Are GLP-1s the Solution to America’s Obesity Epidemic? Fmr FDA Chief Explains

HARI SREENIVASAN: Bianna, thanks. Dr. David Kessler, thanks so much for joining us. Your new book is titled “Diet, Drugs and Dopamine: The New Science of Achieving a Healthy Weight.” And you’re looking really kind of a little bit more holistically at nutrition and weight loss. And I guess, why did you feel the need to write this book right now?

DAVID KESSLER: You know, the American body is ill. Only about 12% of Americans are metabolically healthy. And there’s a real opportunity to reclaim our health. That’s why I wrote the book.

SREENIVASAN: I mean, how much of the population is, you know, suffering in these different ways. I mean, our, our statistics say that we’re talking as of 2023, 40% of American adults over the age of 20 are considered obese. How did we get to this point? I mean, is it, is it the fact that ultra processed foods have been introduced to diet, how long they’ve been there, how culturally accepted they are?

KESSLER: You know, let’s understand one thing. This is not about weight. It’s not how big you are or small you are. To me it’s about health. The question is really about toxic fat, sick fat. It’s the fat in our midsection. It’s the fat that gets into our liver, into our pancreas, right. Into, you know, layers of our heart. That cause, you know, many of the chronic diseases: cardiac, kidney, metabolic, certain forms of cancer and possibly even neurodegenerative diseases. So it’s toxic fat. This is not about weight.

SREENIVASAN: Can you explain a little bit medically, what’s happening with that kind of belly fat or deep fat, visceral fat, whatever it’s called? What is it actually doing? How is it kind of actively working against my health? More than just the fact that, oh, I have a few pounds now overall spread out from my body. What’s the danger of it being right here in my midsection?

KESSLER: You know, this midsection fat as you just referred to it, this toxic fat, it’s different than some of the fat that’s under our skin and our arms and in our legs. This fat, these fat cells have a hard time because of the just amount of calories we’re taking in, holding on to all the lipids, to all the fats. So they leak these molecules, they leak certain pro-inflammatory molecules. And those molecules in that fat, I mean, are getting into our vital organs. You know, doctors, whether it’s cardiologists, nephrologists, neurologists, oncologists, we’re all waking up to the fact that this toxic fat getting into our vital organs, that our organs are bathed in this inflammatory soup that these cells are, are leaking out. I mean, it’s, it’s really causing metabolic chaos in our bodies. You know, this, this beer belly we always, you know, became part of the culture. You know. Thought it, thought it was cool, you know men were, were strong. I mean, it’s really killing us.

SREENIVASAN: You know, if you, if you look at this as an addictive set of substances that are causing the worst of this midsection and toxic fat, I mean, should we be looking at this as something that’s able to change our brain chemistry?

KESSLER: You know, I, I think we go all relate to the experience. I mean food is, food is very powerful. Whether it’s neurochemistry or the neuro circuits, you know, I think we need to rethink how we talk about addiction. You know, addiction was always something, you know, that was the, the weak, the downtrodden. In fact, these addictive circuits are, are part of all of us, you know, thousands of years ago, you know, our brains evolved to deal with an environment of scarcity. I mean, <laugh>, the, the brains that could focus our attention, I mean, on finding this energy dense food in an environment of scarcity. I mean, that was great for survival. It’s not that our brains today are not working well, or something’s broken about them. They’re working only too well because we’ve changed this food environment to put these energy dense foods. I mean, through, you know, 24-7, we’re exposed to it. 

You know, there are certain elements of addiction there. There’s something called cue Induced wanting, what’s a cue? It could be the time of day. It could be I passed a, a certain store. It could be a, a smell. I wasn’t even thinking about it. But my brain unconsciously, get cue, gets cued, and based on past learning and past memory, that cue stimulates this, this wanting. And all of a sudden, I have thoughts, maybe I should go into that store. Maybe I should have that food. I mean, and until you you know, actually consume it, those thoughts stay with you. And you know, if, if you have the food available 24/7, you don’t even feel the pull, I mean, of these. But when you try to resist. I would always lose weight. I’ve gained and lost my body weight multiple times. I would lose my, lose the weight. I was done. You know, I thought, and I would always gain it back. I mean, one of the, the things about addiction, I mean, there’s relapse. And when you’re dealing with food, I mean, it’s really about that, that regaining food. Yes, there’s metabolic adaptation, but these reward circuits, I mean, they’re just part of all of us.

