five or even eight cancers that we can pick up. But there are hundreds of types of cancers that people are at risk for. And how do we detect those at an earlier stage? And so there's a real movement. I mean, you think about things like liquid biopsies, where people are taking blood and trying to see early signs of malignancies that are circulating in the bloodstream.

12:03Or even things like full-body MRIs, which I think right now don't have the evidence to recommend to the general population. The average person should not be going out and getting, you know, annual MRIs. But I think in the future, as technology improves, as these tests get better at picking up the true positives from the false positives, as our imaging improves, I could see a future in which we have a radically different cancer detection paradigm where actually we're able to catch these cancers much earlier and intervene in a stage that people can go on to live basically a normal life expectancy.

12:40What resonates with me in that is this idea of more proactivity, right? Like being ahead of things rather than being reactive. And diagnostics and our ability to leverage new technology that used to be too expensive or too impractical, that more and more can become low-hanging fruit, can be things you can do on a regular routine basis. When I think about what people are reluctant about, it's interesting to me that in much of our lives, we embrace technology as a way of advancing a field and bettering our lives in some way. When we get into a car, we want the most technologically advanced car. When we buy a cell phone, we want the most technologically advanced cell phone, right?

13:16That technology, that advancement is good. And I think that the narrative sort of flips a little bit when you look at, like, the food system and you look at, like, the health system. Sometimes people are sort of reluctant or wary around, like, biotechnology entering the food system. But the reality of that is, is that we can make deliberate decisions about our food and we can engineer our food to be better. Say a little bit more about that. I mean, about using biotechnology to improve the food supply. When they think about technology entering the food space, they think about ultra-processed food.

13:44That's such a great call out. You're right. That like a lot of what, part of the reason why there is a lot of mistrust in technology is that the technology that is in our food system is not always to our benefit. And so I agree that that engineering or that biotechnology should be being applied in ways that can actually benefit the end user's health rather than benefit, you know, like making more addicted to the product, which is a lot of times the case. And so as an example, you know, we've done a lot of inefficient genetic engineering over the last several hundred years of like of a lot of the common crops we eat today, right?

14:17Like tomatoes and things, right? We do a lot of crossbreeding of them. and to get this tomato that's like bright and red and looks wonderful and looks great on the shelf. And then we eat it and it tastes like water. And people are like, oh, like this is terrible, right? And the reality is that like through crossbreeding, we actually bred out things that provide a lot of the micronutrients that tomatoes traditionally have, like these phytochemicals and things. In an attempt to make it look red and nice, accidentally through an inefficient form of genetic engineering through crossbreeding, We also have silenced genes that allow the fruit to keep creating sugars and polyphenols once it's been picked off the vine.

14:51You can imagine you could use genetic engineering to go back and just turn that gene back on, right? And then now you have a tomato that looks beautiful and it's delicious and people buy it. And then now they're eating more fruits and vegetables, which is important, right? And it also has more nutrients, more of the things that we know are good for us. The reality is that the technology is a technology, it's a tool. And what we apply it to do, I think, is what's important. And so there is a lot of kind of like this push and pull against that. But I do think that one of the greatest things we can do for human health is be more deliberate about how we're evolving our food system.

15:21It's so funny. I've gotten so used to beautiful-looking, tasteless fruit and vegetables. You know, the other day I was eating a tomato and it was so juicy. I told my wife, like, why is there so much juice in this tomato? And she's like, that's what tomatoes are supposed to be like, not these like cardboard, you know, imprints that you've been eating. And so, you know, what you say like resonates so strongly.

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17:29What do people get wrong about the work you do? You know, I'm a microbiologist and I, you know, we genetically engineer probiotic bacteria. And the goal is for that to make that for products for people to purchase. And I think that the thing that everybody assumes that is wrong is that consumers won't do not want genetic engineering. They don't want GMOs. And the reality is that they don't want the GMOs that they've currently been given. Right. Because there is no benefit to them. Right. The people who are benefiting are different than the people who are taking on the risk. So if you walk into the grocery store and you have a choice between non-GMO corn and GMO corn, there is no benefit to you to buy the GMO corn.

