Losing weight is hard. That’s probably why almost three-fourths of American adults are overweight or obese. On this episode, we speak with a distinguished doctor and former FDA commissioner who has personal experience struggling with the scale. In this discussion of popular weight-loss drugs like Wegovy, we tackle the biology of weight. We also interview an evolutionary anthropologist about some human populations that don’t have problems with obesity. Is their active hunter-gatherer lifestyle burning more calories?
At The People’s Pharmacy, we strive to bring you up to date, rigorously researched insights and conversations about health, medicine, wellness and health policies and health systems. While these conversations intend to offer insight and perspective, the content is provided solely for informational and educational purposes. Please consult your healthcare provider before making any changes to your medical care or treatment.
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Has the Food Industry Hijacked the Biology of Weight?
While Dr. David Kessler (our first guest on this episode) was FDA Commissioner, from 1990 to 1996, the agency made some major strides towards helping people understand what they are eating. That is when Nutrition Facts labels were standardized and required on all packaged food. In the US, if you buy food that is in a package, that Nutrition Facts label will tell you how big the serving is, how many calories per serving, and also data like the amounts of protein, carbohydrates, fat, and certain vitamins and minerals are supplied by each serving. If information were all that we needed to choose exactly what and how much to eat, there would be no weight problems. Yet Dr. Kessler’s own difficulties with the 10 pm cravings will not sound strange to many of us. The biology of weight may appear straightforward, but the allure of fat, salt and sugar to our reward centers may bypass rational decision-making.
One of Dr. Kessler’s great achievements as FDA Commissioner was holding the tobacco industry to account. How has the food industry escaped similar scrutiny? It seems that the ultraprocessed foods that seem convenient and affordable are contributing to the toxic fat making us sick.
GLP-1 Drugs to the Rescue:
Given the difficulties people have trying to lose weight, it is no surprise that the GLP-1 receptor agonists like semaglutide (Wegovy and Ozempic) or tirzepatide (Zepbound and Mounjaro) have become popular. They seem to reduce the urge to eat and calm the food noise in people’s heads. Those 10 pm cravings Dr. Kessler describes disappear under the influence of these weight loss drug. He has taken such a medication himself to drop the 40 pounds he gained during the intense work period of the COVID-19 pandemic. These medications will be very helpful for many people, but they do have some serious side effects. (You can learn more here.) Healthcare should utilize them as a powerful tool, but just one in a toolbox that should have several.
How Does Exercise Affect the Biology of Weight?
The famous mantra, calories in calories out, suggests that we might be able to exercise our way to a healthy weight. After all, if you burn more calories than you take in, you should lose weight. But anthropologist Herman Pontzer, PhD, has studied people’s energy expenditures around the world. He and his colleagues used a sophisticated technique called double-labeled water to track the energy people burn.
According to their data, humans’ daily energy needs don’t vary as much as we’d think, even when physical activity is vastly different. The Hadza, who get their dinner by tracking, hunting with bow and arrow and running after the injured animal, somehow use roughly the same amount of energy as Americans shopping at the grocery store. Their physical activity is enormously higher, though. (Check out this publication at the Proceedings of the National Academy of Sciences.) Apparently, we need to pay more attention to the calories (actually kilocalories) we consume if we want to understand the biology of weight.
This Week’s Guests:
David A. Kessler, MD, served as chief science officer of the White House COVID-19 Response Team under President Joe Biden and previously served as commissioner of the US Food and Drug Administration under Presidents George H.W. Bush and Bill Clinton. Dr. Kessler is a pediatrician and has been the dean of the medical schools at Yale and the University of California, San Francisco. He is the author of the New York Times bestsellers The End of Overeating and Capture and two other books: Fast Carbs, Slow Carbs and A Question of Intent. Dr. Kessler’s latest book is DIET, DRUGS, AND DOPAMINE: The New Science of Achieving a Healthy Weight.
David A. Kessler, MD. Photo copyright Joy Asico Smith
Herman Pontzer, PhD, is Professor of Evolutionary Anthropology and Global Health at the Duke Global Health Institute. Dr. Pontzer is the author of Burn: New Research Blows the Lid Off How We Really Burn Calories, Stay Healthy, and Lose Weight. His latest book is Adaptable: How Your Unique Body Really Works and Why Our Biology Unites Us.
Herman Pontzer, PhD, Duke Global Health Institute
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Transcript of Show 1449:
A transcript of this show was created using automated speech-to-text software (AI-powered transcription), then carefully reviewed and edited for clarity. While we’ve done our best to ensure both readability and accuracy, please keep in mind that some mistakes may remain. If you have any questions regarding the content of this show, we encourage you to review the original audio recording. This transcript is copyrighted material, all rights reserved. No part of this transcript may be reproduced, distributed, or transmitted in any form without prior written permission.
And I’m Terry Graedon. Welcome to this podcast of The People’s Pharmacy.
You can find previous podcasts and more information on a range of health topics at peoplespharmacy.com. Have you ever worried about your weight? Have you considered the new GLP-1 drugs? Do they help control cravings? This is The People’s Pharmacy with Terry and Joe Graedon.
Today we talk with a former FDA commissioner. Like many of us, Dr. David Kessler has had trouble controlling his weight over the years. He’s utilized the new drugs to overcome his nighttime food cravings.
Dr. Kessler’s new book is Diet, Drugs, and Dopamine, the New Science of Achieving a Healthy Weight.
You’ll also hear from anthropologist Dr. Herman Pontzer. His research shows that people around the world have very similar energy needs.
Coming up on The People’s Pharmacy, the biology of weight. Insights from the GLP-1 drugs and hunter-gatherers.
In The People’s Pharmacy Health Headlines: If the U.S. follows the epidemiological patterns from Japan and Great Britain, we should expect flu season to go into overdrive soon.
Japan is experiencing an early and unexpectedly severe start to its flu season. By early October, more than 4,000 people had been hospitalized with influenza, and many schools and daycare centers were closed to slow the spread of the virus among children.
Some health experts worried that the virus is mutating to become more of a threat. The early arrival of influenza in Japan should not have come as a big surprise. That’s because Australia also experienced an early and severe flu season. It peaked between June and July much earlier than usual. RSV, or respiratory syncytial virus, and SARS-CoV-2 were also rampant at the same time, putting the health care system under stress. British authorities report that the viruses that cause colds are also prevalent in the UK. Flu is on the rise there. As infections rise in Europe and Asia, America may not be far behind.
Viruses are not the only pathogens worrying public health authorities. The World Health Organization released a report this week alerting doctors that common bacterial infections are increasingly resistant to antibiotics.
One in six bacterial infections in the study were no longer susceptible to the usual medications. More than 40% of antibiotics have lost potency over the last seven years. Infections that are harder to treat include gonorrhea, urinary tract infections, and some GI infections such as E. coli. If we don’t develop new ways of treating these pathogens, millions are likely to die in the coming years.
Measles is spreading around the country. Cases reached a three-decade high this week. The very large outbreak in Texas has been declared over. However, there are pockets of infection in Minnesota, South Carolina, Utah, and Arizona. In several communities, students are being quarantined to prevent the spread of infection.
In South Carolina, for example, 150 school kids have been quarantined because children in Spartanburg and Greenville counties were exposed to kids with measles. There have been nearly 1,600 cases reported in the U.S. this year. That’s the highest number in three decades. This virus is highly contagious, and vaccination is the only way to prevent its spread. The MMR vaccine against measles, mumps, and rubella is 97% effective against measles.
New guidelines for COVID vaccinations have a lot of people confused, including pharmacists who administer the shots. At first, the FDA only approved the new immunizations for people at very high risk, or those over 65.
Then, the CDC suggested that anyone who wanted a COVID vaccine would need to consult a healthcare professional first to learn about risks and benefits. Some pharmacists interpreted that guidance as meaning that people would need a prescription before a shot could be administered.
