The secrets to aging well with Zeke Emanuel

0:01This is TED Health, a podcast from TED, and I'm your host, Dr. Shoshana Ungerleiter. Lately, I've been thinking about how complicated health advice has become. I've talked about it on this show, too. It's interesting because at the end of the day, most of us just want to feel good in our bodies. We want to have good health as we age. We want to stay mentally sharp and enjoy our lives along the way. It's a pretty clear goal. But every day there seems to be a new headline telling us to eat this, avoid that, track more data, optimize harder. And it can start to feel like staying healthy is a full-time job, one that requires discipline, money, and constant vigilance.

0:43But what if the biggest drivers of long-term well-being were not extreme routines or expensive tools? What if, instead, the answer is a lot more doable? A handful of simple habits done consistently over time, with room for pleasure built in. To help us sort out the facts, I invited Dr. Zika Manuel to join me on the show. Dr. Manuel is an oncologist and bioethicist, a best-selling author, and one of the most influential voices in American health policy. He's currently Vice Provost for Global Initiatives at the University of Pennsylvania, and that's just one of the many impressive entries on his resume.

1:22He's helped shape everything from research ethics to national healthcare reform, advised multiple presidential administrations, and spent decades studying how health systems and individual choices affect how long and how well we live. His new book is called Eat Your Ice Cream, and its message cuts through a lot of modern wellness noise. In our conversation, Dr. Manuel explains why longevity should not be about chasing the longest possible life at all costs. Instead, he makes the case for maximizing years of good function, connection, and enjoyment. Because pleasures like ice cream sundaes can be part of a healthy life too.

2:04Things like movement, sleep, food, social ties, and mental engagement are key to a long and happy future, and none of them require perfection to make a meaningful difference. Then after the interview, stick around for a TED Ed lesson that takes us inside the science of aging itself. If we can't see age written clearly on the human body the way we can in trees or mileage on a car, how do scientists measure it? And what can those measurements really tell us about what healthy aging looks like? That's all ahead, but first my conversation with Dr. Zeke Emanuel. And before we dive in, a quick break to hear from our sponsors.

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5:39Now I want to welcome Dr. Zeke Emanuel to the show. It's a real privilege to have you here. Your work has truly shaped how so many of us think about medicine, ethics, and really what it means to live well. Well, thank you. Thank you. So you've spent your life moving between medicine, ethics, policy, and teaching. And when you step back and look at that whole arc, what question about how we live and care for one another has stayed with you the longest? When I was a freshman, there was a bird sanctuary with lots of trees down the hill from my college. And one winter day, I walked in to the bird sanctuary and found a log.

6:23I sat down on the log and I was thinking and I spent a lot of time there and a kind of epiphany I think is what others would call it came to me it's like look I'm on this planet for a very short time I want to make a difference and the difference I want to make is how can I make the world a better place for people to live in so that more people can have more fulfilling lives and it seems to me that upon reflection all these many years later, that's a very common motivation for a lot of people who we greatly admire. Here at the University of Pennsylvania, our founder is Ben Franklin, and I have a course on Ben Franklin on Coursera because he's just a remarkable, brilliant person.

7:09But mostly what makes Ben Franklin so amazing is that the key to his life is he always was wondering how he could be useful in his community, in his larger city, in the country of the United States, how you can make the world better for other people, I think is one of the most important motivations for wellness. This is something I think about a lot. And that sense of a through line, something persistent beneath all those roles feels really essential to understanding your work. And you've certainly changed and helped shape national conversations about health policy, yet you've also sat at bedsides with patients near the end of life.

7:54What do patients consistently understand about health and aging that our healthcare system still misunderstands? Well, our healthcare system doesn't do a great job about wellness. When we were passing the Affordable Care Act, politicians would say, you know, we've got a sick care system, not a healthcare care system? And the answer to that is yes, we do. And the main reason we do is because we pay for sick care. We don't pay for wellness and health. One of the big complaints of a lot of people is doctors almost never ask, well, how many friends do you have? How frequently do you talk to them? One of the most important things for wellness, they don't actually think is that important.

