'When I was in residency, I had a Black woman patient who was in her mid-forties that I had been treating. And I happened to run into this particular patient as she's about to check out at the grocery store. She's like, "hey, Dr. Stanford. I'm like, hey."

That's Dr. Fatima Cody Stanford. She's an obesity medicine physician and a scientist at Massachusetts General Hospital in Boston. She's also a professor at Harvard School of Medicine. Now, she said she'd been caring for that patient for three years at that point. But the day Dr. Stanford saw her at the grocery store, that particular encounter. Well, that changed everything.

'I have, the ability to do something that most doctors aren't able to do at this very moment, which is to see exactly what she's about to check out with at the grocery store line. But I'm trying to be inconspicuous in this observation. We had spent all of this time over the last three years, you know, really going over what she should be purchasing, what she should be eating, what her diet should be looking like - lean proteins, whole grains, fruits, vegetables, minimally processed to no processing, all of these things. And she says to me, "Dr. Stanford, see, I told you, I've been doing everything you told me to do." And when you looked at her grocery cart at this very moment, it was the picture perfect grocery cart. There was nothing I would swap out.

Dr. Stanford says this experience made her reevaluate the entire way she thought about obesity. It made her check her own biases, and it also started to make her think differently about why her patients really struggle to manage their weight.

And it was at that moment that I recognized that I made assumptions about what she was or was not doing, because in those three years that we had worked together, there have been minimal shifts in her weight. And here she was, doing the right things, doing the hard work, making the right choices. But her body just wasn't responding in the way that that someone else's might. But on the surface, the assumption would have been, is she really eating the right things? Is she really putting in the hard work?

'In fact, the story continues. A few weeks after the grocery store encounter, Dr. Stanford learned that the patient who had been diagnosed with severe obesity was not only eating healthy, but she was also exercising regularly. In short, she was doing everything she was supposed to be doing. She was doing all the things patients who are overweight are told to do, but she wasn't having any results. Now, this story may sound very familiar to you, and that is exactly why I wanted to start with it. Think about it. You see someone who is overweight and you think to yourself, if only they ate, right? If only they exercised. And sure, sometimes that might be the answer, but not nearly as often as you might think. I know at the start of every new year, a lot of people are thinking about their health and in many cases, thinking specifically about their weight. So I wanted to give you some statistics to get us started. Almost 31% of adults in the United States are considered overweight. More than 42% have obesity; 9% have severe obesity. All those numbers are from the 2017-2018 data from the National Center for Health Statistics. What they basically tell us is that 3 out of 4 U.S. adults are considered overweight or have obesity. Think about that - 75% of Americans.

'So it's probably not at all surprising, then, that a lot of adults in the United States say they want to lose weight. And maybe you've been thinking about the same thing. Losing some weight. Finding the right weight range where you look good and feel good. Maybe you're also wondering about these new medications - zempic, Wegovy, Mounjaro. Are they right for you? Whatever your goals are, I'm hoping this season can help you navigate a topic that is far more complicated than most people realize. More complicated than even obesity doctors realize. So we're not only going to learn the latest in obesity medicine, but also the basics of nutrition, evolutionary biology, hormones, metabolism, lean mass, fat mass. And today we're going to try and answer a fundamental question: which numbers actually carry weight when it comes to indicating good health. I'm Dr. Sanjay Gupta, CNN's Chief Medical Correspondent. And this is Chasing Life.

You know, as a neurosurgeon, I'm pretty comfortable talking about the human body and the human brain. But a lot of doctors really don't spend enough time talking about weight. Maybe it's still considered taboo, or it's still not clear what numbers besides the one on the scale matter the most. These are some of the reasons I wanted to speak to Dr. Fatima Cody Stanford. Now, if her name sounds familiar at all, it may be because Oprah, who has been very public about her own weight issues, recently turned to Dr. Stanford to discuss the topic.

The brain tells you a certain thing about how you process food versus the willpower. Can we talk about that?

Absolutely. Because this isn't about willpower.

Thank you for saying that; I mean...

I have talked about those pathways.

Just so shamed.

Right?

Every single week.

And it's not it's not it's not your fault because it's not in the pathways, you guys. It's just not in the science of this disease.

Now, before we sat down for the podcast, Dr. Stanford asked me to watch a talk she gave to the Radcliffe Institute of Advanced Study called: Obesity: It's More Complex than You Think. The talk is available online, and she says she asks all of her patients to watch it before a consultation. One of the big headlines of the talk is as important as asking someone how much they weigh. We should also understand how someone functions.

Our weight is one factor that plays a role in our health. It tells us how much excess, adipose or fat we carry, but by itself, it doesn't give us the full story of who we are. We have to look at our full person and our, ability to function and perform at our weight.