SREENIVASAN: So if this is an addictive substance, and it’s engineered to be more so, what’s the role of the government here? Should this industry be regulated more closely? We’re doing it for alcohol and for tobacco.

KESSLER: I have the privilege, you know, of being part of the team that, that, as you said, you know, did the investigation into tobacco. No doubt that there are certain tools the government has that can change our relationship with these addictive substances. But what really worked in tobacco? What – I mean, it was one of the great public health successes. I mean, over the last hundred years, you know, at the turn of the previous century, what the tobacco companies did was you know, the, they hired the psychoanalyst, AA Brill to come up, you know with the phrase, you know, symbols of liberty, torches of freedom. There was the march down Fifth Avenue you for, for emancipation. They made cigarettes into something that was sexy, adventuresome, glamorous. There was the Marlboro man. I mean, they made it positively, valenced. And what happens when something’s positively valenced and it’s addictive? I mean, you want it.

 What did we do over the last 50, 75 years, right? We changed the valence. We, we, we changed the, the tobacco. It was this critical perceptual shift from something I wanted. There was my friend to something that I didn’t want. There was a deadly, disgusting product. It was my enemy. So how we perceive these foods. Are these foods really satisfying me? What are they doing to my body? Do I really want them? I mean, I think, yes, there’s government tools that you can use, but we really have to change how we see these foods.

SREENIVASAN: Let’s turn our conversation a little bit to GLP-1 drugs. And you write it really in, you know, in a fantastic kind of personal voice about your personal journey with these drugs. how do the sort of Semaglutides the Tirzepatides, how do they work? And what has been your experience with them?

KESSLER: What they do is, the scientific term is, they delay gastric emptying. That, that just simply says that food stays in your stomach longer. And we all have experienced that. You know, we get the flu. Our GI tract doesn’t move a as much, food stays in our stomach. And how do you feel? You, you don’t wanna put anything else. I mean, in your stomach. I mean, there is this spectrum, you know, there’s this, there is and it’s the result of both the GI tract and, and part of the brain, the hind brain. You, you know, that continuum of I feel satisfied, I feel full, and then it, this thanksgiving fullness. I mean, everybody perceives these differently, but for me, they took me to the edge of nausea. What’s strong enough to overcome the addictive circuits, right? I mean, there are another set of circuits in the body called the aversive circuits. You know, the, the circuits that, you know, when we feel ill, in fact, when the first early you know, precursors of these drugs were given to laboratory animals, the animals didn’t move. The scientists, you know, coined the term visceral malaise, this general illness. 

And what the great thing is about these drugs, because of the dose, they can push you along that continuum. You know, fullness, satiety. I mean, some people can’t tolerate these drugs ’cause they, they push them over, I mean, into outright nausea. But those feelings are strong enough to, you know, overcome the reward circuits. 

The problem is, these drugs only work while you are on them. And the latest data that I saw is that the average person in this country is on them for eight or nine months. You go off them. I mean, and they stop working. But the premise of the companies are that you’re gonna be on that for, for, you know, your life. I think that the FDA and the companies have to study how we can effectively use these drugs in the real world. 

SREENIVASAN: You know, you’re describing a couple of different processes here. One is kind of the physiological, if there’s more food in my stomach and I feel full, I don’t feel like I’m gonna put more calories in. Right? And then the other is, what’s interesting to me is, kind of this idea of food noise, right? Decreasing your interest in going after all foods, including the hyper addictive ones. So I wonder when you got off the drugs, did that food noise increase? 

