Dr. Sanjay Gupta: What weight tells us about our health

(CNN) — If you’ve been paying attention to health news recently, you may have noticed a subtle but real shift in the way society discusses body weight. It started about 10 years ago with the body positivity movement, the idea that we should love our bodies at any size. But around that time, the American Medical Association also classified obesity as a disease. The medical community was divided, with some believing the classification would help reduce stigma while others argued that it pathologized larger bodies.

These transformational changes picked up speed with the arrival of powerful and wildly popular new medications that have already helped many people shed pounds.

We on the “Chasing Life” podcast team think it’s the perfect time to try to sort through some of these medical and cultural threads. That’s why we’re turning the spotlight on body weight in the coming season. For those listeners who, like me, really love the brain, there will be plenty here for you too, as the brain and body are forever linked.

We’re not going to reveal the secret to losing weight “with one weird trick” or even tell you that you should necessarily shed pounds. In fact, our very first episode explores the real link between weight and health. I spoke to Dr. Fatima Cody Stanford, an obesity medicine specialist at Massachusetts General Hospital and an associate professor at Harvard Medical School, about what our weight does and does not tell us about our health — and what she said might surprise you.

Beyond health care dollars

Despite changing attitudes about larger bodies, excess weight does carry a price.

From a health care standpoint, it costs the country a lot of money. According to a study published in the journal The Lancet in 2020, 27% of total health care expenditures in 2016 — about $730.4 billion — could be attributed to “modifiable risk factors” for preventable health conditions like cardiovascular disease. And high body mass index topped the list of those risk factors. It was responsible for nearly a third of that sum: $238.5 billion.

That was eight years ago, when our total health care expenditure was $2.7 trillion, according to the study. But health expenditures have only gotten larger: They grew by more than a trillion dollars between 2016 and 2022, when they hit $4.5 trillion, according to the National Health Expenditure Accounts. Without throwing even more numbers at you, I think we can safely say we are paying a lot of money for health care ultimately caused by excess weight.

But beyond the health care costs to society, there are real costs for individuals in terms of well-being, both physical and mental – and you can’t really put a price tag on that.

Almost 3 in 4 Americans 20 and older are classified as overweight or obese. But weight stigma is widespread, and our culture is steeped in blame and shame when it comes to weight.

It creates relentless pressure on hundreds of millions of people to slim down, exercise more and conform to certain beauty standards that are hard for many to approximate, let alone achieve on an enduring basis. They’re admonished to “get healthy,” which is often code for “lose weight.”

All the blood, sweat and tears do not even take into account the fact that the system we use to categorize people, body mass index, is flawed in the first place.

When Belgian mathematician, statistician and astronomer Adolphe Quetelet developed the formula (weight in kilograms divided by height in meters squared equals BMI) in the 1830s, he was trying to figure out, statistically speaking, the size of an “average man.” And by that I mean average European male in the 1830s.

The Quetelet formula was rebranded in 1972 as “body mass index” by physiologist Dr. Ancel Keys, who tried — and not without some controversy — to link body composition to health, disease and survival.

The formula, as Quetelet imagined it, was never meant to be used as a diagnosis. It was never meant to be applicable to other global populations. It does not take into account factors such as general health, muscle vs. bone vs. fat, gender, age subcutaneous vs. visceral fat or other considerations. And the categories (“underweight,” “normal,” “overweight” and “obese”) have arbitrary cutoffs.

“I can’t just judge the book by its cover and assume that someone [who] is larger is unhealthy and someone who is lean is healthy,” Stanford told me, referring to a person’s size and BMI. “That’s the assumption that people make. I call that practicing street-corner medicine.”

She said she looks beneath the surface of the individual to assess their health – for example, with bloodwork and their functional ability — “because someone who’s lean may be very unhealthy, and someone who’s heavier may be healthier.”

Has the cavalry arrived?

Stanford’s approach embodies a new way for doctors to think about weight. It parallels the body positivity movement and the body neutrality movement, appreciating your body for what it can do. These cultural shifts have appeared to be nudging us all toward becoming more accepting of larger bodies without having to change them, as long as they are physiologically and functionally healthy.

And then came a twist: the widespread adoption of a powerful and effective new class of medications originally developed to treat type 2 diabetes. Those drugs include semaglutide (sold as Ozempic, Rybelsus and Wegovy) and tirzepatide (sold as Mounjaro and Zepbound) as well as the older liraglutide (sold as Victoza and Saxenda). It’s hard to overestimate their impact on popular culture – and on the bodies of those who take them.