Then there was confusion as to whether insurance companies would pay for COVID vaccines. To make matters worse, different states may be adopting different guidelines. At the moment, though, most insurance companies are paying for COVID jabs.
Life expectancy has returned to pre-COVID levels. That’s because COVID deaths have fallen from the number one cause of mortality in 2021 to number 20 in 2023. Worldwide, life expectancy is now 76.3 years for women and 71.5 years for men. In 1951, female global life expectancy at birth was 51.2 years, and male life expectancy was 47.9 years.
So we have made progress over the last 70 years, but there is an alarming trend. Death rates are climbing among young adults and adolescents. This increase appears to be linked to depression, anxiety, suicide, alcohol, and drug abuse.
A new study in JAMA suggests that preteens who spend more time engaged with social media have a harder time learning in school. Those who increase their time on social media had more difficulty with reading, memory, and vocabulary as assessed by standardized tests. And that’s the health news from the People’s Pharmacy this week.
Welcome to the People’s Pharmacy. I’m Terry Graedon.
And I’m Joe Graedon. For the last several decades, Americans have been getting heavier. Nearly three-fourths of adults have been categorized as overweight, with 40% of us in the obese range. Why do we have so much trouble managing our weight?
We’ll be talking today about the biology of weight. The enormous popularity of GLP-1 drugs like Wegovy or Ozempic can shed some light on this question. We’ll also hear from an anthropologist whose research shows that our couch potato ways may be bad for our health, but they’re not solely responsible for our weight problems.
First, though, we’re talking with Dr. David Kessler. He served as chief science officer of the White House COVID-19 response team under President Joe Biden and previously served as commissioner of the Food and Drug Administration under Presidents George H.W. Bush and Bill Clinton.
Dr. Kessler is the author of “The End of Overeating” and “Fast Carbs, Slow Carbs.” His latest book is “Diet, Drugs, and Dopamine: The New Science of Achieving a Healthy Weight.”
Welcome to The People’s Pharmacy, Dr. David Kessler.
Dr. Kessler, it is such an honor to be speaking with you, but I would like to take issue with the very first sentence of your new book. You state, and I quote, “I am average.” And I would argue that you are far, far from average.
You are a pediatrician. You’re also an attorney. And you have been commissioner of the Food and Drug Administration under President George H.W. Bush. And you’ve been chief science officer of the White House COVID-19 response team.
And that’s just for starters. You’ve also been dean of medical schools. So far from average. But I suspect that in that first sentence, you’re talking about body weight. So what do you mean when you say you are average?
I’ve struggled with my weight my entire life. I have suits in every size. I’ve gained and lost my weight at the end of, you know, had the privilege of, as you mentioned, co-leading Operation Warp Speed.
COVID was an intense period of time. You know, I was working seven days a week, 18 hours a day. I turned around and I found myself 40 pounds heavier. And I had, you know, I had gained weight. I had lost weight. But this mystery of weight, why was it so hard? You know, no one could say, I think, you know, I was able, you know, to do these other jobs.
I mean, no one ever accused me of not having, you know, adequate discipline. But when it came to weight, there I was, I think like many other people, this struggle, this mystery.
Dr. Kessler, you suggest that the food industry has hijacked our health. Would you expound on that a little bit, please?
Well, certainly, you know, let’s just start with what I think you mentioned, which is the real key for me. You know, it’s about our health. This is not about our weight.
The fact is the American body is ill. Only 12% of Americans are healthy. Only 12% when you look at measures of blood pressure, blood lipids, waist circumference, glucose, just basic metabolic measurements.
And the culprit there, I mean, again, this is not about weight. right? I mean, it’s about toxic fat.
That fat that accumulates around our abdomen, that invades our liver, our pancreas, our heart, our skeletal muscle, that toxic fat is causing many cardiac, renal, metabolic diseases that lead to chronic disease. I knew that weight wasn’t good for us. Even as a doc,
I knew it wasn’t good for us, but I didn’t know it was causing these chronic diseases. So the problem is this toxic fat. And then the question is, what causes that toxic fat? And that gets in to, you go back upstream to that, that’s our diet, that’s the food supply, that’s the food industry.
Well, you know, Dr. Kessler, you’ve given us a statistic that is mind-boggling because you’re saying that most of us are not healthy, the overwhelming majority of us. I mean, we have, as you pointed out, hypertension.
Half of the population, adult population has high blood pressure, but we also have blood sugar problems. We also have all kinds of other metabolic issues going on. Is that true in some of the places that you’ve visited around the world? Are other countries also suffering the way we are?
I think, I mean, it’s fair. We’ve always led the world when it comes to public health in good ways. And I think we’ve also leading the world when it comes to, you know, this issue. I think many, many countries are maybe not quite at the extent of the morbidity and mortality that we have, but I think, unfortunately, they’re catching up.
Understand, in our lifetime, right, in our lifetime, 25% of us are going to go on to develop heart failure. You know, some 30 to 40% of us are going to go on to develop diabetes. 25%, you know, are going to have a stroke. And, you know, much of that, all those major killers, that chronic disease, right, those things that cause in our senior years, you know, yes, we may live as long, but we’re going to be in a more disabled state because of that. We’re not going to be as productive.
You know, that is all, I mean, we are coming to realize, I think medicine is waking up to the fact. I mean, cardiologists, endocrinologists, obesity medicine, doctors, you know, I mean, some neurologists, even oncologists. Many of these diseases, cardiac, kidney, endocrinological, metabolic, about 13 forms of cancer, some of the neurodegenerative diseases, they have a common core. And it’s this metabolic adiposity, this metabolic toxic fat that is causing it.
And for the first time, I mean, the good news is for the first time, we have the tools that can fix that. No magic answers, right? No magic pills, right? But we do have tools that we can reclaim our health if you want to.
Well, we do want to talk about that in just a moment, but I asked you about the food industry, and we actually have a government agency that is supposed to be looking out over oversight, supposed to be doing oversight on the food industry. It’s an agency you’re very familiar with. We call it the Food and Drug Agents Administration.
So what did the FDA get wrong about public health and nutrition?
So back in the 90s, when we had the opportunity to be at the agency, you’ll remember we did, you may remember that we did the nutrition facts panel, right? I mean, go pick up any, I don’t know if there’s any packaged food in the studio, but that nutrition facts panel, that few inches has calories, fat, sugar, protein. And it was hailed as a major advance, right? And it was for its day, right?
And still many people rely on that when they look at food that they buy. What they did not, what we didn’t get, and I don’t think anyone really got, were the consequences, the biological effects of that fat, sugar, and salt in our bodies. What was it doing to our insulin levels? What was it doing to the way we deposited fat? We didn’t understand the consequences fully of what we were putting in our bodies.
Dr. Kessler, you are renowned for going after the tobacco industry and the impact of nicotine. Tell us how the food industry evolved its own, shall we say, addictive power when it came to food. And we just have a couple of minutes before the break.
So in order to feed a hungry nation back in 1930s, 1940s, food industry learned to process food, to create this sort of alternative food system, this industrial food. It was able to extend shelf life. It extracted certain very cheap chemicals from food ingredients, took those, took out the water, were able to ship things over long distance, added in palatability, added fat, sugar, and salt.
These other modified starches and other chemical ingredients, right. And this was the modern industrial processed ultra food supply. And the advantage, it was cheap, it fed a hungry nation, it was convenient, and it replaced traditional foods. We took fat, sugar, and salt, put it on every corner, made it available 24-7, made it socially acceptable to eat anytime while living in a food circus.
And the consequences? Consequences is this toxic fat.
And what makes that fat so toxic?
It gets into your organs. It gets into your pancreas. It gets into your liver. That liver releases these inflammatory substances and hormones and free fatty acids. And fat goes in places where it’s not supposed to be. It’s not supposed to be in your heart.
It’s supposed to be a little in your liver, but it gets into your muscles and your pancreas. And it causes major significant cardiac endocrinological renal disease.
