Long Life, Short Death — or Long Decline?

This article explains research for general understanding. It is not medical advice, and nothing here is a recommendation about any treatment or health practice. The figures discussed are population estimates, and findings can change as research develops. If you have a health question, talk to a qualified professional who knows your circumstances.

Two women died in the same week. Both were eighty-one.

The first had been unwell for a long time. She stopped driving at seventy. By seventy-four, stairs had become difficult. Later came the walking frame, then the chair by the window. She lived with illness for eleven years.

The second was working in her garden until eleven weeks before the end. Then something went wrong, and it did not go right again.

On a chart that records life expectancy, these two lives are identical. Both lasted eighty-one years.

Which raises a simple question: if the number says they lived the same length of time, what exactly is it measuring?

Before going further, one thing should be said plainly. Nothing here is a judgement on the first woman’s eleven years. They were her life. A statistic that counts them the same as anyone else’s is not weighing them — it is a national accounting tool, and it cannot see any individual at all. That distinction matters, because everything that follows is about the tool.

Life expectancy is one of the most quoted numbers in the world. It tells us how long people live, on average. What it does not tell us is how healthy those years are. A year spent hiking through mountains and a year spent confined to a hospital bed both count exactly the same. Life expectancy was designed to measure survival, and it does that very well. It was never designed to measure wellbeing.

So researchers built a second measure: healthy life expectancy — often shortened to HALE, for health-adjusted life expectancy. Instead of asking “How long do people live?”, it asks “How many of those years are lived in reasonably good health?” The difference between the two numbers is commonly used as an estimate of the years, on average, spent living in less-than-good health. Researchers call that difference the morbidity gap.

A simple example makes this easier to see. Imagine a country where people live to 80 and stay healthy until 72. The gap is 8 years. Twenty years later, people there live to 85 but stay healthy only until 74. Life expectancy has risen by 5 years; healthy life expectancy by only 2. The gap has grown from 8 years to 11.

That is not just a hypothetical. Between 1990 and 2023, global life expectancy at birth rose from about 64.6 years to about 73.8. Healthy life expectancy rose too, but more slowly — from about 55.9 to about 63.1. Both improved. Survival improved faster. The gap widened. In plain terms, we are adding years to life faster than we are adding life to years.

Many people assume there must be a trade-off — that we face two options. Live a long life and spend many years declining. Or live a shorter life but stay healthy until near the end. The data suggests it does not divide so neatly.

A study of 183 countries, using World Health Organization estimates for 2019, found the widest gap of all in the United States, at about 12.4 years. Australia, New Zealand, the United Kingdom and Norway followed close behind. The narrowest gaps were in Lesotho, at about 6.5 years, then the Central African Republic and Somalia (Garmany and Terzic, 2024).

That list reads backwards unless you are careful. A narrow gap is not good news. Lesotho does not enjoy a short and gentle ending; it has a shorter life overall, and the unwell stretch is fewer years simply because there are fewer years in total. The wider pattern holds across development levels: the more developed a country, the wider its morbidity gap tends to be. In the 2023 global figures, the gap was widest in the most developed group of countries and narrowest in the least developed (Global Burden of Disease Study 2023). So far, longer lives have mostly arrived together with more years spent unwell.

But “mostly” is doing real work in that sentence, and researchers have argued about it for nearly fifty years.

In 1977 an American psychiatrist, Ernest Gruenberg, published a paper called “The failures of success.” His argument was that medicine’s victories carried a hidden cost: diseases that once killed quickly were becoming diseases people lived with, sometimes for decades. Three years later James Fries, a physician at Stanford, argued the opposite in the New England Journal of Medicine. If illness could be delayed faster than death, the unwell stretch at the end would be squeezed shorter — a long life followed by a short decline. In 1982 the demographer Kenneth Manton offered a third possibility: people might live longer with chronic conditions that were more common but less severe, caught earlier and better managed.

So the apparent pattern — longer life, longer decline — is only the average. The evidence today suggests all three outcomes can occur, and that different diseases and different populations produce different results. There is no single universal law here, which is exactly why the field is still arguing.

One consistent finding sits inside all of it. In almost every country, women live longer than men — yet they also spend more of those extra years living with illness or disability. In 2023 the gap averaged about 12.1 years for women and about 9.3 years for men (Global Burden of Disease Study 2023).

A necessary caution about all these figures: they are estimates, not direct measurements. Healthy life expectancy is modelled, not counted. It is built from disease estimates, from surveys in which people report their own health, and from disability weights — numbers that say how much each condition subtracts from a healthy year. Reasonable people disagree about those weights. Definitions shift. Diagnoses shift. And no population average describes any single person.

It is also worth being careful about what a widening gap actually shows. It could mean more people are surviving illnesses that once killed them quickly, and living on with those illnesses. It could mean the line for calling someone ill has moved, so more people are counted as unwell without anything having changed in their bodies. It could simply mean populations are older, and more years lived means more years in the stretch of life where illness gathers. These are not the same thing, and the numbers alone cannot separate them.

Deaths are easy to count. Years are easy to count. Health, independence, and vitality are much harder. So we lean on the numbers we have.

And those numbers describe a real achievement. Life expectancy is one of the great success stories of modern life, and rightly so — millions of people are alive today because medicine, sanitation, nutrition, and public health improved dramatically over the last century. We have become very good at adding years to life. The harder measurement problem is what happens inside those years.

Which brings us back to the two women. The chart sees two eighty-one-year lives as identical. Most people do not. One number tells us how long a life lasted; the other tries to tell us how much of it was spent in good health. Neither captures a whole human life. No number ever will.

In short: as people live longer, the years lived in poor health have grown too, and that gap is widest in the most developed countries — but whether long life must come with a long decline is genuinely unsettled, and the statistics themselves cannot yet tell us why the gap is widening.

What follows is my own reading, not a finding in the research: the studies measure the gap, but they do not tell us what it should mean to us. So perhaps the more useful question is not how many more years we can add — but how we want to live in the ones we already have.

 

Glossary

Life expectancy — the average number of years a person is expected to live, usually measured from birth. It counts length of life only, not its quality.

Healthy life expectancy (HALE) — short for health-adjusted life expectancy: the average number of years lived in reasonably good health. Unlike life expectancy, it is modelled from health data rather than directly counted.

Morbidity gap — the difference between life expectancy and healthy life expectancy: an estimate of the years, on average, spent living in less-than-good health.

Chronic condition — a long-lasting illness, such as heart disease or arthritis, that is generally managed over time rather than cured.

Disability weight — a number used in building HALE that represents how much a given health condition subtracts from a year of full health.

Sources

Gruenberg, E. M. “The failures of success.” Milbank Memorial Fund Quarterly: Health and Society, 1977, 55(1), 3–24.

Fries, J. F. “Aging, natural death, and the compression of morbidity.” New England Journal of Medicine, 1980, 303, 130–135.

Manton, K. G. “Changing concepts of morbidity and mortality in the elderly population.” Milbank Memorial Fund Quarterly: Health and Society, 1982, 60(2), 183–244.

Garmany, A., and Terzic, A. “Global Healthspan-Lifespan Gaps Among 183 World Health Organization Member States.” JAMA Network Open, 2024, 7(12), e2450241.

Hay, S. I., et al. “Global, regional, and national trends in the morbidity gap and contributing diseases, injuries, and risk factors, 1990–2023: a systematic analysis for the Global Burden of Disease Study 2023.” The Lancet Public Health, 2026.