18:09The benefit was for the seed producer or the farmer. And so you say, well, I don't know much about GMOs, but I've heard that they have some risk or some problem or they might be bad. So, of course, I'm going to buy the non-GMO because there's all risk and no reward. Right. And so the logical fallacy that happens from that is that then people assume that because they made that decision, that they will reject all GMOs no matter what they do, no matter what they are. The reality is that people choose things based on risk and benefit all the time. Right. And so we get into our cars every day. And it's an incredibly risky behavior.

18:42Right. Like one of the most likely ways for you to get injured or die is driving a car. But we do it because we say, well, that risk is worth the benefit. Right. And so, of course, I'm going to I'm going to I'm going to make that choice. and most people do. I think the same is true with genetic engineering and GMOs, is that if you use genetic engineering responsibly and build something that creates a benefit for the end user, then that's a much different calculus. You say, okay, well, I don't know, maybe there's some risk with the GMO. I'm not sure, I'm not educated on this, but I know that I want this benefit, and so I'm willing to do that.

19:11Obviously, as somebody who uses genetic engineering, I believe we can make products that don't create risk. I think that is incumbent upon the technologists and the inventors to use the technology responsibly, But ultimately, at the end of the day, what people get wrong is this assumption that, like, we will always throw the baby out with the bathwater. And that's just not true, right? Like, you make products that people want. You do it responsibly. You do it transparently. You align with their values. You give them a benefit that they couldn't get any other way. And you tie that to the technology.

19:36And we've seen, you know, 15 million times that people have chosen that technology. Yeah. That idea of, you know, risk and benefit resonates a lot. And I think it ties into, you know, my role. You know, I work as a doctor and as a writer. And as a doctor, I think people often have the sense that you are taking this huge body of scientific knowledge and just applying it to the person in front of you and coming up with a diagnosis and a treatment. And that's great when it happens. But more often what happens is you're operating in a type of gray zone where there isn't a perfect clinical trial. Right.

20:09And there isn't, you know, the exact answer that you want. And you're trying to walk people through the uncertainty. And you're trying to weigh the risks and the benefits and the tradeoffs and come up with a solution for someone that works for them. And so I think there's this kind of popular narrative of a doctor as having the right answer and giving it out, and then things get better or they don't. But a lot of what you're doing is actually managing this whole big morass of gray area where you're trying to figure out what's important to someone and what types of risks are worth taking for some type of benefit.

20:46And then I think on the writing side, you know, a lot of what I'm writing about is complicated scientific issues, sometimes kind of controversial issues as well. And particularly in the modern media environment, I think people feel like you're trying to persuade or convince people or express a particular point of view. And again, sometimes I am trying to project a particular point of view. But more often than not, I'm just trying to figure out what the heck is going on. You know, the world is so complicated. Things are moving so fast that I think there's a lot of value in just trying to understand reality and put it out there clearly and let people make their own decisions and draw their own conclusions about what is happening.

21:31And so more often than not, it's an exercise in trying to see things as clearly as I can and put them into writing so that people can take from that set of facts what they will. And so I think, you know, not everything is kind of expression of a particular agenda or point of view. A lot of it is just, here's the facts as clear as I can see them. As a scientist, that resonates immensely, right? I think similarly, people assume that there's like an answer, right? And especially when it comes to something as complicated as biology and human biology, right? Like, I'm sure as you encounter as a doctor all the time, that there's a vast swath of realities.

22:11and everything is integrated. There's very few things that are black and white, right? Because your individual biology is going to affect your outcome in a lot of ways. And it's the same with science. It's like in these conditions, in this situation, right? But there's so few black and whites. Everything is in the middle. And I think that people want the answer. And you're like, well, this is the heavily caveated answer based on how we set up the experiment, right? And that's not interesting or exciting. And so you sort of get these black and whites, and then people extrapolate that well beyond kind of like your own narrative.

22:36And, you know, I think it's very similar. because as a scientist, you are a writer as well. That's the challenge is that I feel in a way science and medicine is sometimes at a rhetorical disadvantage. Yes. How the evidence that we have is applicable in this case, but not in that case, and we don't want to draw broad conclusions. On the other side, you have a set of people who don't care about any of that. Right, just want to drop the hammer. Some kernel of truth and just run with it. So the advantage I think we have is that often the facts are on our side and facts tend to ultimately prove out to do well in the long run.