That made sense to me. But I was also curious what it really meant. For example, Dr. Stanford's patient from the grocery store was struggling with their weight, but was also clearly eating right and exercising regularly.

Let me ask a very fundamental question, doctor. Is that patient unhealthy?

So that's a very good question. And I think to really get at that, we have to look at several different things. So let's look at her weight. So she has severe obesity as classified by just body mass index which by itself is is flawed. And so you want to take a deeper dive to look at her metabolic health parameters. So her cholesterol values, her fasting insulin, her glucose, her liver function test, all of these things which were in some ways dysregulated. And so I would have said that if you looked at those in conjunction with her weight, there was some room for improvement. And so these more aggressive tools could have helped bring her into better metabolic health. But if those those parameters, those metabolic health parameters in conjunction with her weight were normal, then I would say, you know what, I'm happy with where she is. Despite her weight being in a higher weight class.

'I hope people sort of listen to this point, you know, on the podcast quite a bit because I mean, again, obesity in and of itself, I know your perspective is in and of itself can be a disease. Right? But what you're really looking at is the ramifications of that obesity - high cholesterol, triglycerides,.

Absolutely.

Your insulin's not working as well.

I can't streetcorner medicine. I can't just judge the book by its cover and assume that.

Right.

Someone that is larger is unhealthy, and someone that is lean is healthy, right? That's that's the assumption that people make. And I call that practicing "street corner medicine." We're going to we're going to coin that today on the show, Sanjay.

Street corner medicine. I like that.

I want to look beneath the the surface of the individual and see what's going on, because someone who's lean may be very unhealthy and someone who's heavier may be healthier. You may have someone who carries excess weight, they may be an ultramarathoner. They may be capable of running an 100 mile race and be very, very healthy, not have joint pains, may not be able to carry that weight and do things that someone that's much leaner, may not be able to, and have the metabolic health to fit that profile. And so I think it's important for us to look at the weight plus the health, and put those two pieces of the puzzle together.

For people who are listening, who say, look, I'm carrying around extra weight, but I get my blood work done. I'm diligent about that stuff. And my blood work, quote unquote, looks good in the sense that my triglycerides are not elevated. My glucose is fine. What would you say to that person? Is the excess weight in and of itself problematic?

No, I would say no. And so I have patients that carry excess weight that have no metabolic dysfunction. They have no mechanical dysfunction that I would say, or healthy individuals, maybe they, when they first came into me, had even more excess weight and did have this dysfunction and have moved into having less of that excess weight, not the degree they came in with. I don't know if you've heard my story about the train conductor.

Let's hear it.

When I first moved to Boston, I lived on the north shore of Boston, and I had to take this commuter rail. There will be this train conductor, a gentleman that carried a lot of excess weight, but he move up and down. He would take the tickets, kind of climb things, do all these things. And secretly I wanted this guy to be my patient because I could tell that this excess weight caused him a lot of mechanical stress. You could tell that, you know, just and diaphoresis, meaning he ate excess sweat. A lot of things that just, but due to the degree of excess weight, I couldn't tell how much excess weight he carried. But I could tell it was quite a bit. So fast forward into the future, 4 or 5 years later. And guess who's sitting in my office, you guys?! The train conductor! So I am like, oh my gosh, you're the train conductor. And he's looking at me like, I mean, he's obviously coming to see me as the doctor, but he doesn't know me. I'm just the smushed person in the train. But I want to point to the person who was most emotional in the room at this time. So this gentleman, late 40s at the time, there's a woman in the room who's a little bit older, and this woman is crying. So I now refocus my attention to her. And I realized that this is his mom. And she says to me, "no doctor has ever been excited to see him. He struggled with his weight since he was a young boy.".

When this gentleman came in to see me, he was 550 pounds.

Wow.

That was when I began to care for him. He's now about 300 pounds. He is healthy at 300 pounds. And so this goes back to the question, you might be like, where is this going? He no longer has metabolic dysfunction; he's able to actually move with ease at 300 pounds. But at 550 pounds, I could sense the degree of stress and strain that he had. But at 300 pounds this stress and strain is not there. But if you were to see him and you were practicing street corner medicine, because we're coming back to that, you would make the assumption without knowing anything, that you know what, that guy needs to lose weight. He needs to do something about his health, not knowing that he is 250 pounds less and has been treated for his obesity than he was when he first came in to see me. And so do you see where I'm going with this is that each person has whatever their right weight. And so when I say to my patients, my goal is to get you to the happiest, healthiest weight for you. And so this comes to this idea of not comparing yourself to the person next to you, the person beside you, the person above you, whatever that is. What is the weight that you best live at? And that's an important nuance that I think that if we can get that in our heads, that would make us a healthier society, not only here in the U.S., but around the world.