You’re listening to Dr. David Kessler. He’s a former commissioner of the Food and Drug Administration under President George H.W. Bush. Dr. Kessler has also been dean of the medical schools at Yale University and the University of California, San Francisco. His most recent book is “Diet, Drugs, and Dopamine: The New Science of Achieving a Healthy Weight.”
After the break, we’ll find out what Dr. Kessler means by the 10 p.m. cravings and why they’re so dangerous.
How do GLP-1 drugs help people achieve their desired weight?
How can we make choices today that will help us achieve a healthy weight in the future?
You’re listening to The People’s Pharmacy with Joe and Terry Graedon.
Welcome back to The People’s Pharmacy. I’m Joe Graedon.
And I’m Terry Graedon. Today, we’re talking about the biology of weight. Why are so many of us having trouble achieving and maintaining a healthy weight?
Americans have fallen in love with GLP-1 receptor agonist medications. You’ve probably heard of drugs like Ozempic, Wegovy, Mounjaro, and Zepbound. They’ve captured the imagination of millions of people. How do they help people lose weight?
We’re talking with Dr. David Kessler, who served as chief science officer for the White House COVID-19 response team under President Joe Biden. He’s a former commissioner of the Food and Drug Administration under President George H.W. Bush, and he’s also been dean of the medical schools at Yale University and at the University of California, San Francisco.
His most recent book is “Diet, Drugs, and Dopamine: The New Science of Achieving a Healthy Weight.”
Dr. Kessler, we’re going to talk in a moment about this revolution called GLP-1 drugs. But first, you are very personal in your book, and you talk a little bit about this idea of 10 p.m. cravings that was your enemy. Tell us what happened at 10 p.m. for you.
For me, 10 o’clock at night, if I’m working 18, 19-hour days, certainly during COVID, or even going back to when I was in school, I think many of us can remember medical school. I had to study for the next exam or do that paper, and at 10 o’clock, I’m tired, I’m fatigued. I need to make it through the next three or four hours.
And I go, yeah, should I go down to the refrigerator? Should I have something? Maybe it’s not so good for me. This struggle, right? So, I mean, there are these, understand that these are, I’m not, 10 o’clock at night, I had just eaten dinner. I mean, I wasn’t doing this for fuel. I was doing this to change how I feel.
I mean, and I think that’s what is so important to understand that food, I mean, in essence, I mean, changes how we feel. I mean, it works on the reward centers of the brain. I mean, it’s psychoactive. Those reward centers of the brain, you know, are really, they are the addictive centers of the brain.
We think about addiction as for the weak or the downtrodden, but the human brain evolved to deal with scarcity, not abundance. And for much of human history, there was no guarantee when our next meal would come, when it would arrive. So our biological systems are designed to seek out that sweetness, that most energy-dense food. And we’re wired to focus on the most salient stimuli.
And the way this works, I mean, when you think about, when you understand addiction, we have just, I mean, addiction is part of all of us, those circuits. It’s this cue-induced wanting. So 10 o’clock became the cue, right? That fatigue became the cue. So that 10 o’clock at night, I’m not eating for fuel. I’m eating to change how I feel.
So Dr. Kessler, how do these GLP-1 drugs help people achieve their desired weight?
They are highly effective. But bottom line is they work. there’s no real magic, right, to them. I mean, they work by keeping food in our stomach longer.
You know, there is this spectrum, right? I mean, we’ve all, this sort of satiety spectrum. And I think we’ve all experienced this. You get the flu, your GI tract doesn’t work as well, food’s staying in there. When food stays in my stomach longer, I don’t want to put anything else in. I mean, look, the thing, whether it’s diet or drugs or surgery, get you to lose weight, they all do it by decreasing appetizing, getting us to eat, put less in our mouths to eat less.
Look, that mantra, that fail, eat less, exercise more. Absolute failure, right? Didn’t work. It didn’t work because of the addictive circuits. But what these drugs do is they help you to eat less. How do they do that? Right?
I mean, it’s these addictive reward circuits that are at play, this wanting this 10 o’clock at night. But those feelings, right? I mean, these feelings, the GI brain access, I mean, there’s another set of circuits beyond the addictive circuits. They’re called the aversive circuits. I mean, so this food staying into my stomach longer, that’s in part controlled by the hindbrain, not the reward circuits, the area postrema, the nucleus solitarius, those circuits counterbalance.
So those feelings counterbalance, those aversive feelings counterbalance to reward circuits. I don’t want to put anything else in my stomach. I learn to eat smaller. Maybe I do that unconsciously. But you have this balancing, these aversive circuits, these reward circuits, and they dictate how I feel at the moment and whether I want to eat or not.
Dr. Kessler, a lot of people now, because, well, Novo Nordisk, the manufacturer of Ozempic and Wegovy, has made billions and billions of dollars. There are a lot of people who say, well, this is simple, all I have to do is take the shot. Or in the case of some of these drugs, now they’re taking the pill. I don’t have to think about food choices, I don’t have to think about exercise. All I need is a GLP-1 agonist.
So it seems like this is just part of the equation. It may be the dopamine part. You feel that satiety. You don’t feel like I need to snack at 10 p.m. But what about the food choices and the exercise?
So how long are you going to stay on that pill for? That drug is going to work while you’re on it. Now, look, it has, let’s just agree, these drugs have real adverse events, right? I mean, this is no walk in the park.
This notion that these are not be-all and end-all, right? The fact is that if you look, the average person is on these drugs today for about eight, nine months, right? These drugs work while you’re on them. They don’t work. You don’t expect them to work when you go off them. But what’s going to happen? People are going to spend thousands of dollars, go on these drugs, lose this weight, stay on this for eight to nine months. When you lose weight, you lose muscle also.
You go off these drugs and then people are going to gain back that weight and say, we’re going to turn around in three, five years and go, hey, this is one big, massive failure. So what are you going to do? There is no end game when it comes to weight. It’s a chronic, relapsing condition. Once you’ve gained that, yes, let’s protect that next generation from this. But if I’m going to go off these drugs, or if I don’t want to be at a dose, we’ve got to get the information how these drugs can be used in the real world. But what are you going to do when you go off these drugs?
And that’s why what these drugs, the greatness about these drugs is they allow you to recondition your relationship with food. So while you’re on these drugs, you can learn to eat. And what you hope is that if you want to go off them, maybe you want to stay on them, but if you want to go off them, you’ve changed that relationship with food, right? So that you then off these drugs can maintain the weight because losing the weight is not the hard part. It’s maintaining that weight.
So, Dr. Kessler, how do we reshape our relationship with food during the nine or ten months that we are using Ozempic or Wegovy, for example?
That’s one of the great questions we’re learning a lot. Watch people on these drugs. Ask them how their food preferences change. I mean, if you don’t want to put, you know, imagine this now. You feel like there’s a lot more in your stomach, you’re satiated much quicker. So you don’t want to put certain foods in your stomach.
But the taste preferences, you know, for me, I mean, it was the first time I was eating vegetables, right? I just did for some reason, and I’m not sure I fully understand the biology, these taste preferences change for some people. Look, I am humbled because the one thing we have to recognize is there’s great variability, great variability in responses, how much people wait, what their adverse events are, what do they feel? I mean, does it make them, does it push them to the edge of nausea? Do they feel anything? Do they not feel anything?
We all, I mean, are different, but there is, there’s something about when you’re, when you’re, for me, I was just eating much smaller portions. And I learned to want to do that. I didn’t like eating large portions while I’m on this because I wouldn’t feel good. And I try to carry that over. But understand that can fade. You go off these drugs, you condition yourself, you have that new learning. But over time in this environment of fat, sugar, and salt on every corner, those addictive circuits are going to pop back up and maybe I have to go back on these drugs.
But again, my old agency has to do a better job working with the companies to get data on how can we use these drugs in the real world. Can I use these intermittently? Will they work intermittently?