As of September, 1.7% of the US population was prescribed semaglutide for either diabetes or weight loss, and that figure is only expected to grow. A projection from JP Morgan analysts says that by 2030, 9% of the country’s population will be on these medications. That’s 30 million Americans. And drugmakers are hard at work synthesizing even more powerful medications.

These medications work by mimicking certain hormones our bodies release when we eat. When these hormones — or the drugs that mimic them – attach to receptors in our bodies, they are believed to do a number of things, including stimulating insulin production and signaling to our brains that we are satiated or full and can stop eating. One of the hormones, GLP-1, has also been shown to slow digestion so we feel fuller for longer.

For anyone who has ever tried to diet, that’s a pretty big deal, especially the parts about feeling full for longer and telling your brain that your body is done eating.

By many accounts, these new medications reduce “food noise” or “brain chatter,” intrusive thoughts about food, your next meal or that peach ice cream in the freezer. For many people, that food noise essentially creates the need for the constant exertion of willpower 24/7, an exhausting battle akin to walking around every day with a backpack full of rocks. (These drugs are so successful at quieting brain chatter that they’re being studied for other compulsive behaviors such as substance abuse, alcohol use disorder, smoking and gambling addiction.)

A coming change in the way we think about obesity

After covering medical news for more than two decades, I can say the introduction of these medications feels different. As with Prozac in the late 1980s and Viagra in the late 1990s, the arrival of these medications appears to be pivotal, maybe even revolutionary, because they work and seem to be safe, for the most part. That’s not to say some people don’t have unpleasant side effects and even, on occasion, very serious ones. Additionally, I should point out that when the drugs are stopped, the weight often returns, making these likely life-long drugs.

We are also in the middle of what I might call a paradigm shift in the way we think about the “disease” of obesity.

There’s a new idea, not fully formed with all the data yet, that there are different types of obesity. Soon, these different subtypes may be thought of as distinct diseases, much like how breast cancer is no longer considered one disease but many. These subtypes of obesity don’t all have the same underlying biology or cause, nor do they necessarily respond to the same types of treatment.

And that makes sense: We are not all built the same, and we have to take that into account. I know this from experience. My wife and I each wore a glucose monitor to track our blood sugar for a couple of weeks last year. Even though we both ate the same diet during that time, we found that certain foods caused our blood sugar to spike, and others did not – but it was different for each of us. I was sad to learn that one staple that spiked mine (but not Rebecca’s) is this Indian flatbread my mom makes; it’s a favorite of mine and my dad’s. (I shared this with my father, who has type 2 diabetes. He laughed and told me he already knew, because his glucose monitor had alerted him, as well!)

Success and shame

Even as we appear to be moving into a new phase of how we think about weight and weight loss in this country, thanks to changing attitudes and new medications, there’s still a fair amount of shame and stigma surrounding weight. They appear in two varieties.

The first form comes if you don’t use these new medications and remain in a larger-than-culturally-accepted body — and to be clear, many people cannot access or afford the medications, others can’t tolerate them, and some don’t lose as much weight as they hoped.

The second form of shame comes if you do use them, because few people are willing to talk openly about it. It is rare for a celebrity to be forthright about doing so. It’s akin to admitting that you lack the willpower to do this on your own or that you’re taking the easy way out.

We don’t place the same amount of shame on people who take medications for high cholesterol or high blood pressure. So why do we do this with weight loss medications, especially when most of us know from experience how hard it is to lose weight and keep it off?

(In episode 2 of this season, we’ll investigate the evolutionary forces at work when we speak to Harvard paleoanthropologist Dr. Daniel Lieberman, who’ll explain why our bodies are built to hold on to every last fat cell.)

That’s why, when Oprah came out and said she was on a medication to help her lose weight and keep it off, I was really impressed. She has always been ahead of the curve with respect to weight loss. Not only has she shared the literal ups and downs of the scale, she was honest enough in the first place to admit that she struggles with her weight – something very few people, prominent or otherwise, are willing to do.

So where is the inflection point? When will we start to see these medications as tools and not a sign of failure? And can we get to the point where we can be successful at weight loss – or accept ourselves the way we are — without shame?

I don’t have any easy answers for you, but these are just some of the themes we’re going to touch on and conversations we’re going to have during this season of “Chasing Life.” I hope you join us as we search for answers.

CNN’s Andrea Kane contributed to this report.

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