8:34Yes, they might talk about smoking. They might talk about alcohol, but lots of other stuff, they don't even scratch the surface of. Yeah. And I want to stay with the bedside for a moment just because that's, this is certainly an area that I care a lot about. And so as an oncologist, I suspect you've spent years listening to people talk about what matters most when time feels limited. What do patients say that surprises you or clinicians and how might our lives change if we were to normalize those conversations much earlier? Well, I think for a lot of patients, They know there's a family event that looms very large for them, whether it's a wedding or the birth of a first grandchild.

9:17And you see a lot of people struggling to figure out, can they go and have those events? And it's very important. But you also see people at the other end. They don't want to fight it. They've had a good life, and they often put it in this language, being tortured by chemotherapy is not how they want to end their life. My father is a great example of that. He was 92 when he was diagnosed with a very large brain tumor. He said, nope, not going to get additional treatment. Everyone came in, and he had 10 pretty good days visiting with everyone and died peacefully in his sleep. And so I think you see both of those elements where people are clear about what is important to them.

10:04And part of the role of a doctor is to figure out how to make what you've deemed important happen. My job is to make the best of the time they have. Some of them I can offer a cure. Some of them you're just not going to be able to cure. And so the issue is to try to make it as good as possible. It's been interesting to me to see how, for people facing a life-limiting illness, how clarifying that can be about your goals and your values. You know, people often ask me, why'd you go into oncology? And I said, well, it's so raw because people's values come to the surface. And it's a privilege to have that conversation.

10:45You get to know patients intimately in a way you can't in almost any other aspect of medicine. And it is a privilege to be there, but it's also, if you do it well, very helpful. One of the things you see, even in the patients who are cured of cancer, is they put away a lot of stuff that gummed up the works in life. Those meetings, not necessary. I'm not doing it more. And then they focus on the things which are really, really important to them, and they think important to the world. Yeah. Zeke, one of the things that we touch on this show and is certainly coming up quite a lot is this idea about longevity.

11:23And much of your work challenges the idea that longer life expectancy automatically means progress. So what should we be measuring instead if we truly cared about living well? That's a very sophisticated question. And let me just put it in perspective. The first thing to recognize is at the upper limit, you know, the people who are centenarians and supercentenarians We're getting more centenarians, but the amount of time people are living at the top end hasn't increased. So all these advances are not increasing the top end, which is why a lot of us think there's a sort of biological limit to the life expectancy.

12:02We are getting more people into the late 80s and 90s. What I think we should really focus on is getting past 75. And the fact of the matter is that we still have a lot of people in America who are dying, and not just America, by the way. Every developed country has a 20 to 30 or 40 percent of the population dies before 75. And our big challenge, very big challenge, is to get all those people up to live a full life. And we can stop worrying so much. And it's really the people who are dying at 50 or 45. and almost everyone these days knows someone like that because the cancer rate of people under 45 is going way up.

12:44So I think those are the conditions we really need to focus our attention on because someone dying at 40, that's a tragedy. They're probably half the age they should be and we've got to do a better job of preventing those deaths, especially kids' deaths. I mean, preventing kids' deaths and preventing illness that disrupts the normal development, that's what really motivated my father. as a pediatrician. So when we start talking about the sort of longevity movement and biohacking, I think that filters out into everyday folks and social media and the pressure shows up as this constant self-monitoring and optimization.

13:24Many people, including myself, right, as a physician, feel overwhelmed by conflicting health advice and this idea of constant optimizing my health Based on decades of research and clinical experience, what truly deserves our daily attention and what are we dramatically overcomplicating? Well, my book is all about don't obsess about this. Here are the simple things you can do and you don't have to worry about the latest fad. And I say this to people all the time when they ask me, well, you know, should I take this supplement or what about peptides or what about what's the diet you would recommend?

14:04And I said, listen, if something's going to be a home run, really make a difference to your life, like GLP-1s, you'll hear about it. Everyone will be talking about it. It'll become standard of care. If not everyone's talking about it, if it's just floating around on the ether of the Internet, you know, it's probably unsupported and not very valid. Or there may be a study that suggests it with a small number of people. and I wouldn't give it much stock and I wouldn't really spend a lot of mental capacity focusing on it. So what I like to say is the first important thing is, first chapter of my book is don't be a schmuck.