Dr. Kessler, I would love to spend the next 10 minutes or so just talking about how people can use these marvelous new tools to actually get healthier. So let me ask you, how can we optimize nutritional quality while we’re cutting calories?
Once you start, once you’ve gained weight, right, and have the weight to lose, right, your body’s going to work against you. Those reward circuits, those metabolic circuits, right, are there, right? And you have to understand you’re trying to get the body to do something it doesn’t want to do, right? I mean, and so those addictive circuits are at play, right? And I mean, if those addictive circuits want it, I have to, I really have to, in the end, change my relationship with food. I got to change what we want.
What was the, I mean, if you look at the great public health success, right? I mean, certainly of our lifetime was cigarettes. The great public health failure? Obesity. What did we do in cigarettes?
I mean, at the turn of the previous century, the fact is that the cigarette industry took these products and made it seem sexy and glamorous and adventuresome. There was a march down Fifth Avenue for emancipation, women’s rights, voting rights. Right? Um, that they so these were positively valence what did we do in tobacco what we we changed the valence of that product we had this critical perceptual shift we began as a country to look at these products not as something that was sexy glamorous something that I wanted something that was going to make me feel better but for what they were they were deadly disgusting addictive you know products and you know if something’s sexy and and it’s positively valence I’m going to approach it.
If it’s negatively valanced, I’m going to avoid it. Food is much harder. The problem is not food. The problem is this ultra processed food, this industrial food, these large portions. I got to change what I want. I got to change how I perceive it.
Once you understand that food is going to result in that heart failure, is going to result in that diabetes, is going to result that I can’t pick up my grandkids. It’s going to result in years of disability later on in life. I mean, that’s the goal. We have to change what we want.
Of course, humans are not that great at imagining what we’re going to want in the future and making that overcome what we’re doing right now. The potato chips right now might sing a little louder than the idea of picking up your grandchild in 10 or 15 years.
Well, you know, you’ve just, that whole field of behavioral economics, delayed discounting, you’ve just summarized and just perfectly in 10 seconds.
Look, the fact is, I mean, we didn’t get this as docs. Medicine didn’t get this. Again, we always thought weight just wasn’t good for us. We didn’t understand this toxic fat is causal.
Once we wake up to that fact, once we see, and I think this is starting to occur. I think that people really understand the diet and what we’re eating. This ultra-formulated food is at the core of this. Again, these drugs can be one tool to get us to eat less, exercise more. They help with it. They calm down those addictive circuits. But we really have to change.
Look, if someone came down from Mars and looked at what we were doing, We have one industry making billions of dollars that make us sick. And we have another industry making equal profits, trying to treat what that former industry does. Something’s wrong with that picture.
We got to get to the root cause. But I can’t wait for the food industry or for people to change my food environment. We got to be able, the real choice, you talk about willpower, is do you want to make a decision? Do you want to reclaim your health? Because if you do, then get help, right?
I mean, these addictive circuits, you can’t expect to do these yourself. Get a good dietician. Get somebody who is skilled in taking care of this toxic fat, I mean, who understands about obesity and weight.
And Dr. Kessler, I know that our listeners want to know, how are you doing? You gained weight, understandably, during the COVID crisis when you were working 18 hours a day and trying to make a difference in the public health of the American population and the world. So now that you’ve actually tried the GLP-1 agonist-type drugs, what does the new Dr. David Kessler look like in the mirror?
I’m good for now. I’m good today, you know, dramatically reduced my percent body fat, but it’s a journey. I can’t tell you about tomorrow. But I think, you know, my percent body fat right now, again, as I said, it’s about half. Metabolically, much better. I mean, that 40 pounds is gone, and an additional 20 pounds is off.
Is it easier? Sure, but it’s no picnic. For me, I mean, I was sick, my body was sick. You looked at all metabolic, I was pre-diabetic. I didn’t want to be there.
But that’s a choice. I mean, the most important thing is can we prevent, can we give our children the gift of not having gained the weight in the first place, gaining this toxic fat in the first place, so they don’t have to struggle with it? That’s our job.
Dr. David Kessler, thank you very much for talking with us on The People’s Pharmacy today.
You’ve been listening to Dr. David Kessler, who served as chief science officer for the White House COVID-19 response team under President Joe Biden. He’s a former commissioner of the Food and Drug Administration under President George H.W. Bush, and he has also been dean of the medical schools at Yale University and at the University of California, San Francisco.
He has written several books, including “The End of Overeating,” “Fast Carbs, Slow Carbs,” and his most recent, “Diet, Drugs, and Dopamine: The New Science of Achieving a Healthy Weight.”
After the break, we’ll hear from an anthropologist. His intriguing research suggests that people around the world use roughly the same amount of energy a day.
Some of the people in his study hunt their own meat and gather their own plant foods. Doesn’t that take a lot of energy?
If you were a hunter-gatherer tracking antelope across the savanna, how many more calories would you burn?
His study suggests that the main cause of obesity in America is what we’re eating.
What should we be doing for our health? Are there lessons from anthropology that can help us achieving a healthy weight?
You’re listening to The People’s Pharmacy with Joe and Terry Graedon.
Welcome back to The People’s Pharmacy. I’m Joe Graedon.
We’re considering the biology of weight today. Usually, any discussion of weight has to include the idea that calories in and calories out must balance.
That has led to suggestions that we need to be more active. If only we walked or ran or cycled a lot more instead of riding or sitting, wouldn’t we be able to manage our excess pounds?
To find out, we turn now to Dr. Herman Pontzer. He is professor of evolutionary anthropology and global health at the Duke Global Health Institute. Dr. Pontzer is the author of “Burn: New Research Blows the Lid Off How We Really Burn Calories, Stay Healthy, and Lose Weight.” His latest book is “Adaptable: How Your Unique Body Really Works and Why Our Biology Unites Us.”
Welcome to The People’s Pharmacy, Dr. Herman Pontzer.
It’s great to be with you.
Thank you, Dr. Pontzer. It’s nice to have you here. We just got done talking with Dr. David Kessler. He was former FDA commissioner, and he is author of “Diet, Drugs, and Dopamine, The New Science of Achieving a Healthy Weight.” But we’d like your perspective on this issue. You’ve tackled this controversial topic of weight control by traveling to Hadzaland in Tanzania.
Please, can you explain why you went all that way to understand the balance between energy intake and energy expenditure? You know, I think a lot of us who don’t really understand all this metabolism stuff very well just call it calories in, calories out. Why did you go so far away and what did you do?
Yeah, thanks. So, you know, my training is as an anthropologist. I’m interested in how our bodies evolved, how they got to be the way they are today, and then how that kind of interaction between our evolved bodies and our modern lifestyles plays out for each of us in terms of health and the way our bodies work today.
And I focus, you know, my lab focuses on energy expenditure, calories in, calories out, because that is the currency of life, right? The game of life for any organism is to take energy from its environment and survive and reproduce. That’s the game of life that all organisms play. Now, our species, we evolved as hunter-gatherers, right?
So for over 2 million years, we’ve been hunting and gathering. And that’s the lifestyle in which our bodies evolved. So that’s kind of the ecologically relevant context to understand our bodies. And for a long time, up until we did this work with the Hadza in northern Tanzania, we didn’t understand how our metabolisms looked in a hunting and gathering lifestyle, right?
We had some data from the U.S., Europe, you know, westernized, industrialized places. But we didn’t have any data on the most relevant context for our species, hunting and gathering.
And there really aren’t that many places on Earth where people are still doing hunting and gathering. The opportunity to study it, as well as the opportunity to live that way, has diminished a lot.
That’s right. Most of these populations have been moved to cities or towns. They’ve been developed.
Tell us a little bit about the Hadza.
