ZOE Science & Nutrition - Recap: Is the new obesity medication too good to be true? | Dr. Louis J Aronne

Episode Date: July 2, 2025

Today we’re talking about obesity medication. Did you know that over 200 illnesses are linked to unhealthy weight gain? It's no surprise that combatting obesity has become a major focus of modern medical research. In recent years, this research has led to a new generation of weight-loss medications that are delivering dramatic results. But are these drugs truly revolutionary or just too good to be true? One thing is certain - people have a lot of questions. Today, I’m joined by Dr. Lou Aronne to help us separate the hype from the hard facts. 🥑 Make smarter food choices. Become a member a zoe.com - 10% off with code PODCAST 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free resources from ZOE: Live Healthier: Top 10 Tips From ZOE Science & Nutrition  Gut Guide - for a healthier microbiome in weeks Have feedback or a topic you'd like us to cover? Let us know here Listen to the full episode here

Hello and welcome to Zoey Recap, where each week we find the best bits from one of our podcast episodes to help you improve your health. Today we're talking about obesity medication. Did you know that over 200 illnesses are linked to unhealthy weight gain? It's no surprise then that combating obesity has become a major focus of modern medical research. In recent years, this research has led to a new generation of weight loss medications that are delivering dramatic results. But are these drugs truly revolutionary or just too good to be true? One thing is certain, people have a lot of questions.

Today, I'm joined by Dr. Lu Aron to help us separate the hype from the hard facts. I did the first study looking for anti-obesity medications in 1989. More than 60 trials of obesity treatments in my career. And it's pretty clear that these are breakthrough. This is the beginning of the breakthrough. This is not the end. This is just the beginning. The breakthrough is not only the level of efficacy, which it's clear people find is terrific and enjoyable and changes their lives, but also the tolerability of these medications.

So we've had medicines that are not quite as effective, but they are effective. The problem was, in many cases, the side effect profile and the risk associated with those medications. But now we have things that are not only effective, but easy to use. One shot per week is pretty well tolerated. And I think that this is a pivoting point in the treatment of chronic metabolic disease, that people are choosing to treat their obesity, which is the cause of their diabetes, their hypertension, their high cholesterol, their sleep apnea, their knee arthritis, and the list goes on and on.

And lecturing these days, I have a slide I made where I've characterized treating obesity as the Superman of treating metabolic disease. Literally 200 illnesses can occur as the result of increased body weight and treating obesity makes them all better to a certain extent. It may not cure them all, your blood pressure may stay up, your cholesterol may not cure them all. Your blood pressure may stay up. Your cholesterol may not go down. All of those things can occur, but there is no treatment for any of the others that treats something else.

But by treating the obesity, you get them all. It may not go away, but it tends to get better. And so I think that we're going to see people choosing to treat their weight rather than wait until they develop all of these complications. And, Lou, I know you're also researching a whole set of sort of new weight loss drugs that are not yet available for prescription. What can you tell us about those? Because I understand that they may be better still than the drugs that are available today. Yes, I think that what we're going to see is on one hand, increasing levels of efficacy. If we look at the second drug that

has been approved in the United States, Terzepotide, which is known as Mungaro for diabetes and in the U.S. for weight loss, ZepBound, that produces even more weight loss than some agglutides, Ozempic or Wegovi. Where those drugs produced about 16%, 17% weight loss in the highest dose, terzepatide produces 22, 23% weight loss. I mean, that's amazing. These are enormous numbers. If you look at the next generation of medications,

they're going to produce between 25 and 30% weight loss, and in some cases, we haven't finished these studies yet, but I bet they're going to produce even more than 30 percent weight loss. So these next generations are dramatically better than the sort of Zempik that we're all hearing about. If this is going to cure this disease of obesity, does that mean that everyone should just continue and can continue to eat

sort of all this ultra-processed junk food and they're now going to live as many healthy years as they would do if they were on a different diet? So the short answer is I don't believe so. But when you use these medicines, it helps people to comply with a diet. I think that's really powerful. It's one of the things that I've been wondering a lot about because we know how much challenge there is for a lot of people to be able to manage

what they're eating. Right. So not everybody is going to do that, but we work with registered dietitians. They love these medicines because they say, finally, my patients listen to my advice. I tell them to eat healthy proteins, vegetables. We work out a plan and they're like, oh yeah, I can do that. It's not a problem. And Lou, one of the things I understand is basically you have to keep taking these drugs forever. If you stop, then you will go back to that set point you were describing.

Is that right? And is there any evidence that you might be able to shift your diet while you're on these drugs towards something much healthier and that then you might, for example, be able to come off them and not sort of shoot back to where you were before? Not everybody gains all the weight back. About one in six people can maintain at least 80% of the weight loss.