So I bet you're wondering how that train conductor lost 250 pounds. Well, the short answer it was not easy. Doctor Stanford says he used medications, a combination of therapies and also bariatric surgery, which basically changed his digestive system. So what does that all mean for you? When we come back, Dr. Stanford shares tips on what to do if you think you're overweight and why she hardly ever uses BMI or body mass index to measure health.

When you put this all together, Dr. Stanford, then how would somebody who's listening now figure out what is their ideal weight? We're going to talk about the whole sordid history of BMI in a second. But the ideal weight for anybody who's listening, if they're not just going to go online and check their BMI, like, what do you look for? What do you tell them?

So I never give my patients an ideal weight. So that frustrates people because they want an number. And I don't ever give them a number because I want to look at their whole health. And so I don't know what that number is. Let's go back to the train conductor. Nobody that I think that's a doctor is going to give 300 pounds as a number to a patient. Right. That that just sounds too high, but that's the number for him where he no longer has joint pain, where he no longer has high cholesterol, where he no longer has signs of fatty liver disease, where he no longer has sleep apnea. That's his number. And I didn't know that 300 pounds was that number for him until we got there. Right. So I can't really give you an ideal number until we treat the whole you.

People who are healthy by these measurements that you're talking about, their lab levels and their and they don't have joint pains and things like that, but they're still not happy with the way they look or what the number says on the scale. What do you say to them?

So this is when I bring in my mental health professionals. There may be issues with body dysmorphia. This idea that I still need to be leaner, even when we look at the individual and you were like, really, do you need to be leaner? Do we really need to push you into a norm?

And this is a topic we will talk about later in the podcast this season. But I would just say, and again, this is your expertise, but people should have grace with themselves. We're surrounded by all sorts of images that give people a sense of what they should look like, what clothes should fit, and what their body style and shape should should look like. And so, yes, they should have a little bit of grace with themselves and with each other.

Absolutely.

Should people look at their BMI?

So I think BMI is a a screening tool. I don't think it's a diagnostic tool. And I think that for so long we've used it as a diagnostic tool. And that's led to issues of creating this issue of inequities. The origins of BMI were not from medicine or science, by that I'll, I'll kind of...

From statistics, right?

Right they're from statistics. And so for those of you who are unfamiliar, Aldolphe Quetelet in the 1800s sought to determine what was considered to be normal for for Belgian white male soldiers. And then subsequently, that became the Quetelet Index. The Metropolitan then Life Insurance Company then used this to determine what was considered normal for insuring white, male and female populations. Hence the term morbid as it relates to obesity. So what was your risk of dying. And so that's where morbid as it relates to obesity came from. And then Ancel Keys in the '70s, um, came up with this idea of BMI. Oh, it's easy. Let's just let's just come up with this BMI and then we turn to determine these cutoffs. And then it's easy. And so notice this didn't come from medicine or science. But yet it's what we use to determine whether or not you are healthy or not based upon your weight. And so just because something's easy doesn't mean we should use it. I think it should just be a screening tool. And like I said, used in conjunction with other metrics to determine the health of an individual.

The fact that BMI, which is something that is a vernacular, it's quite well known not just in the medical community, but among everybody. But that was based off statistics from white male soldiers in Belgium in the 1800s. Just throw that in the back of your mind when you think about BMI, people who are falling outside of that particular community racially, their ethnic, ethnicity, whatever it might be, that that's who this BMI was originally focused on, which I thought was really interesting.

Not you or I, Dr. Gupta.

Not you or I. No.

No.

You've said that diet and figuring out how you nourish yourself can be very helpful, obviously, in terms of losing weight. When it comes to exercise and how you move, that may be better described as something that can help you maintain.

Absolutely.

I got that right.

Absolutely. You are 100% correct. And I think that this is really important, you know, think about gyms around the country, around the world. Everybody joins a gym. You know, gyms make all of this money as people enroll in new gym memberships. But let's think about how packed gyms are January. And then we see that trickle down and who's there by the time you get to maybe February 15th and then by March, you know, only the diehards are there because what did people go when they went in with a desire to lose weight and they went in. They were aggressive with their exercise. And when the scale didn't really budge, they got frustrated. And they stopped going to exercise because they realized that, wait a minute, I'm doing all this exercise. I'm going, I'm going hard with the desire to lose weight when on average, exercise is great for a lot of things, right? It can reduce our blood pressure. It can improve our cholesterol parameters. It can improve our, you know, liver function test. It can improve our mood. But on average it causes weight maintenance. So if you're going with the desire to really drive down weight, you're going for the wrong reason.

If someone who's listening, um, is concerned about their weight, concerned about their weight affecting their health.

Yes.

What should they do first?