14:44Don't do stupid things that are high risk with not a lot of high reward. We know some of them like don't smoke, don't vape. We also know that, you know, take your vaccines, get your cancer screening tests. I have a long discussion of the PSA, which I actually don't recommend. And then there are some things which are really stupid. Base jumping, climbing Mount Everest, where the risks are mind-boggling hike. I mean, climbing Mount Everest, most people think, well, you know, you can go there as a tourist, pay$150 ,000. You know what? The risks of dying on Mount Everest are one in a hundred for all comers, including mountaineers and Sherpas.

15:22And if you're over 59 years of age, they're 1 in 25. What could be more stupid? Okay, just dumb. Don't do it. That's the first thing. We should all be aware that the most dangerous thing we regularly do is turn on the ignition of our car. The chance of dying over a lifetime are under 1 in 100 from driving. Okay, that's really high. So you have to balance things again. And we're all, none of us are stopping to drive. So we have to balance against that risk everything else. The other thing that I would put front and center is the second chapter, which is socialization. As I said at the start, one of the things that we don't think about is social interaction as a wellness activity.

16:13It is a wellness activity. There is literally a mountain of data. More than three million people have been followed assessing their social activities and their longevity. And it turns out that it's really, really important. I'll just give one study, the Health and Retirement Study, which is a big study of the U.S. government funds that tracks people over time, 20 ,000 people over 50, did a study where they looked at people's number of friends, number of close friends, how much time they spent together, the quality of the relationship, and then they followed people for eight years. And it turns Turns out people who had more close friends compared to people who didn't actually had 25 % lower risk of mortality in the next eight years.

16:58That is huge, huge decline. At the other end, there are these things called weak social interactions, people you might not know, people where you have some overlap but not a lot. Those turn out to be really important for daily life, happiness. And we think, oh, well, it's all in your head. You know, that's good psychologically. No, it's good physiologically. your body. Researchers have looked at genes in the UK biobank and, you know, it turns out that loneliness is associated with genes that actually regulate the immune response, overreaction of the immune response. More social interaction decreases your cortisol level, so it decreases your heart rate, your fight or flight stressors.

17:38So they have physiological impacts and we tend to ignore that. So both deep relationships cultivate your family, your close friends, but also cultivate casual relationships, whether it's with a barista, a cab driver, someone, your waitress, waiter. It helps you and it helps them. Yeah. Yeah, it's interesting. I'm a pretty extreme introvert, even though I'm talking to people all day long. So I've had to reframe this in my mind as this is a wellness practice, just like the two hours of walking or running I'm going to do this afternoon. I have to force myself to interact with other people for my health.

18:15Yeah, so Shoshana, it turns out that a professor at the University of Chicago, Nick Epley, has done great studies on this. And introverts, and about 25 to 30 % of the population is introverted, when they force themselves to be extroverted, actually are happier. And yes, they may be hesitant, more hesitant than extroverts, but it turns out it has this positive impact even on an introvert. So your experience is exactly the experience that people should do. Force yourself to be extroverted. It turns out to be good for you.

18:52We'll be right back with more of my interview after this quick break. This episode is brought to you by Peloton. There's a particular kind of joy that comes from a really good workout. When your body feels free, your mind clears, and you remember why movement matters. Peloton built the cross-training Tread Plus powered by Peloton IQ to help you find that feeling more consistently. Peloton IQ personalizes your workouts, plans your sessions, tracks them, corrects your form, and offers the kind of guidance that helps you unlock new versions of yourself over time. And because real fitness isn't just about running, the cross-training Tread Plus features a swivel screen that lets you move seamlessly from a treadmill run to strength training on the floor, one smooth spin, no break in momentum.

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20:44So I love the title of your new book, Eat Your Ice Cream, and congratulations on the New York Times bestseller list. I saw that. Well, thank you. Thank you. Why did you choose that phrase? And what does it capture about how you think people should balance their health and pleasure and probably responsibility and meaning over a lifetime. You point to the fact that it's unexpected for someone in wellness to say, eat your ice cream, indulge yourself a little bit. But part of the book is, look, we're here only for 75, 85, 90 years, right? You can't make wellness a lot of self-deprivation, self-denial.

21:23You're just not gonna continue if that is it. You have to do these wellness practices for decades and they have to be integrated into your life and you actually have to find them pleasurable. A scoop of ice cream is not going to mean you die five years earlier. It just isn't. And you should enjoy it. Everyone enjoys ice cream. You should enjoy that ice cream. I have a friend who his 9 p.m. nightcap is not whiskey or alcohol beverage, but it's a scoop of ice cream. That's great. Look, the wellness should be pleasurable. It should not be something that's onerous to you because you won't continue it.