Yeah. So they’re a hunting and gathering community in northern Tanzania. Now, what does that mean? That means every morning they wake up and men hunt for wild game, or sometimes they go and collect wild honey. The women go out and collect wild plant food. So sometimes that’s picking berries. Sometimes that’s digging for wild tubers. And they do that every day.
They don’t have any cars or electricity or plumbing or anything like that. They live in grass houses in the middle of the open savanna in northern Tanzania. So they’re focused on food. That’s right. Their whole economy, their daily life is focused around getting calories, right? And then, of course, living their lives, burning those calories on all the things they do all day.
And I suspect that getting food takes a lot of calories.
Well, that’s exactly it. So we had this idea when we started this project that being so active as they are, right, they get more physical activity in a day than most Americans get in a week, right? We know that. Men get 19,000 steps a day.
Women get 13,000 steps a day and often with a kid on their back, right? So it’s a really physically active way to make a living. And all hunting and gathering groups, we think that’s pretty typical for them. And then that means it’s pretty typical for us in the pretty recent past.
And so we wanted to ask the question, is that more traditional lifestyle, does it burn a lot more calories every day than our modern lifestyle does? Because we’ve all heard the story. These modern lifestyles that we live in, you know, they’re too comfortable. They’re too easy. We don’t get enough activity, and that’s leading to obesity, perhaps, because we’re not burning enough calories.
Yeah, sitting or lying down or just not doing anything.
That’s exactly right. So we wanted to understand what that gap is. How many more calories do you burn as a hunter-gatherer? And so we use this state-of-the-art technique called doubly labeled water. It’s this isotope tracking technique that allows us to really measure how much carbon dioxide the body makes all day.
You can’t burn calories without making carbon dioxide. You can’t make carbon dioxide without burning calories. So it’s a really accurate physiological way of measuring calories burned. And we do it over about a week or 10 days. And we went there to kind of document how many more calories they’re burning because, again, they’re so physically active.
And the shock was we got home and we analyzed our data. They don’t burn any more calories.
I know it. I couldn’t believe it either. And, you know, we did all the the first thing we assumed was that we’d gotten it wrong. Right.
That would be a logical assumption.
That’s right. So we have other ways of double checking these data. We had a heart rate monitoring project that we did along with this. We had a whole other way of estimating energy expenditures.
Everything lined up to where these are solid data, right? For this hunting and gathering population, something that looked a little bit like the past would have looked like for all of us and what traditional lifestyles look like, you know, the world around. They are burning no more calories every day than folks in the U.S. and Europe and other industrialized countries.
So we’re very profligate with our calories.
Well, that’s right. I mean, what it suggests is our bodies are adjusting to lifestyle in interesting ways, in ways that we kind of hadn’t appreciated before this study. So you and I, and well, I don’t know about your lifestyle, but I know mine. I’m not as physically active as a Hadza man. I don’t get 19,000 steps every day.
Definitely nowhere close.
And so my body is burning energy on physiological tasks that their bodies are not. I’ve re-juggled the way I spend my calories, right? It’s like living on a fixed economy. It’s the same number of calories coming in and out. We’re just spending them on different things.
And so if you’re a Hadza man or woman, you’re spending more of that energy on physical activity. That’s definitely true. We measured some, we did some tests to study like the cost of walking, for example.
There’s no magic going on. They’re still burning those calories walking. But they’re burning more on walking and more on activity and less on other things. And we’re doing the opposite.
We’re spending more energy on things like perhaps things like inflammation, things like stress response, things like having reproductive hormone levels that are quite high. All these things kind of ramp your body’s metabolism up. And we can do that here in this lifestyle, but we’re not doing it if we were in that lifestyle.
Let me see if I’ve got this right. So here are these people who are, in the case of men, nearly 20,000 steps a day, every day, day in and day out. And yet the calorie expenditure is very similar to ours where we may only be walking 5,000 or 6,000 steps a day. We’re sitting in front of our computers.
And if you hit 10,000 steps a day, you pat yourself on the back.
Yeah, it’s like, oh, yeah, I played tennis and then I went for a walk and then, oh, boy, 12,000 steps, I’m great. But let’s cut to the chase: It’s really about the weight. That’s what we’re concerned about. It’s about the obesity epidemic in the United States. Were there very many obese Hadza? Yeah, there’s none, as you can imagine.
Now, they’re not, you know, they’re a healthy weight, right? So there’s not malnutrition or anything like that. There’s a healthy weight population. But yes, obesity, non-existent in this group. You know, people often ask if there are periods when the Hadza are starving, basically, they don’t have any food. And you might think that if you look at the pictures there, you see an empty landscape. And that’s what I see, too.
But they don’t see that. They see a landscape that’s full of food if you know what to look for. Now, so they might not have access to their favorite foods all the time. They like to eat meat. They like to eat particular kinds of plant foods that taste nice. So they don’t always have their preferred foods all the time. But they can always get food.
I’ve never seen a Hadza camp that wasn’t, you know, where the people were unable to get enough to eat every day.
So you haven’t seen malnourished children, et cetera?
No, you really don’t see that. And in fact, we’ve done things like we’ve tested for ketone levels in urine tests, right? Which would be one indicator, physiological indicator of starvation. We’d never see that. We never see ketone bodies in the urine. Now, that’s not the most precise test.
But it’s an indication for sure. If you just look at heights and weights of kids and adults, these are healthy folks.
So the difference, please, open that envelope.
Right. Obesity in the U.S. has to be a question of diet, right? That has to be the main problem. We’re bringing too many calories in. Because if the energy expenditure that we’re all experiencing, no matter what our lifestyle is, is kind of all the same. If you can’t move the needle on energy expenditure, then obesity, which is this balance between energy in and energy out, has to be about your diet and taking too many calories in.
Now, Dr. Pontzer, you and your colleagues have just published a paper in the Proceedings of the National Academy of Sciences, looking at this same question, but with a bigger data set. You didn’t just look at the Hadza, you looked at a bunch of other groups as well. Tell us about it, please.
Yeah, that’s right. So, you know, in the years since that Hadza study, we’ve had the chance to do this with a couple other populations here and there around the world. And we find similar results in sort of isolated other populations. But we didn’t have an opportunity to ask, OK, let’s put our arms around all the populations that we have data for, try to get a really broad idea of energy expenditure versus lifestyle across the whole globe.
And the reason we hadn’t done that before, nobody had done that before, was that this isotope tracking technique we use to measure energy expenditure, it’s expensive and it’s technically a challenging thing to do. There aren’t many labs that do it. And so there had been no huge multi-population study to look at this yet because it just wasn’t feasible.
Since about 2016, my lab and several others across the globe have collaborated, put all of our data together from all the studies that we’ve done over the years. And now finally, we have this huge data set, 10,000 plus individuals total, that we can ask questions with big samples, looking across lifestyle, across age, all these sort of big data kind of questions we can finally ask using this technique.
For this study, we had 34 populations. The Hadza were there, U.S. is there, countries in Europe, Asia, countries that have low economic development, middle, rich countries, farming communities, really the full economic spectrum of human existence. And we could ask the question, OK, with a really broad sample, with a really big data set, can we see an effective lifestyle and especially economic development on energy expenditure and obesity risk?
And the envelope, please?
Right. So just like the Hadza study, we don’t see a big effect of economic development on expenditure. In fact, if you just look at total calories burned per day, people in rich countries burn more. Why is that? Because they’re bigger, right? We tend to be bigger in more developed countries. And your total body size is the biggest predictor of how many calories you burn. If there’s more of you, you’re going to burn more calories. But even after we correct for body size—which we always do in these analyses—we see the same things we saw with the Hadza study. No effect of economic development on energy expenditure, hardly at all.
And so what really matters is?
It is diet, right? The big driver of obesity across these 34 populations has to be the calories that we’re eating. And we were able to do additional analyses asking things like, well, what is it about the diet?
