For decades, people living with excess weight have been told the same thing: "Eat less. Move more." If the weight didn't come off, the failure was framed as personal — a lack of willpower, discipline, or control.
That message was not only wrong. It was cruel.
Today, we are at a turning point in cardiovascular medicine. Evidence from new therapies and trials points to a disruptive hypothesis: dysfunctional fat — and the signals it releases — may be central to heart and metabolic disease. If this proves true, recognizing and treating fat biology could be as foundational as treating cholesterol or high blood pressure.
This possibility demands urgency: clearer conversations with patients, routine consideration of pharmacologic obesity treatment, and a scientific agenda that rigorously tests whether changing fat biology can prevent or reverse disease.
Fat as an Organ
We don't hesitate to talk about the liver, the spleen, or the kidneys. We shouldn't flinch at calling fat an organ, too.
Scientists now recognize fat as a living organ that communicates through hormones called adipokines (say it slowly: ADD-ih-po-kines). Think of them as text messages fat sends to the rest of the body.
In healthy fat, adipokines are protective: they calm inflammation, prevent scarring in the heart and kidneys, and help the body balance salt and water.
As fat expands — especially the deep, hidden fat wrapped around our organs, known as visceral fat — this balance shifts. Even people who don't look heavy on the outside can carry dangerous amounts inside.
The protective signals are suppressed. Harmful ones take over.
Milton Packer, a leading heart failure scientist, has suggested that we can think about adipokines in three domains:
Domain I (Protective): the guardians, nurturing the heart and kidneys, fighting inflammation.
Domain II (Compensatory): the helpers, rising in obesity as the body tries to adapt — but never enough to fully restore balance.
Domain III (Harmful): the saboteurs, promoting scarring, fluid retention, and inflammation.
When the saboteurs drown out the guardians, disease takes root.
A Heart That Stiffens, Not Weakens
When visceral fat drives this shift in adipokine signaling, the result is heart failure with preserved ejection fraction (HFpEF).
Think of Margaret, a 68-year-old teacher. She used to climb three flights of stairs to her classroom. Now she's breathless by the second floor, too tired to keep up with her grandchildren at the park.
Her heart tests puzzle her doctors:
The heart still pumps normally (its "ejection fraction" is preserved).
But it has become thickened, stiff, and less adaptable.
She feels exhausted, short of breath, unable to do the things she once could.
Margaret's story is increasingly common. HFpEF is now the most common form of heart failure in the U.S., affecting an estimated 4 million people. More than 90% of patients with HFpEF have central adiposity — excess fat around the waist, which usually signals fat packed around the organs inside.
Traditionally, high blood pressure was thought to be the main cause. But the timing tells a different story: the rise of HFpEF has tracked closely with the epidemic of obesity. The adipokine hypothesis suggests that Margaret's hidden visceral fat may have been sending toxic signals to her heart for years, gradually making it stiffer and less responsive.
Reframing Obesity
This new science reframes obesity itself. It is not about weakness. It is not about failure. It is about biology.
For years, medicine relied on body mass index (BMI) — a blunt measure that doesn't tell us where fat sits in the body. BMI is like a bathroom scale with blinders on: it tells you how heavy you are, but nothing about where the fat is.
What matters most is distribution. A simple waist-to-height ratio — if your waist is bigger than half your height — is a much better predictor of risk. Even people with a "normal" BMI can have dangerous visceral fat if their waist-to-height ratio is high.
Visceral fat isn't just "extra weight." It is an active organ, releasing harmful signals that stiffen your heart, raise your blood pressure, and inflame your blood vessels. Understanding this changes everything about how we approach treatment.
The Human Cost of Blame
For generations, people have carried not only the physical burden of excess weight but also the psychological burden. Shame. Guilt. The sense that if only they tried harder, they could fix it.
This new understanding should release us from that burden. If fat is an organ that sends toxic signals, then living with adiposity is not a character flaw. It is a medical condition — one we can now study, understand, and treat.
Lifestyle still matters — eating well and moving regularly remain cornerstones of health. But we must stop pretending that biology can be overcome by advice alone.
The Dawn of New Therapies
This isn't just conceptual. We already have evidence that treating obesity can improve heart failure outcomes, and emerging research suggests these treatments may be reshaping fat biology in the process.
GLP-1 receptor agonists (like semaglutide and tirzepatide) not only cause weight loss, but they specifically reduce visceral fat and may help restore healthier adipokine signaling.
SGLT2 inhibitors, mineralocorticoid receptor antagonists, and angiotensin receptor–neprilysin inhibitorsmay partly work by dialing down harmful adipokines and boosting protective ones.
Early evidence shows that treating obesity can improve heart failure outcomes. Whether this works through the adipokine pathway, or other mechanisms, is still being studied. But the clinical results offer genuine hope and suggest we're on the right track.
A Turning Point
Medicine has had moments like this before. We didn't always know cholesterol mattered. We didn't always know blood pressure was a silent killer. Today, fat biology may be the next frontier.
If dysfunctional fat is not a bystander but a driver, then treating it may be as foundational as treating cholesterol or hypertension.
From Blame to Biology, From Advice to Action
This is the real turning point: shifting from a culture of blame to one of biology — not just for patients, but for all of us.
For people living with excess weight, this science offers relief from stigma and hope grounded in evidence. Your struggle was never simply about willpower. It was about biology.
For the rest of us, it's a wake-up call about how we think about and treat those individuals. The person struggling with weight isn't lacking discipline — they may be dealing with an organ system that's sending harmful signals throughout their body.
For the medical profession, it's an entire mindset shift. We're not treating how people look. We're treating cardiovascular health, metabolic dysfunction, and potentially much more. This means moving beyond appearance-based judgments to biology-based interventions.
And biology we can change. That is the turning point.
"For generations, people have carried not only the physical burden of excess weight but also the psychological burden. Shame. Guilt. The sense that if only they tried harder, they could fix it."
In this conversation, people tend to be weirdly sensitive and thin skinned about any suggestion that they are being criticized or judged for their weight, and sensitive about the indisputable fact that extra weight is bad for your health, or that someone, somewhere might find being overweight unattractive.
Two things can be true:
1. If you "eat less and move more" (opinions vary on which of those two things is more important), you'll lose weight. (I have personally done this, so please don't bother telling me "it's impossible", I don't think I'm some weird physiological outlier and my lived experience is more persuasive to me than your words).
2. it is not *easy* to "eat less and move more". It isn't! (again, I did this and I know what was involved). It takes months at a minimum, It involves changing habits, changing how you live, saying no to family and cultural expectations about what you will eat and when, finding ways to habitually move more and integrating that into your life, in a society and built environment that does not always support this. All this takes time, and sometimes it takes money, and it takes mental bandwidth, and people don't always have a surplus of those things. But yes, it does also take willpower and belief. Being told the falsehood that "it can't be done", or that the problem is not the weight, but societies' perception of the weight, certainly doesn't help.
Well said & long overdue from (us in) healthcare: 'For decades, people living with excess weight have been told the same thing: "Eat less. Move more." If the weight didn't come off, the failure was framed as personal — a lack of willpower, discipline, or control.
That message was not only wrong. It was cruel.' Thank you!