22:00We all know that willpower fatigues. It's limiting. You can't do things by willpower over and over again, which is why the vast, vast majority of New Year's resolutions go out the window because people are just trying to force themselves and most people can't adhere to the diets because they're mostly about self-denial. You have to make it more about pleasure. And I think that's a message people want to hear. They want to understand that life can be pleasurable and healthy. A healthy life does not, should not, better not be one of continuous self-punishment. It's just not going to work. So sleep and movement and food and connection and curiosity, they sound simple-ish, but they're not equally accessible.

22:44And from an ethics and a policy standpoint, where should responsibility fall between individuals and society when it comes to making healthy lives possible. So I wrote this book first to make it very affordable for people to say, look, these are things you can cut out and you're not going to sacrifice, right? Supplements, you don't need to spend money on them. Sleeping pills, don't spend money on that melatonin or whatever. Buying a Fitbit or an Apple Watch or whatever, whoop. You don't need to do that to be well. Probably the place where cost is a big issue is in food. And that is an area where we can do better, but also society has to do better because our food ecosystem actually is a major part of the reason that we have such overweight and obesity-related illnesses like heart disease and stroke, kidney disease, wearing out of joints, hips, and knees requiring replacement.

23:46So we can do things like stop drinking sodas because they're 140 calories with absolutely no nutrition. We can do things like stop eating packaged cakes and cookies and pretzels and potato chips because, again, they're not nutritious and the proportion of calories has gone way up. So we can actually save ourselves money by eating better now. The problem is that eating better is expensive. fruits and vegetables are minimally subsidized by the government, but largely not compared to ultra-processed foods that we've made, you know, corn and soybean and wheat and rice cheap so that the big manufacturers like Cargill can turn them into ultra-processed foods or sell them to Kraft and other ultra-processed food makers.

24:35And that's the disconnect. So the system needs to improve thing. I also think the system needs to improve. We probably need to bring back home economics in school so that people know how to cook for themselves. We also need better school lunches for kids. A lot of that school lunch is simply a dumping ground for ultra processed food. Yeah. Well, I want to switch gears a little bit and ask you about a statement you made. You once said that you would be ready to die at age 75. And I think that made many people uncomfortable. What conversation were you actually hoping to start at that time? Oh, Shoshana, your questions are very sophisticated because you realize I didn't say I wanted to die.

25:17I said I would be ready to die and I wouldn't take life prolonging treatments. And that's a very important distinction. So, look, I know what hell looks like to me. hell to me is if my body's working great good physical shape the heart's still pumping great you know the blood vessels are good the kidneys good liver's great but my brain isn't great and I've got cognitive impairment and dementia that is hell I don't want to be remembered like that I'm not there if that is true and so when you look at the data and what's clear is the rate of dementia is sort of relatively low. There are some people who get early dementia and then shoots up at 75.

26:02And a lot more of people have cognitive impairment where they're not fully demented, but their brain isn't working as they want or normally. And that's what I am going to try to avoid. Because I know that what makes my life meaningful really has to do with how my brain is functioning and how well it functions. Being alive and demented is my view of hell. I don't want to be in that condition. And the essay was really, here's my philosophy. Now, what's your philosophy? I was challenging the reader not to adopt my philosophy. There are a lot of people. So a third of people, they just read the title, you know, Why I Want to Die at 75, which I didn't give it, but the editor did.

26:46A third of people say, oh, Dr. Emanuel, You know, you finally gave voice to what I have been thinking in my philosophy of life. Thank you so much. And to this day, get a lot of those responses. And then a third of people are like, wow, that's a challenging question. And it's making me think. And they're very uncomfortable with that. And I think those are the people I was trying to get to. You really have to think about the point of your life. And when, you know, the physical deterioration, which is inevitable for all of us, overwhelms your reason for living. And we try to avoid thinking that way.

27:19I happen to be one of those people who say, that's the most important question in your life. You better focus on it. And that was the point of the essay. Yeah, thank you for that. That certainly makes sense to me and is a really provocative way to bring it up. And so for our listeners who tend to skew a little younger, but maybe feel behind or overwhelmed or convinced it's too late to build healthier habits in their lives. What does the evidence actually say about starting later in life or starting now? And what small changes still meaningfully will improve your health and your mood and your quality of life?