Maybe it’s the amount of meat that people are eating. That doesn’t seem to be a factor. What is it? Maybe it’s the amount of ultra-processed foods. And there we do see an effect that populations that are eating more ultra-processed foods tend to be the populations with the highest levels of obesity in our sample set.
So, you know, the study wasn’t designed to look at that specifically, but it’s a good direction to go next.
So what can we learn from this research? Because, like you say, I mean, no one has ever done anything of this size before across this many cultures. Is there a take-home message about the food? And what should we and what shouldn’t we as a population be doing? Well, let’s start with the exercise portion first, right?
It’s still important to exercise and get physical activity. There’s nothing about the study that says exercise doesn’t matter. On the contrary, we know exercise is still really important. It’s good for us. It’s good as we age. It’s good for mental health. There’s so many good things about exercise. But…
Because human bodies were meant to move.
That’s exactly right. That hunting and gathering past that we all share, when our ancestors were getting 10 or 20,000 steps a day, that is the way that we evolve. That’s what our bodies expect. And so if we don’t do that in our lives today, we set ourselves up for illness.
Okay, but exercise is not going to fix the obesity crisis. And the obesity crisis is not because of a change in physical activity and lifestyle. It’s because of a change in diet. And so when we want to tackle obesity specifically, we need to be focused on diet.
What are we putting in our supermarkets? What are we putting in our school cafeterias? What are we putting in our baskets as we go shopping? What are we putting in our cupboards, right? We have to think about diet and controlling, trying to find a way to eat healthier and limit how many calories we eat so that we don’t over-consume.
Dr. Herman Pontzer, you look fabulous. I mean, you are a thin guy, but you’re not scrawny. You look like you’ve been practicing what you’ve been studying. That is to say, you look like you’ve been careful about what you eat for a long time.
When we spoke with David Kessler, he sort of admitted as how he’s been overweight for most of his life and that it’s been a challenge. And he has been a, I’d say, an advocate for the GLP-1 agonist drugs. You know, you’ve all heard about the Ozempics and the Zepbounds and the Wegovys.
And, you know, these drugs have, quote, unquote, revolutionized weight control. So just on a personal level, how do you maintain your excellent body weight?
Well, I appreciate that. You know, I like to be physically active, I like to run, I like to rock climb. Those are my two big outlets for getting activity in. I like to be outdoors. So that’s never been, you know, it’s never been hard to push myself out the door.
But based on your research, that’s not the primary thing, right?
No, that’s right. So that’s not what’s keeping me thin. What’s keeping me thin is that I also have been lucky to have a pretty good relationship with food. I am not the kind of person who has food cravings all day. I know some people who do, people close to me who do.
And that sounds like a much harder way to sort of manage what you’re eating. I enjoy food. Of course, I enjoy food with friends most of all, but I don’t feel pushed to over-consume. And so I’ve been lucky that way because I know that not everybody has that same wiring.
So you’re not tempted to have seconds, or thirds, or another dessert?
Not particularly. And if I miss lunch, I don’t mind.
So what can we learn from your example, especially when it comes to that really big deal these days about ultra-processed foods?
Yeah, well, you know, I think everybody loves snack foods and junk foods. I mean, come on, they’ve been chemically engineered and focus group tested to be delicious.
You don’t even have to be human to love a snack food. Our dogs like those crunchy things that we get in packages, cod crisps.
They like these things. I think it’s just cods and fruit.
But they crunch, very satisfying for dogs.
And, you know, a lot of crunchy stuff is satisfying for humans, too.
That’s right. So, you know, what I’ve noticed, so, you know, I’m 48 years old. I have certainly noticed the last 10 or 15 years that I appreciate you saying I look good, but I feel a lot different than I did in my 20s. That’s for sure.
And so, you know, I have made an effort to say, well, look, I can’t control what they put in the supermarket, but I can control what I put in my basket. And I’m not going to have a lot of soda and, you know, snack foods that I know I’ll eat the whole thing in my house, right? And, you know, I’m lucky enough to have good supermarkets nearby that I can make those decisions.
But I do that so that my personal environment doesn’t tempt me to over-consume, because there are certainly foods that I would absolutely love to over-consume.
Dr. Pontzer, I would love to get a sense of what it was like to hang out with the Hadza. These people are, as you have described them, real hunter-gatherers. Food is critical to their survival. And so they spend a lot of time going out and searching for food. What are they eating first? And how close to the edge are they?
In other words, do they have times when it’s kind of hard to find food and other times when it’s plentiful? Give us some sense because you kind of went back in time.
Hmm. Well, I’m going to push back a little bit there and just say, I know what you mean by that. But I think some people listening to this would think, oh, well, that means the Hadza are some kind of, you know, stuck in amber kind of, you know, community from the past.
And of course, you know, that’s not true. Every culture today is we’re all equally here. We’re all equally modern.
And with us today. But, you know, you’re absolutely right that a population like the Hadza provide an opportunity to ask, you know, what it was like back then because they share so many elements of a lifestyle that we think was common in the past. And so what’s it like?
Well, you know, if you’ve been able to travel and see other cultures internationally, you’ve probably had this experience. The first thing you notice are all the differences, right? It’s a different language. It’s a different way they’re dressed. It’s a different kind of, you know, all the differences.
And then if you have a chance to stay there for a while, pretty soon you start to notice, oh, wait, that looks, you know, this is like, you know, kids playing kids games is the same no matter where you are on Earth. Husbands and wives arguing about something, that’s the same no matter where you are on Earth. Friends telling stories is the same everywhere.
Even if you don’t understand the language, you understand the laughter, right. So I think that’s what I take away when I go now is they feel like it feels a little bit more like home. And I see our commonalities. I see what’s shared there.
Now, what’s absolutely not shared is that when they wake up in the morning, they have to find their breakfast, right? I mean, maybe they have some stuff left over from the night before, but they don’t just crack open the fridge and have a yogurt, right? That doesn’t happen. And so what kind of foods are they eating?
Well, men are eating wild game. And so in that part of the world, you’re talking about zebra, giraffe, different kinds of antelope, smaller game as well. Men also, when they’re not hunting, they’ll bring home, they’ll kind of chop into this. Every hodge a man leaves the camp with a bone arrow that they make themselves and a hatchet. And so if they’re not hunting with the bone arrow, they’re using the hatchet to chop into trees and get at wild honey. The bees make their hives in trees there. And so honey is a big part of the diet. It’s delicious. Meat is, you know, maybe sort of 40 or 60 percent of the diet, depending on the time of year and that kind of thing.
And then the women are getting plant food. So that could be wild tubers. That could be berries. That’s kind of baobab fruits, that kind of thing.
Now, you said that the men are hunting and they’re eating wild meat. I’m assuming, and I shouldn’t assume. So let me ask you, are they sharing the food with the women?
Thank you so much for that. Yes, everything is shared, right? And that’s a real commonality that we see across hunting and gathering groups. Sharing is what makes it work. I’ve been teaching anthropology and human evolution for a couple decades now. What I always tell my students is the big change that put us on our path to being human and not being like the other apes is hunting and gathering.
And it’s not the hunting or the gathering that’s so important in that equation. It’s the ‘and,’ right? And by having some folks hunt and some folks gather and you share the food at the end of the day, you get the advantages of being, you know, thinking about this sort of ecologically, the advantages of being a plant eater and the advantage of being a carnivore, you get them together.
And that’s why our species and our ancestors have been so successful because that’s, you know, it’s unlike any other species in the way that we make a living.
Tell me about the hunting piece, because I’ve seen the arrows, which are really cool, and the bows and how good they are with the bow and arrow. So you’ve been out on a hunting expedition. Give us a description.
It’s remarkable. So it’s a lot of walking. You walk and walk and walk.
Sometimes. So that’s, yes, sometimes they have dogs. I would say maybe 10 or 20 percent of the time that I’ve been in Hadza camps, there have been dogs. Often it’s just a man that’s just walking. They typically go out alone unless, you know, you’re able to talk your way along with them.