23:10But it's a tremendously difficult communication challenge because scientists, what they're often doing is just laying out the studies and the facts as they can see it with all the relevant caveats. And that's not always the case for influencers on social media, let's say. Right. No, absolutely. I think that you're exactly right. We hold ourselves to a different standard, right, of like saying what's accurate, which is usually less provocative, less interesting. And so, right, you take like the sliver of like, well, in these situations, this happened. And then you kind of have a bunch of people make it more interesting by like making it a hard truth.

23:42And then you go way, you know, pendulum swings, right? And then it turns out that, you know, this isn't just some magical cure-all for everything. And then the pendulum swings all the way back to like, oh, you know. So it is really hard to kind of get credible information out there that's also compelling when you're competing in a world where there's so much. It's so easy to generate content that is compelling that is not accurate. Yeah. I mean, there's so many ways to be wrong, and there's only a few ways to be right. Right. And so, you know, just if you do the math, it's like if you say something, it's probably going to be wrong, unless you take a lot of steps to figure out if it's actually true or not.

24:17If science can change how our minds and bodies work, what should stay off limits? That's a very good question. I think we were talking about gene editing before and the tremendous promise of gene editing for so many people, everything from sickle cell disease to cardiovascular disease and beyond. And one thing that all those therapies currently have in common is that they edit somatic cells, right? Cells that are skin cells or brain cells or organ cells, basically every cell in your body that's not a reproductive cell. I think some people have talked about editing germline cells. And those are cells that go on, of course, to pass on traits to the next generation and potentially propagate throughout the species.

25:02And I think that most geneticists and ethicists believe strongly that we should not be doing. And currently, I think we're not doing that in humans. And I think that should remain an area where we're very cautious about. Because you don't know the unintended consequences when you put out some new genetic technology that makes its way into the next generation. And those next generations have not consented to have their genes changed in X, Y, Z way. And I think, relatedly, we should be kind of cautious about the idea that there are quick fixes, genetic or otherwise, to problems of the human condition.

25:39And so, if you think about, you know, a lot of people, let's say, are struggling with anxiety. Can we find a set of genes and edit them to reduce anxiety in the population? I mean, that might sound like a good thing. On the other hand, anxiety and worry and preoccupation and fastidiousness, these are all reasons that you might study for an exam instead of going out and partying the night before something that is really important to you. Or ego. We have problems with narcissism. Maybe we want to tone down people's ego, which in some cases is probably good. In other cases, it might mean that people aren't as striving as they were before.

26:16They're not as innovative. They're not trying to make a name for themselves. All things that have sometimes very positive downstream consequences. And so I think my answer would focus on editing, restrictions on editing germline cells that are then passed on to the next generation. Yeah, it's interesting. I'll push back. I'll take a slightly different approach to that. But I hear where you're going with that. I think kind of what we were talking about in the last question, the idea of I think it's very hard to draw black and white. It's that everything, when you zoom in enough, has a little bit of gray in it.

26:48And so I think that this idea of what should stay off limits, it's very hard to kind of draw a line now that you're sure will still make sense 20 years from now. And I think that there are things on the extreme ends that we could probably all agree on that are probably silly to even talk about. So not interesting answers. But even like you said, journal line mutations, I'm not saying that I'm advocating that we definitely should do that. But I think with a journal line mutation, I think if you zoomed in enough, you find the gray areas there too. I mentioned earlier Huntington, this idea that what if we could remove that?

27:19This is a mutation that will shorten this person's life, totally in a very simple change could make that better. Your point like there's a lot of unknowns, absolutely. That's true with any technology. But ultimately, all technologies come with unknowns and then as we work through them, we are comfortable with those unknowns and we make those trade-offs, then at some point, we sometimes decide that that's okay. So I'm not saying for sure that that's what happened during my mutation. I'm not advocating passionately that we should be doing it. But I think that my take on this question is it's hard to say what should stay off limits.

27:49I would advocate more. What should be off limits is close-mindedness. Like, I think at the end of the day, that's not like we should embrace all possible technological advances. I mean, in all directions, we should be thinking about, like, as the inventors and as a technologist, we should be thinking about what are the impacts. We shouldn't just do something because we can, right? We should think about, like, what are the unknowns? What's the consent? What are the ethics of what we're doing? And that's not always the case. And so that needs to happen. But on the other side, I think the public and the skeptics should also maintain an open mind about, like, while something may sound scary or dangerous, like, when you think about, like, the cost of not doing it for somebody who is bearing a lot of risk because we can't apply the technology, right?

