Every Thursday after work, Dana drives forty minutes to her father’s apartment. She sorts his pills into a plastic weekly organizer, checks the refrigerator for spoiled food, and reads the mail he has stopped opening. He is seventy-eight. He has heart disease, early kidney trouble, and a memory that slips more each month. None of these problems arrived alone, and none of them will be solved alone. Dana sees three specialists’ names on his appointment card, and each one treats a different piece of the same slow process.
Dana has plenty of company. According to the Caregiving in the US 2025 report from AARP and the National Alliance for Caregiving, 63 million American adults provided ongoing care to someone with a medical condition or disability in the past year. That is almost one in four adults, and it is about 45 percent more than in 2015. Behind that number sits a simple fact that our health systems rarely say out loud: the main driver of most chronic disease in later life is aging itself.
This article makes one argument. Adding healthy years to human life is among the most valuable things a society can do, and it is worth treating as public policy rather than private luck. The evidence for that claim is strong in some places and thin in others, and both sides deserve an honest look.
The Gap Between Living Long and Living Well
Two numbers that tell different stories
The World Health Organization tracks two measures side by side. Life expectancy counts how many years a newborn can expect to live. Healthy life expectancy, which the WHO calls HALE, counts how many of those years are lived in full health. According to WHO data for 2021, global healthy life expectancy at birth was 61.9 years. Global life expectancy that same year was about 71.4 years. The difference, close to a decade, is the stretch of life most people spend managing illness or disability.
The same WHO table lists healthy life expectancy in the United States at 63.9 years in 2021, down 1.4 years from its 2000 level. A wealthy country with enormous medical spending has been losing healthy years. That gap is where Dana spends her Thursdays.
Why disease by disease is a slow road
Modern medicine is organized around single diseases. Cancer has its institutes, heart disease has its foundations, and dementia has its advocates. Yet the risk of nearly all of these conditions climbs steeply with age, and they tend to arrive together. Curing one often means a person lives long enough to meet the next.
Geroscience, the study of the biology of aging, takes a different approach. It asks whether slowing the shared underlying processes could delay many diseases at once. If that works even modestly, the effect would show up not as one conquered illness but as a later and shorter period of decline for millions of families.
What the Longevity Dividend Is Worth
The economists’ estimate
In 2021, economists Andrew Scott of London Business School and Martin Ellison of Oxford, together with Harvard geneticist David Sinclair, published “The economic value of targeting aging” in the journal Nature Aging. Using willingness to pay estimates drawn from existing data, they found that a slowdown in aging that raised American life expectancy by one year would be worth about 38 trillion dollars. A ten year gain would be worth about 367 trillion dollars. At a 2 percent interest rate, they calculated, the ten year gain equals about 7.2 trillion dollars a year, or roughly a third of 2019 United States GDP.
Two findings in that paper matter more than the headline totals. First, the authors concluded that compressing illness into a shorter span at the end of life is more valuable than simply adding years. Second, they showed that the value of improvement grows as we make progress, because each healthy year makes the next one more useful.
What the figures do and do not mean
These are not cash amounts sitting in a vault. They measure how much people would value extra healthy time, based on how they already trade money against risk. Still, the costs they reflect are real and familiar. Lost wages, forced early retirement, and nursing home bills all sit inside that estimate. For a household, the dividend looks less like a check and more like a parent who can still drive, cook, and live independently at eighty-five.
There is also an abundance argument here. A society where people stay healthy longer has more experienced workers, more active grandparents, more volunteers, and more time for each person to learn and contribute. Healthy longevity is one of the ways a future grows richer.
Working Models and Real Tests
The TAME trial and the problem of funding
The most famous test of the geroscience idea is the Targeting Aging with Metformin trial, known as TAME. According to the American Federation for Aging Research, it is designed as six year trials at 14 research institutions with more than 3,000 people aged 65 to 79. The goal is to learn whether metformin, a cheap diabetes drug used for more than sixty years, delays the onset of heart disease, cancer, and dementia together.