27:59First of all, it's never too late. And the data are pretty good on that. You know, if you start, for example, exercising at 55. Yeah, very, very important to make these changes early, but middle age is not too late. Even 65 is not too late to do these things. But remember, one of the reasons to start earlier today is that you will have longer. My wife likes to tell me, if you don't do it today, you're not going to be doing it at 85. If you don't do your yoga today, you're not going to stay flexible at 85. If you don't ride the bicycle, do your 30 miles on Saturday, you are not going to be doing that at 85.

28:45And if you want to be doing that at 85, okay, I got to do it today. It's not the gotta. I enjoy it, right? I ride with my wife. We have time together. We ride through nature and we're getting physically fit and the endorphins are happening. It's a lovely, lovely experience. We've touched on this a little bit, But if you're now speaking directly to the person listening who's super busy and tired and just trying to do their best, what single principle of healthy living would you want them to focus on tomorrow or in the next few years? And then how might their life feel different if they did that?

29:23So you have to make wellness a habit. And again, the place I would start is your social relations because it's virtually costless. The great thing about social relationships, it's good for you today, and it's good in the long term. And third, it's also good for the person you're talking to. You're being generous and virtuous by helping someone else as well. And that should make you feel good. So I would start with social relationships. You know, if you haven't called a sibling or you haven't called a dear friend, pick up the phone and talk to them, right? You're going to buy a coffee? Talk to your barista.

29:58Ask him or her, you know, how was your weekend? Or that's a beautiful heart you made on my coffee. How long did it take you to learn that? You know, simple things like that. I would like, frankly, I would like to learn. And it looks complicated. I'm not a very artistic person. So do that. And then I would do a few things in the eating category. And again, don't try to do it all at once. Don't boil the ocean. Again, the data suggests doing one at a time is way better. And get it to be a habit. So if you want to think about exercise, think about, all right, what are you going to do for 20 minutes three to four times a week?

30:36Go out for a walk after dinner or walk a few stairs at work before lunch or just after lunch. Eating. I like to say to people, all right, you got 21 meals a week. Make one new meal every week. one out of 21, focus on making it healthy and doing something new that will make a difference to you. And by the end of a year, you'll have 50 meals that you can make. You can have an easy, have a dinner party, and then you've got a wellness trifecta. You've got great food, right? You're learning something and you're socializing. What could be better? I love it. Dr. Zeke Emanuel, thank you for the rigor, the honesty, the reminder that a good life is a daily practice.

31:25Yes. Thank you, Shoshana. Thank you. My conversation with Dr. Emanuel asks us to rethink what it really means to age well. Not just how long we live, but how we live, what we value, how intentionally we use the time we have. He reminds us that health is not about chasing immortality or optimizing every metric, but about function, meaning, and connection with others. But that raises an important question. If aging is not just about the number of years we've lived, how do we actually measure what's happening inside our bodies over time? What does aging look like at the cellular level long before we feel it?

32:08And how might that knowledge change how we care for ourselves and each other? In today's TED-Ed lesson, scientist Yulia Yolhava walks us through the hidden clocks inside the human body. From telomeres to epigenetic changes to chronic inflammation, she explains how scientists are learning how to measure biological age. And it's more nuanced than just counting the number of birthdays we've had. This lesson is a fascinating look at what aging really means under the surface, and why understanding the biology of aging may help us live longer and better too. With no fees or minimums on checking accounts, it's no wonder the Capital One bank guy is so passionate about banking with Capital One.

32:54If he were here, he wouldn't just tell you about no fees or minimums. He'd also talk about how most Capital One cafes are open seven days a week to assist with your banking needs. Yep, even on weekends, it's pretty much all he talks about, in a good way. What's in your wallet? Terms apply. See CapitalOne.com slash bank. Capital One N-A member FDIC. Hey, it's Adam Grant from Ted's podcast, Rethinking with Adam Grant. This episode is sponsored by the Amazon Kindle Scribe. Up until now, people have had to choose between the focus that comes from writing on paper and the efficiency of laptops and tablets, which might come at the cost of distracting pop-ups and notifications.