28:25Like, we can't sit in our town in New York and tell people in Florida, like, what they should be doing about their environment, right, ultimately. Like, they're the people bearing the risk of those things. And I think it's similar with genetics, right? That at the end of the day, it sounds scary to us, but then what about the person living with that disease?

28:45What is so special about the gut biome? This is an area of deep passion for me, of course. And I think it's probably not news to anybody that the gut microbiome is incredibly impactful on human health. There are as many bacterial cells as human cells in our bodies. And while all of our human cells have the same DNA, all these bacterial cells have the different DNA and so they're performing tens of thousands more functions than our own cells are performing. We are really a walking ecosystem. And what's even more interesting is that unlike our human cells, this bacterial community is constantly changing.

29:20It's very plastic and dynamic. And so it's not surprising that it has this huge impact on every aspect of our health. People have probably heard a lot of kind of like the gut-brain axis and this idea that like our bacteria are kind of like communicating directly with our brain. And that's true. I mean, literally the chemical language that our brain uses to talk between cells and neurotransmitters was taken from bacteria. Bacteria produce many of the neurotransmitters our brain do. And the challenge is that we don't right now understand much more than that, than that. It's really impactful, but it is such a complex system.

29:53And we're really just kind of scratching the surface. It seems like the gut microbiome is incredibly diverse, but also a very delicate balance. You my own work, I see if too much of the bad bacteria grow and you don't have enough of the good bacteria, you can have a devastating infection. If some of the bacteria that are in your gut, the millions and billions and trillions of them enter the bloodstream on the heart, that could be deadly. So there is this really interesting balance that's required inside the body in terms of the microbiome. But it seems like we haven't quite gotten to the stage where we can intervene based on this knowledge.

30:32And so where do we need to go to get to that place? Yeah, I think it's a very hard question to answer because even just like kind of pick out the good bacteria versus the bad, it's actually context dependent, right? Like we often have heard about bacteria like E. coli. It's this like, you know, it's a food pathogen, it makes you sick. You naturally have several strains of E. coli living in your gut and they're performing really important functions all the time. But then there are other strains that aren't so good. So like it's the strain level, but then it's also like the context, the other bacteria around that are counterbalancing it that are really important.

31:01They create this whole complex network and interplay. And so first thing we do is just learn more and learn, I think, more population level and network level effects of a highly dynamic and highly complex system, more complex than anything else we've ever examined. Basically, the more different types of bacteria you have in your gut and the more evenly they're distributed, the more functions you have at your disposal. It's basically you're building out a bigger toolbox. And so the way you support diversity is eating more fiber and not just the absolute amount of fiber, it's eating a diversity of different kinds of fiber, different bacteria like different types of fiber.

31:30So eating lots of different plants every day, getting from natural sources, right? It's not just like put a scoop of 20 grams of fiber in your smoothie and you're good to go. It's like really getting all those different types of branches and chains of fibers from all these different foods. For instance, I try to eat 20 different types of plant every day and 30 different types of plant every week as a way of supporting a diverse microbiome. You get a diverse microbiome and you do fiber fermentation in the gut, create short-chain fatty acids, which we know are beneficial. So that's the low-hanging fruit.

32:00Beyond that, I think we just have a lot of work to do to figure it out. Well, this was great, Zach. Thanks for taking the time. I really enjoyed this conversation. Drew, this was super great. I appreciate it. Lots of thought-provoking stuff.

32:12You were listening to a conversation between Zach Abbott and Drew Kular for our original series, TED Intersections. Visit TED.com to watch this conversation and others from the series. If you're curious about TED's curation, visit ted.com slash curation guidelines. And that's it for today. TED Talks Daily is a podcast from TED. This episode was fact-checked by the TED Research Team and produced and edited by our team, Martha Estefanos, Oliver Friedman, Lucy Little, Emma Taubner, and Tanzika Sungmarnivong. Additional support from Daniela Ballarezzo, Christopher Faze-Bogan, Valentina Bohanini, Banban Chang, Brian Green, and Lainey Lott.

32:53Learn more at podcasts.ted.com. I am Elise Hu. I'll be back tomorrow with a fresh idea for your feet. Thanks for listening.

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