The trial’s story so far is instructive. Reporting on the effort notes an estimated cost of 45 to 70 million dollars, with the National Institute on Aging setting aside about 5 million. Because metformin is generic, no drug company stands to profit, so researchers have turned to philanthropists. AFAR’s own page still describes the work as raising funds to launch. A question that could affect hundreds of millions of people has waited years for an amount of money smaller than the budget of a single blockbuster film.
Aging as a target
TAME has a second purpose that may outlast its results. Regulators in the United States do not treat aging as a condition that a drug can be approved to address. The trial was designed partly to show that a composite outcome, such as time to the first of several age related diseases, can serve as a credible endpoint. If that model gains acceptance, it opens a path for many future treatments and for public funding to follow.
This is where policy matters. Markets reward patented products. They do not reliably reward cheap, open knowledge about which existing compounds, habits, or public health measures slow decline. Like open source software, that knowledge is a public good that no single buyer has enough reason to fund.
The Frank Counterarguments
Life expectancy gains have slowed
The strongest challenge comes from demography. In 2024, S. Jay Olshansky and colleagues published “Implausibility of radical life extension in humans in the twenty-first century” in Nature Aging. Studying the longest lived populations, including Japan, France, Switzerland, and South Korea, along with Hong Kong and the United States, from 1990 to 2019, they found that gains in life expectancy have decelerated. Their analysis suggests survival to age 100 is unlikely to exceed 15 percent for women and 5 percent for men this century. Old age mortality improved by an average of 30.2 percent over those three decades, and repeating that pace would add only about 2.5 years to life expectancy.
That is a serious cold shower for anyone promising near term immortality. Yet the authors themselves add an important condition. Radical extension is implausible, they write, unless the processes of biological aging can be markedly slowed. In other words, their work argues that the old toolkit of sanitation, vaccines, and disease by disease medicine has reached its limits. That is a case for testing the new approach, not a case against it.
Hype, inequality, and money
A second fair objection concerns hype. The longevity field attracts supplements with weak evidence, clinics selling unproven infusions, and confident claims built on mouse studies. Skeptics are right to demand randomized trials before anyone changes medical practice.
A third objection concerns fairness and cost. If therapies arrive as expensive patented products, the rich could gain healthy decades while others wait. Longer lives also strain pension systems built for shorter retirements. These problems are real, but they point toward design choices: public funding for trials of cheap compounds, open publication of results, and retirement rules that adjust to healthier lives. A future of abundance requires that the gains be shared, and that is a political choice as much as a scientific one.
What Readers Can Do Now
In your own household
Most of the healthy years available today come from ordinary, proven habits rather than exotic products. A few practical steps make a difference for individuals and caregivers alike.
- Talk with a doctor about the basics, such as blood pressure, physical activity, and sleep, before spending money on longevity supplements.
- Be wary of clinics and products that promise to reverse aging without published randomized trials behind them.
- If you are a caregiver, keep a single shared list of medications and appointments so that specialists see the whole person.
- Plan for longer lives by considering how work, savings, and housing might look across a retirement of twenty or thirty years.
As a citizen
Public policy follows public attention. Readers can ask elected representatives how much of the national medical research budget goes to the biology of aging compared with single diseases. They can support open, publicly funded trials of generic compounds, where the results belong to everyone. They can also push for caregiver support, since families will carry much of the load until science delivers more.
Sharing good information matters too. When a friend forwards a miracle cure, pointing them toward a trial registry or a peer reviewed study is a small act of care that slows the spread of false hope.
A Longer Season of Health
The real prize
The point of defeating aging was never to stretch out the hardest years. It is to shorten them and move them later, so that Dana’s father might have spent his seventies hiking, teaching a grandchild to fish, or simply reading his own mail. The economics say that prize is worth more than almost anything else we could buy. The demography says we will not reach it by doing more of the same.
A shared project
Seen clearly, healthy longevity is one of the most humane goals a civilization can set. It asks us to treat the time and vitality of every person as something precious and worth protecting. Science can supply the tools, but only a society that chooses to fund open research and share the results widely will turn those tools into a dividend for all.
This article is for informational purposes only and is not medical, financial, or legal advice. Please consult a qualified professional about your own situation.