KESSLER: You, you said it very well. You know that food noise is the result of those reward circuits, those addictive circuits. I mean, that, those are just the, those that cue induced wanting, you know, I been going off in my head that my reward circuits, I mean, are being triggered. And those aversive circuits – that, that edge of nausea that I felt, that, you know, the sort of counterbalanced those addictive circuits – that works when you’re, when you’re on these drugs and they’ll work for a while after you go off them. But at a certain point, you know, this is highly variable. I mean, we’re each, you know, every individual has their own experiences. For me, I mean, it worked for a while, but what I’ve found and what I’ve tried to do is to change my relationship with food while I’m on that, what I want and try to have that sort of condition me in a way to be able to carry over.

But, you know, I mean, I, I had the opportunity to run, to co-lead Operation Warp Speed. I mean, during the, the, the pandemic, I, I worked 18 hour days. I was sitting there at my, my computer. I didn’t get up – you know, it was seven days a week. And I turned around and I was some 40 pounds heavier afterwards. You know, and I, I wanted to, to do something about this. I mean, these drugs are not a panacea, right? I mean, there’s no magical – they’re one tool, right? You need to take them. I mean, you, you can’t expect to deal with these addictive circuits by yourself. You need a team. You need a good physician. You need a, a dietician. I mean, you, you need people who can help you to change the relationship with the food. And, and, and the drugs are one tool, but only one tool.

SREENIVASAN: You know, we are having this conversation about these drugs. One of the things that I definitely wanna point out is that, you know, we might have access to them, but it’s very unequal access. For most people, their insurance does not cover the GLP-1 drugs. It might cover it for diabetes, but it might not cover it for weight loss. 

KESSLER: This is not about willpower. This is, this is very much a disease process at work. And it’s causing enormous – trillions of dollars of health bills these insurance companies are paying. I think one of the first things the administration has to do is to agree under Medicare to cover these drugs. Not to do that is a form of discrimination against people who live, who struggle with obesity. 

 We need to provide access to the, the, to these drugs. I, you know, I carried, I was carrying three different insurance policies, and not one covered these drugs. They were, you know over a thousand dollars. I mean, could you imagine struggling with your weight your whole life and being ill from it, from suffering, the cardiac consequences, the renal consequences, you know, pre-diabetes, diabetes, you know, and a number of other complications. A drug comes along and it can help you, and you can’t have access to that drug. 

I mean, it, it, it just shows you how broken the American health system is. The companies, what do they do? They, they price these drugs, you know, exorbitantly. And there is this thing in the food and drug laws that’s sort of this loophole that allows what’s called compounded drugs to be made. I mean, these are drugs, you know, not coming from the manufacturers, the source of these drugs probably coming from China, it’s hard to even know where these are, in some cases, being made. The FDA has not done testing to assure the safety. So because the drug companies had priced this, these drugs so high, people had a resort to drugs that they couldn’t assure the safety of. Now the companies are lowering their prices to compete with these compounded drugs. I mean, that, it just shows you how broken the healthcare system is.

SREENIVASAN: So, is there something where we can collectively figure out how to increase access to this category of drugs, while at the same time, I don’t know, equipping people, preparing people for a way for them to say, okay, this is – we understand that the manufacturer says, you need to be on this drug for the rest of your life, but our goal is not to have you on this drug for the rest of your life. I want you to just figure out in this interim, like, let’s get you back to a healthy level. And hopefully between now and that point, we can change your relationship with food.

KESSLER: You, you’ve just said it wonderfully. I mean, that, that’s the goal, but it’s a journey. There is no end game right now. You and I are not gonna figure out you know, how to use, get the data to use these drugs, the right dose whether it’s safe to take that dose down. Can you, can I go off the, the drug? When can I go back? Will it continue to work? Those are questions the drug company, along with the regulatory bodies, need to figure out. What our job is to do, is to want to be able to deal with this toxic fat, with this sick fat, to, to reclaim our, our, our health. And to get a team I mean, again, access is a very key issue. Can’t, you can’t deal with an addictive substance alone. You, you, you need docs, you need nutritionists. That’s what we need to do. We just have to wanna reclaim our health and understand there’s no end game. It’s a real journey.

SREENIVASAN: Former FDA Commissioner, Dr. David Kessler. His new book is called “Diet, Drugs, and Dopamine: The New Signs of Achieving a Healthy Weight.” Thanks so much for joining us.

KESSLER: Thank you.