And, you know, they’re very good at what they’re doing. So they’re very quiet. They’re very attentive. They’re seeing things that you’re not seeing on that landscape. And they notice the game before the game notices them. And then they’ll stalk and try to get a shot. They’re so good with their bows and arrows. It’s a fun one.
When my first trip to Hadza camps, of course, it’s a big camping trip for us, basically. We fill a couple Land Rovers with camping gear and science gear for, you know, maybe you’re there for a couple weeks or a couple months. And so one of the essential pieces of camping gear is a tin full of instant coffee.
That’s an absolutely essential piece of research gear there because you can’t get up in the mornings without some instant coffee.
And so we had this empty tin of instant coffee. It’s called Africafe. And I don’t know, we got into our heads one day. Let’s have a—because we were so impressed at watching these guys shoot bow and arrow—let’s do a competition to see, you know, who can hit the can from pretty far away.
And, you know, whoever wins, you know, they can keep the can or whatever, because it’s a nice tin can. It’s a valuable thing to have. And so we set it up while the guys were all out hunting, and we set it up was probably 20 or maybe even 30 yards away. It was a good distance. I grew up, you know, in a rural part of Pennsylvania hunting and shooting bow and arrow a little bit.
And so it looked to me to be a very far distance to hit a pretty small tin. And before the guys even came back from camp, their kids were lining up and having a laugh and hitting that can every time they shot these bows. And I thought, oh my God. And so we had to move it twice as far out to hold the actual competition. And even then the guy, it was like, it was, it was too easy.
So, you know, these, they’re remarkable shots. They’re remarkable trackers. They, you know, if you think about it this way, they’re remarkable ecologists, biologists. They know each of those species so well and they know their habits and it’s, it’s just, it’s feels so special and you feel so lucky to be able to hang out with them.
What was it like to hang out with the Hadza? I found one of your sub-chapters very intriguing. It’s titled, “Urine for a Surprise.” And urine was U-R-I-N-E. How in the world did you get people to give you urine samples?
Yeah. Well, that brings up a larger issue is how do you do community work ever in these, you know, it’s not my community, right? We travel there. And so the answer is you have to build up a relationship. And so I’m lucky to work with a guy, Brian Wood, another anthropologist at UCLA. And he’s been doing work with the Hadza his whole career. And he speaks Hadza.
I should say that when we would go and work with the community, we typically speak Swahili. So you have to learn Swahili to go there. And they grow up speaking both their own Hadza language and Swahili. And so, you know, you have to build these personal relationships and these community relationships.
And then once you’ve got that and you’ve got these sort of friendships and people you know, then they’ll trust you like any community would to, you know, if you want to do these research projects that they can kind of get behind, then that’s how that works. You don’t ever just parachute in. You can’t do that. That’s not how it works.
I think you probably have some sense of that, Joe, based on our initial exposure to field work, which was in Santo Tomas, Mazaltepec in the Oaxaca Valley.
Yes, in Mexico. And they grow up speaking both Spanish and Zapotec because the Zapotec is the mother tongue. But nowadays, I think pretty much everybody speaks Spanish as well. When in the early 1970s, when Joe and I stayed there, there were a lot of the older women who didn’t speak Spanish, which was a little inconvenient for me because I hadn’t yet learned Zapotec. The only thing we learned really in Zapotec was how to drink.
[phonetic Zapotec] “Los-en chute juba umbali.”
[phonetic Zapotec] “Kee-in juba umbali.”
Drink up. But I am curious how you convinced folks to give you a urine sample, to participate in your study, to even begin to comprehend what it was that you were trying to do.
Sure. So, you know, anthropologists have been working with the Hadza community for decades now. You know, that goes back to the 1960s even.
And so they’re used to people showing up in Land Rovers and saying, ‘Hey, I’d love to hang out with you guys in your community for a few weeks. And do you mind? And here’s what we’d like to do.’
And they understand, too, that they’re a special community. I think the closest thing we have in the States is something like the Amish, right, who are very aware that the people that they live around are not Amish, but who are very proud, and rightfully so of their lifestyle and want to maintain that culture.
And so, you know, in the same way that the Hadza know that other groups around them are not hunting and gathering, they know that that makes them special. And they understand when somebody says, look, you know, this is so unique what you’re doing. We’d love to understand, how do you make it work? How do you make a living doing this?
So having people follow along on hunting trips or on gathering trips or, you know, we often write down and weigh the foods that come into camp, for example. And we, of course, we explain all this and we ask permissions to get all and we compensate them for their time, to say too. We’re not just, you know, taking advantage. And so they’re kind of used to folks wanting to come up and work with them.
This particular study of asking for urine samples, which is part of this isotope tracking technique we use to measure calories. Look, if you can explain, look, we want to understand how your bodies use the food that you collect to burn off by walking, moving, surviving.
They get that immediately. I mean, that’s an easy conversation because it’s a calorie economy, right? They’re used to, they know that they have to wake up in the morning and get those calories. They know that their bodies are burning them all day. Of course, they have not had any formal schooling, many of them, or not much, but just intuitively they understand that. And so that’s actually a pretty easy conversation to have.
The urine, you know, anytime you get asked for a urine sample in a doctor’s office, anything like that, that’s always a little weird. I imagine it’s a little weird for them too, but they are able to understand that for sure.
And did you eat with them? And if so, what were you eating and how was it?
So we bring our own food because we don’t want to, you know, burden them by expecting them to sort of feed us. But I have tried a number of Hadza foods: zebra, you know, different kinds of antelope, all the different kinds of plant foods, the tubers, the berries. It’s all pretty good, I guess.
I don’t know, it’s not very flavorful. They don’t really use much, you know, there’s hardly any spices or anything like that. Salt is one thing that we actually use to compensate them because it’s what they would trade for, but they’re pretty sparing with it. So it’s not like a typical steak you’d get here at a restaurant in the States, something like that. It’s pretty, you know, tough. Often it’s a few days old. They don’t have any refrigeration, right?
Often they’ll, they’ll, so if it’s a big animal, like a zebra, they’ll eat a lot right when it’s killed. Of course, they cook their food, but then the stuff that’s not eaten gets cut into strips and hung over tree branches to kind of dry.
So it comes out a little bit like jerky.
A little bit. A little too soft and pink for my taste, frankly. But, you know, I’ve never gotten sick eating Hadza food, I’ll say that.
One of the topics that you broach in your book, “Adaptable,” is how our lifespans affect our health. And you describe the results of the famine that the Dutch suffered at the very end of World War II when the Germans were punishing the entire population.
And there was tremendous famine. Babies born during that time had a different health career than babies born before or after. Can you tell us about that, please?
That’s exactly right. So the context is, you know, you’re in the Netherlands in World War II. They get cut off from all food supply into the country. And, you know, people are starving. And mothers are starving, too, of course. Pregnant mothers are starving.
And that experience of starvation in the womb affected those babies into the whole course of their whole lives. So those babies are now, they’re born in the 40s.
So they’re 80 or getting close.
Something like that, now. Right. And people have been tracking their health outcomes since the 90s, at least. And so we know that those babies born in what’s called the Dutch hunger winter were more likely to develop heart disease, cancers, other medical problems that you normally wouldn’t assume have anything to do with you know, what happened in the womb, right?
These are things that manifest in your 60s, 70s, 80s often. And you think it’s lifestyle and your adult choices that you make. And of course, we know that it does affect it. But there is an echo of what happened very early in life, that somehow that programmed the way that their bodies are working.
Well, I think we’re talking about epigenetics. And I’m curious as to whether or not those changes were passed on to their kids.
Yes! So that is the big question. So epigenetics is, if people haven’t heard of that or heard the term and don’t know what it is, basically your genes aren’t getting changed themselves, but they’re getting turned on or off.