'I would say first, if you've never thought about this, is to think about diet quality. And what do you do? So everybody's like, what diet should I try? I just think about basics. And this isn't whether you're vegetarian, vegan, pescatarian, you know, just whatever you might be. Think about this - lean protein, whole grains, fruits, vegetables. Does it look like what it looks like in nature? If it looks like what it looks like in nature, it's better for your body. You know, you don't have to to become virtuous, like my patient that we thought about, right, with her grocery cart overnight. You can do this gradually over time. You don't have to be award winning on day one. I would say another key thing is to think about that physical activity piece. I always say to my patients, find your soulmate workout. What is it that you enjoy doing? Do it. Do it every day because this is a life time commitment. Your body is going to be here for the rest of your life. I can guarantee it. If you've done all of these things in the lifestyle realm and you're still struggling with your weight, it's time to seek help from a professional. Who is that? I would say seek care from an obesity medicine physician. There are ways to find that. The American Board of Obesity Medicine has free access to finding professionals. You go to A-B-O-M dot org and you go find a physician and verify credentials. You can find it by your state, your city and state and don't, you know, feel judged by seeking out care beyond lifestyle. It's okay. You don't have to fit any one prescriptive, way of doing things. And if you don't feel like sharing that with someone, you don't have to. This isn't, you know, a judgment on how you're choosing to address your weight. I think you have to find the best way for you.

There's a lot of buzz around these weight loss meds and sort of, broadly speaking, they fall into three categories. Ones that affect your brain.

Yep.

Ones that affect how quickly, I guess food moves through your system, if you will. And then other ones. That sort of, I guess, increase your metabolism. So you burn the calories faster. Are you excited about there's several new weight loss drugs on the market. How big a deal is this in your world?

'I mean, it's I feel like it's a really big deal. You know, when I first started using anti-obesity medications, no one seemed to care. I mean, obviously, my patients cared because they were, you know, responding. But now the world seems to care.

'We're going to do a deeper dive into these weight loss or anti-obesity medications, as she calls them later the season. But what's important to note is that Dr. Stanford, someone who has dedicated her life to the disease of obesity, is optimistic about these medications. She doesn't see them as a fad, but rather as important tools to help her patients achieve their health goals.

'You know, when we talk about people struggling with their weight, we recognize that some people have tried many strategies to address their weight. And no matter what they've tried, their weight still maintains a high set point for weight. And so they become very frustrated and they feel like it's hopeless. And no matter what they do, there's no way for them to really address the degree of excess weight. But I want those people to realize that there's still hope. There are strategies that they may not have entertained, whether that's the use of anti-obesity medication or surgical interventions or behavioral strategies.

'Let me take a second to pull back the curtain. When my team and I started researching the topic of weight and health. We knew it was going to be complicated. Sure. It's about weight, pounds on a scale, how you look and how you feel. But the goal, I think, for most people is always to obtain optimal health. And we quickly realized that comes in all sorts of shapes and sizes. How much weight you carry around the midsection of your body may have a lot more to do with a small area in your brain, than you may realize why you feel hungry, why you feel full, and what you really do with all those calories that you eat and drink. I think it's important to share the science behind weight and how it can affect you, and what we've learned from Dr. Stanford and other doctors and scientists in the field has been really fascinating. They're advancing research around measurements that matter - blood sugar, cholesterol, liver function. And ones that don't tell us as much as we thought, like BMI. Right now, they're busy developing treatment options to help make weight management more sustainable. That means everything from psychotherapy to anti-obesity medications to surgery. And they're helping to shape the way we even talk about weight and obesity, like describing obesity as a condition, not a state of being. Most importantly, perhaps, Dr. Stanford encourages us to be aware of the assumptions we make about people who don't conform to our weight ideals. She says practicing what she calls, quote, street corner medicine, where we diagnose larger people as lazy or undisciplined or unhealthy on sight, alone, without really knowing anything about them, is not helpful, and it's often not accurate. And she reminds us that the connection between weight and health, between what we can and what we can't control about our bodies, is often more complicated than it seems. Next time on Chasing Life, we're going to talk to an evolutionary biologist about how our bodies actually evolved and why it makes it so hard for humans as a species to lose weight.

What we're adapted for, fundamentally, is not to be healthy, not to be happy, not to be nice, not to be, you know, not to be famous, not to be anything other than reproductively successful.

That's next time. Thanks for listening.

Chasing life is a production of CNN Audio. Our podcast is produced by Eryn Mathewson, Jennifer Lai and Grace Walker. Our senior producer and showrunner is Felicia Patinkin. Andrea Kane as our medical writer, and Tommy Bazarian is our engineer. Dan Dzula is our technical director and the executive producer of CNN Audio is Steve Lickteig, with support from Jamus Andrest, John Dianora, Haley Thomas, Alex Manasseri, Robert Mathers, Leni Steinhardt, Nichole Pesaru, and Lisa Namerow. Special thanks to Ben Tinker, Amanda Sealy, and Nadia Kounang of CNN Health and Katie Hinman.