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34:11I love how the Kindle Scribe brings my notes to life while making them impossible to lose. I know what I'm working on moving forward. What are you working on? Kindle Scribe. Hi there, it's Adam Grant from Ted's Rethinking Podcast, and this episode is brought to you by ServiceNow. I get to spend my days studying how people think and what it actually takes to change our minds. it's work I find deeply meaningful. But even in meaningful work, there's still busy work. The admin, the repetitive processes, the invisible load that pulls attention away from what really matters. That's where ServiceNow's AI specialists come in.

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35:02And now, your TED-Ed lesson of the day. If you want to learn a fish's age, simply take one of its scales and count the number of bands radiating from its center. For trees, you can count their rings. For narwhals, their tusk layers. And for blue whales, their layers of earwax. When it comes to humans, scientists have yet to find any visible traits that mark our age with anywhere near the same specificity. But in the past few decades, they've discovered small, invisible markers hidden within the body that do change over time. And they may hold even more information about our health, history and future.

35:40The first of these markers was discovered in the 1990s. Telomeres are repetitive sequences at the ends of DNA strands that protect chromosomes from fusing together. However, each time a cell divides, part of the telomere is cut off. These small losses can add up over time, and once telomeres get too short, cells lose their ability to replicate and eventually die. This gradual shrinking process led scientists to identify telomere length as a promising, albeit imperfect, marker of aging. As technology has advanced, scientists learned how to detect even more discrete changes to DNA, like the addition of individual molecular tags called methyl groups.

36:25This DNA methylation can control gene expression, including switching genes on and off. It can occur rapidly and frequently, allowing cells to respond to different situations and perform normal functions. Yet researchers notice that at certain sites in the genome, methylation levels tend to change more gradually and predictably as we age. The reason for this is still unknown, but these changes may be associated with stress or caused by random errors during DNA replication. By measuring DNA methylation patterns from hundreds or thousands of these sites, scientists have developed what they call epigenetic clocks as another way to measure aging.

37:06A third way our bodies change over time is through inflammation. Proteins that are important components of the immune system generally increase when we get sick, then decrease again once our body has recovered. But as we get older, their baseline levels rise, resulting in chronic, low-level inflammation. This process is called inflammaging. Scientists are still unsure why it occurs, but it could be due to repeated encounters with pathogens and other stresses. Another explanation could be the process of cellular senescence. When cells get old and stop dividing, they secrete inflammatory proteins.

37:43And by measuring the level of these proteins, scientists have developed yet another clock that can accurately measure aging. While all three of these markers are great additions to the age estimation toolbox, they don't perfectly correlate with chronological age. Instead, they're best at estimating something called biological age. Biological age is a measure of how well your body is functioning, how much damage your cells and organs have accumulated, and your overall risk for certain health problems. Unlike chronological clocks, biological clocks tick at different rates for different people due to genetic differences as well as health, stress and many other environmental factors.

38:24And different tissues and organs within the body may even biologically age at different speeds. In many ways, these clocks are still a work in progress. For example, most experts recommend against personalised biological age testing. While these tests are commercially available, the value and accuracy of these measurements remain unclear. Currently, these tools work best at the population level, when data from many individuals are analysed. However, many scientists hope to change this in the future, as accurately tracking this information could revolutionise personalised healthcare. For example, one day, a person's accelerated biological age might help doctors detect an unknown health condition much earlier.

39:09And other researchers are searching for ways to slow down or even turn back these biological clocks. Though so far, most attempts at this have been largely unsuccessful. Besides, researchers still don't know if telomeres, inflammation or epigenetics are actually to blame for aging, or if they are simply neutral markers of other processes happening in the body. We may be learning to read the language of aging, but we still have a way to go in understanding its grammar. That was a TEDx lesson by Yulia Yulhava.

39:46And that's it for today's episode. Thank you so much for listening. TEDx Health is a podcast from TED. And I'd love to hear your thoughts about this episode. Send me a message on Instagram at ShoshanaMD. This episode was produced by me, Shoshana Ungerleiter, and Jess Shane. Edited by Alejandra Salazar and fact-checked by Vanessa Garcia-Woodworth. Special thanks to Maria Lages, Farrah Degrange, Daniela Balarezo, Constanza Gallardo, Tansika Sangmarniwang, and Roxanne Highlash. Thank you.

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