So if they lost 20% of their body weight, they could maintain at least 16% or greater weight loss. So if they lost 20% of their body weight, they could maintain at least 16% or greater weight loss. And if you look at the rate of weight regain when you stop the medicine like this, it's roughly one to 2% of the initial body weight regained each month. We just published a study where we got patients on terzepatide.

They lost 21% of their body weight over nine months. And then we either continued the medicine for a year, in which case they lost another 5% of their body weight, or we stopped it for a year. And over that one year period, they regained 12%, 1% per month of the initial body weight. So they were still down between 9% and 10%, one year after stopping the medicine. So what my conclusion from studies like that is that you could use it intermittently, perhaps. Take it for a month on, a month off. I think that those kinds of strategies will be used.

There are studies now showing that semaglutide, as Wegovi, reduces the risk of a heart attack, a stroke, and death by 20% in people who have heart disease. That's just like using a statin drug. But in addition, it also reduced the risk of developing diabetes by 73%. And that's because these were people who were living with obesity,

and then that was such a high risk, and you'd take that away and it just- That's right. So they did not have diabetes. They didn't have diabetes when the study began. So in addition to getting the reduced risk of heart attacks, strokes and death, you also got a reduced risk of diabetes. You also got a reduced risk

of developing kidney failure. So they sound pretty magical when you describe this. I think a lot of people are listening to this saying, well, that's great, but I can't get it right now. Either it's not available in my country, or I can't afford it, or whatever. How do you imagine accessibility? Imagine we're in five years from now. What's your guess about accessibility? And in 10 years, is every single adult human being

going to be taking these? There are more than a dozen compounds that we will see within the next five to seven years that are in development and later stages of development and will become available. That should reduce the price and increase the availability. If we look at examples of other chronic diseases, hypertension being the first.

Back in the 1970s, we knew that hypertension could give you heart failure, strokes, etc., but the treatments were not very good. They had a lot of side effects, and they weren't used very regularly. But in the early 1980s, a whole group of drugs was discovered that were very accessible. Primary care physicians could use them because they were very tolerable and not very complicated. And since that time, hypertension has become treated everywhere. What we've learned with chronic diseases like this, cholesterol being the second big example, is that if we treat early and prevent things from getting worse, that's really the best way to go.

And so Lou, one way of saying that would be, you would give these drugs to everybody as soon as they were, you know, two pounds heavier than they were when they were 21. I guess personally, it feels bad to me. I feel like we haven't been living with obesity forever. This is a consequence of our environment. I think in particular, the food, let's say you're listening to this. You're like, that's not what I want to do is are we in a world where sort of this

living with obesity is inevitable or actually do you believe that if you hit it before this damage is done and you sort of above all change your diet that you can avoid that what is your perspective? Sure, you can avoid it. So if you do that and if you want to do that, you are welcome to do it. So when people come to see us, we do not make them take medicine. It's entirely up to you. us, we do not make them take medicine. It's entirely up to you. But if it doesn't work and you develop these kinds of complications that we see,

my advice would be to take the medicine rather than to wait until things get worse. So I don't want you to think that I am advocating for everybody. You know, this should not be in the water supply in high schools. But changing the food supply is more difficult than you may think. And I would urge you to try it if you think it's possible. Very final question. There are clearly a lot of people who are taking even these first generation drugs, who are not living with obesity, who I think don't fit your definition, medical definition of overweight.

Do you have any concerns about that? Because you were describing in general how well tolerated this drug is. Like, what are your thoughts about that? So I just saw on the way over, you know, an actress was using the medication, was talking about Ozempic, but she had no weight problems. And so my feeling is we should not conflate the misuse of these medicines by actors and actresses

and other well-known people with the incredible benefit that is being seen by people with the disease of obesity. I mean, I can't tell you how grateful our patients are and how freeing it is to have something that finally works. I mean, it's just amazing because we train doctors at all levels and they're thrilled seeing patients with us. They cannot, so, you know, the young doctors, the residents or fellows or students are like, this is unbelievable. I never saw anything like this.

I've never seen people who are so grateful for relief from what they had to endure. You know, those are the kinds of things that we see. for relief from what they had to endure. Those are the kinds of things that we see. So I think that that is being obscured by people who don't need to lose weight taking these things. But make sure that those are not confused. That's not the use of these things. That is what I would call misuse, which we do not encourage. If you look at people who really need these medicines, this is liberating. This is like the biggest change in their lives that has

ever occurred. I hope you found the information in this week's episode useful. If you're interested in improving your gut health, you might want to download our free Gut Guide. It's packed with recipes and science-backed information to help you on your journey towards better health. Go to zoe.com slash gut guide to download it for free. Or if you're looking for another podcast to listen to, we have a lot more in our back catalog.

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