So there’s these little chemical markers that will turn a gene off or even can also turn it on. And those epigenetic changes are the environment kind of pushing your genes around. And so we think that’s happened to the babies that were born in the Dutch hunger winter.
And we think it was passed on to their kids because those kids are now often in their 30s or 40s, right, that generation. And we do see higher BMI, some more obesity in that group. These are now the grandkids of the mothers who were starving in the 1940s, right? So their grandchildren are showing some effects of this.
One particular event over the course of one year in the 1940s, we’re seeing those. Again, it’s sort of an echo of the past in the way that these people’s bodies are working today.
So what lesson can we learn from that experience?
Well, there’s so much to learn from that. One is that our environments affect the way our bodies work probably more than we appreciate. And it doesn’t just affect, you know, did I eat too much or did I exercise enough?
Those are ways that we know that we can affect our environments. But they can also, our environments can affect the way our genetics are expressed. And those effects can last at least a whole lifetime and perhaps even get passed on.
So what that means from a kind of societal point of view is that, you know, let’s think about trying to solve, you know, health differences between communities here in the States. We have people, you know, minorities, other groups who have been disadvantaged. And we try to, there’s a big civil rights, of course, movement to try to address a lot of that in the 1960s.
We might think, oh, well, you know, we fixed those problems in the 60s. So by now, everything should be fine. No, because if something that happened in the 60s can be echoing, sorry, if something that happened in the 1940s can be echoing still today, then surely things that began to change, of course, it didn’t completely change in the 1960s.
We can still be dealing with those environmental effects, even though we’ve done a, you know, we can be happy with the progress we’ve made. But it’s not going to erase the past in a way that we often think it might.
And we know we still have food deserts and so forth. So that is probably still having an impact.
For sure. For sure. And so, you know, it isn’t just one thing, but that’s right. So we have to be aware, of course, the modern environments, of course, but, you know, also cognizant of these past effects that we’re still dealing with.
So this is a little off track, and you may not have an answer. I think of you as anthropologist slash biologist because you really do pay very close attention to the biology of calories in and calories out and exercise and all the rest of it. What about psychology?
The Hadza, in particular, it’s a very close-knit community, and there are social interactions. And I’m curious about how that experience during the end of the Second World War affected people, not just biologically, but psychologically, and how that might be passed along epigenetically.
Yeah, I’m glad you brought that up. I often wonder how much the kind of the psychological health of the Hodge community, which seems to be very robust, very good, plays into the fact that we don’t see heart disease there. We don’t see diabetes there. We don’t see obesity there.
You know, the factors that we know can push people to overeat and develop other unhealthy habits here in the States, loneliness, stress, you know, feeling of being kind of left behind and it’s kind of social inequality, that kind of thing. We know that those are factors that push people to make unhealthy choices.
We don’t see those in a Hadza camp. You don’t see that in a community that’s egalitarian. Right. Nobody really has more than somebody else. Those differences are really small. They’re socially connected. You never go a day without having a good conversation with somebody you’ve known for a long time. You are physically active in getting the health and psychological benefits of that activity every day.
You never feel like you’re alone or left out. And those are all really important, too. And it’s not something that my research focuses on. But, of course, you can’t help but be aware of that when you’re there.
My last question has to do with how your research, how your interaction with people all over the world has impacted you personally.
It has made me just feel incredibly lucky both to be able to have those experiences. I mean, I can’t imagine a better job, but it also makes me feel really fortunate to be here in the States.
You know, I mean, I think we have a lot of debate and angst about the state of things in this country today. And I get that. But I feel a lot of those things, too. But we are pretty darn lucky to be here and to have the resources available to fix a lot of these issues and deal with them. And so it makes me optimistic and happy to be where I am.
Dr. Pontzer, I have to tell you that our time in Mexico was magical. We were there for almost two years. And it changed my attitude and perspective about a lot of things. And I thought a lot about Peace Corps volunteers and other anthropologists who travel the world and hang out with people in all kinds of different places.
And sometimes I think, you know, if we could just give people that experience so that more Americans could see the world maybe from a slightly different perspective by just hanging out with people, whether it’s the Hadza or whether it’s somebody in New Zealand or, you know, the Maori, whatever, that it might change the way in which we think about the other and ourselves.
Have you had an opportunity to reflect on that?
Absolutely. And I think it’s one of the things I try to share in my writing and in my classes I teach and opportunities like this is to kind of share that broad perspective that you get from travel.
And again, when you go to these communities, you have a chance to live there for a while. At first you notice the differences and then you notice all the shared humanity and you bring all those threads and those pieces back with you and you see home again in a different way right that’s I forget what the famous line is to travel is to come home and see it with new eyes something like that and i think that’s exactly right you know maybe we could do a better job making that a possibility for more folks here in the states or maybe uh social media will do a good job advertising the rest of the world to everybody. I’m not so optimistic about that.
But no, I agree with you that travel really makes that, broadens your perspective on this and gives you a new appreciation for what you have here and also what we can sort of learn.
Well, certainly Americans are not going to be able to eat the way the Hadza eat. We are not going to go out and dig up tubers that we will be consuming as our main staple.
No, that’s right. And, you know, not only that, but you couldn’t live like that. We couldn’t live on wild foods if we wanted to because there’s no wild foods in your supermarket.
Exactly right. And there’s not enough wild land for us to collect wild foods from, even if we knew how, which we don’t, most of us. So what should we be doing for our health and to maintain a healthy weight?
No, that’s right. I really appreciate you bringing that up because, you know, the importance of doing this work across cultures isn’t that we’re going to somehow, you know, try to bring those cultures home, right?
Every culture kind of fits into its own space. We don’t have to pretend to be hunter-gatherers. What we do is we have to learn the lessons that they’re teaching us. And the lessons that populations like the Hadza are teaching us are these. You know, try to eat whole foods that you recognize as whole foods.
Try to stay away from the, you know, modern engineered foods that push us to overeat. Make sure you’re getting physical activity every day. Anything counts. It doesn’t have to be the kind of things that they’re doing. Any activity is good activity. And, you know, that sounds simple and it sounds like the story you’ve heard before and you probably have.
But I think, you know, what this does is it clarifies, okay, the exercise is good for a lot of aspects of our health. The diet is what we really need to focus on for obesity. These are two different tools for two different jobs.
And if we can’t pronounce those chemical names on the label, and there are like a dozen of them, maybe we should avoid those foods.
Yeah, people always ask, well, what’s an ultra-processed food? And, you know, I think, well, if it’s got a shiny package and an advertising campaign, it’s probably an ultra-processed food. And if the ingredients list is a paragraph long, that’s another clue.
Yeah, that’s a pretty good clue. Dr. Herman Pontzer, thank you so much for talking with us on The People’s Pharmacy today.
You’ve been listening to Dr. Herman Pontzer. He is Professor of Evolutionary Anthropology and Global Health at the Duke Global Health Institute. Dr. Pontzer is the author of “Burn: New Research Blows the Lid Off How We Really Burn Calories, Stay Healthy, and Lose Weight.” His latest book is “Adaptable: How Your Unique Body Really Works and Why Our Biology Unites Us.”
Lyn Siegel produced today’s show. Al Wodarski engineered. Dave Graedon edits our interviews. B.J. Leiderman composed our theme music.
This show is a co-production of North Carolina Public Radio, WUNC, with the People’s Pharmacy.
Today’s show is number 1,449. You can find it online at peoplespharmacy.com. At peoplespharmacy.com, you can share your comments about this episode. You can also reach us through email, radio, at peoplespharmacy.com.
Our interviews are available through your favorite podcast provider. You’ll find the podcast on our website on Monday morning. In the podcast this week, there’s some information that would not fit into this broadcast.
You’ll hear about a healthy relationship with food, as well as what it’s like to work with the Hadza. How did Dr. Pontzer convince people to provide urine samples? We also discuss how food deprivation at certain critical points in life, such as in utero, can affect health in adulthood and even the next generation.
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