Healthspan versus lifespan — why the right target is to compress morbidity

João is 78. He came to the visit accompanied by his daughter — and the conversation that followed was one I have rarely shaken off.

Walk that back: He is 78. He came to the visit with his daughter. He has walked with a cane since 71. He has had diabetes since 64, a heart attack at 68, atrial fibrillation at 72, a hip replacement at 74, a fall and a femur fracture at 76. He takes eleven pills a day. Doctor, I lived a long life, he told me. But I haven't lived well in ten years.

The daughter, who is 50, listened in silence. She was trying to understand whether her father's path is her own. And she came with the right question, the one I wish more patients would ask me: it isn't how long I will live. It's how many of those years I will live well.

That is the distinction that organizes 21st-century longevity medicine. Lifespan is how long you live. Healthspan is how long you live well — without disabling disease, without significant chronic pain, without the loss of function that takes away what defines being an autonomous person. And the gap between the two numbers, almost everywhere in the world, is widening.

The intuition James Fries had in 1980

The concept is not new. In July 1980, in the New England Journal of Medicine, James Fries published a six-page paper that quietly changed how I, and a generation of researchers, think about aging. The title: "Aging, Natural Death, and the Compression of Morbidity."

Fries observed a simple fact: average life expectancy rose dramatically across the 20th century — from 47 to more than 73 years — but the maximum limit of human life barely moved. Survival curves were becoming more "rectangular" — almost everyone reaches a similar age and dies within a narrower interval. The logical consequence, and his proposal: if the ceiling does not rise, the reasonable goal is not to extend the end, but to postpone the onset of morbidity — pushing the start of disease and disability closer to the end. Compress the period of decline. Live well for longer, and die quickly.

Forty-six years later, I can say that proposal is technically possible — I have seen populations and individuals who did compress morbidity — but in practice, in the wards I trained in and the offices I have run, the expansion of morbidity has won. People are living longer, yes. But they are living more years sick.

The number no one looks at — the healthspan-lifespan gap

The broadest analysis I have read was published in December 2024, in JAMA Network Open, by Garmany and Terzic. They compared life expectancy (lifespan) with healthy life expectancy (healthspan, measured by the WHO HALE metric) across 183 countries from 2000 to 2019.

The findings are uncomfortable. The global average gap between the two numbers grew from 8.5 to 9.6 years over the period. Almost a decade lived in disease or significant disability. And the worst position among developed economies was the United States, with a 12.4-year gap. Women had, on average, 2.4 more years of gap than men — not because they live worse, but because they live longer through the phase in which non-communicable diseases (cardiovascular, metabolic, oncologic, neurodegenerative) collect their bill.

Brazil sits in an intermediate position, but with the same trajectory — gap widening, strongly correlated with the rise of the same chronic diseases. This is not destiny. It is the pattern of metabolic, dietary, sleep, and stress exposure accumulated over decades.

On the ceiling and the importance of changing the goal

In October 2024, in Nature Aging, Olshansky and colleagues published a study that offered the complementary argument. Examining the world's longest-lived countries (Japan, Sweden, France, Italy, South Korea, Hong Kong, and others) between 1990 and 2019, they showed that gains in life expectancy are decelerating. Survival curves are approaching a biological ceiling. The probability of a woman reaching 100 years old, even in the longest-lived countries, will likely not exceed 15% — and for men, 5% — without some radical intervention in the biology of aging that does not yet exist.

My practical reading, after seeing thousands of patients over the years, is direct: spending energy trying to live to 110 is, for the vast majority of us, an illusion. Spending energy trying to reach 85 with cognitive function preserved, full mobility, autonomy, sexuality, and pleasure — that is different math. It is realistic, it is measurable, it is modifiable.

The Garmany, Yamada, and Terzic review in npj Regenerative Medicine (2021) had already put it in a single phrase: "longevity leap — mind the healthspan gap." The longevity leap already happened in the last century. The next chapter is closing the gap between being alive and being well.

What compresses morbidity — there is no mystery

The literature is monotonously consistent about which factors separate those who reach 80 functional from those who reach 80 dragging:

Aerobic capacity and strength. A VO₂ max in the top quartile is associated with 4 to 5 times less mortality than the bottom quartile, in studies of more than 100,000 people. Hand grip strength predicts mortality better than blood pressure does. I tell my patients every week: muscle is the organ of functional longevity.

Body composition. Preserved lean mass and low visceral fat. BMI matters less than the relationship between the two. Silent sarcopenia begins at 30, accelerates at 60, and is the principal substrate of the frailty that strips autonomy.

Metabolic health. Preserved insulin sensitivity. ApoB and Lp(a) under control. HbA1c below 5.7%. Blood pressure well controlled early. These numbers, maintained through the decades of one's 30s, 40s, and 50s, define the vascular state of one's 70s.

Sleep. Seven to nine regular hours, with preserved architecture (REM and slow-wave), across decades. Sleep is when the brain's glymphatic system clears beta-amyloid. Chronic deprivation is a risk factor for Alzheimer's comparable to hypertension.

Social connection. The literature on loneliness as a cardiovascular and cognitive risk factor is as solid as any classical biomarker I have ever measured. Social isolation has an effect comparable to smoking 15 cigarettes a day.

Purpose. Studies of centenarians in Japan, Sardinia, and Costa Rica converge on a banal and profound finding: people who live well for a long time have a reason to get up in the morning. Ikigai, in Japanese.

None of these factors are secret. None are expensive. What is missing, almost always, is someone looking at all of them together, on the same day, for the same person.

The medicine that pursues lifespan vs. the one that pursues healthspan

When I coordinated the residency at Santa Casa, I learned how Brazilian assistance medicine was built — to treat established disease. It is excellent at acute heart attacks, sepsis, and diagnosed cancer. It does less well at stratifying 20-year risk, planning a function trajectory, optimizing physiologic reserve before it is needed. It is not incompetence — it is design. The system measures consultations, labs, hospitalizations. It does not measure healthy years added.

Compressing morbidity requires a different model. It requires measuring what matters before it hurts. It requires following trend, not snapshot. It requires a team — because healthspan is built in the friction between nutrition, strength, sleep, emotional regulation, metabolic, hormonal, and vascular control. None of those, in isolation, holds the curve.

The reading I make in the office

In my consultations, I treat the longevity score — over 800 items spanning history, symptoms, labs, and habits — as a way to operationalize the concept of healthspan: you are not "healthy" or "sick." You are at some position on the trajectory, and I can measure that position, follow it, and help you modify it. Reviewing the whole picture every three to six months is not organizational luxury. It is the only way I have found to read the entire trajectory rather than fragments of it.

João's daughter, who came to the visit, is 50. ApoB 124. Fasting insulin 13. Fragmented sleep, walks for exercise three times a week, no strength training. Waist 92 cm. She has, at this moment, more or less the markers her father had at 50. The difference is that I am looking at them at 50, not at 68.

The years that separate living long from living well are not destiny. They are the consequence of what is done in the three preceding decades. Compressing morbidity is a project. It begins early, demands consistency, and can be measured along the way. The other path — João's path — is also a project. Only it is the project of inaction.