Healthspan

The healthy-years gap widens as countries live longer

Across 185 countries, the distance between life expectancy and healthy life expectancy rises as life expectancy rises. Longer-lived populations gain healthy years in absolute terms while giving back a little of them in proportion.

SnapLongevity9 September 20264 min read

Healthy life expectancy is an attempt to measure this: not whether the years arrive, but whether they arrive with the capacity to use them.

Take every country in the WHO Global Health Estimates for 2021 and subtract healthy life expectancy from life expectancy at birth. The result ranges from 6.5 years in Somalia to 12.5 years in Australia — and across the 185 countries, the gap grows as life expectancy grows.

The relationship is strong: the correlation between life expectancy at birth and the size of the gap is 0.89. Among the 46 countries with the lowest life expectancy the mean gap is 8.0 years; among the 46 with the highest it is 11.1 years. This is a cross-country association within one year of data, not a finding about what happens inside a country over time.

Healthy life expectancy, or HALE, is life expectancy with time spent in illness or disability discounted according to how severe those states are estimated to be. It is a modelled accounting figure, not a count of people who were disease-free. How HALE is constructed.

Do longer-lived countries also have more healthy years?

Healthy life expectancy against life expectancy, at birth

WHO Global Health Estimates, life expectancy and healthy life expectancy (HALE) at birth, both sexes, 2021, all 185 countries in the dataset. The diagonal marks where the two values would be equal; no country reaches it.

Being precise about what the pattern is

Three separate statements are easy to confuse here, and only two of them are supported by these data.

Supported: across countries in 2021, the absolute gap in years is larger where life expectancy is higher (correlation 0.89, all 185 countries, no exclusions).
Supported: the share of life expected in full health varies within a narrow band — from 83.7% to 89.1% — and declines slightly as life expectancy rises (correlation -0.36).
Not supported by these data: that living longer causes more years of ill health, or that any individual country's gap will widen as it improves. A snapshot across countries cannot establish either.

The proportional finding is the one that keeps the absolute finding in perspective. A country at the top of the range still expects around 85% of its years in full health; a country at the bottom expects a similar share of a much shorter life. Australia, with the widest gap in the dataset, expects 70.6 healthy years — more healthy years in total than Somalia's entire life expectancy of 54.0.

6.5–12.5years
Range of the gap at birth: 83.7–89.1%
Share of life expected in full health: 0.89
Correlation of life expectancy with the gap

WHO Global Health Estimates, life expectancy and healthy life expectancy at birth, both sexes, 2021. Gap and share calculated from the unrounded published values.

The countries at each end

Swipe the table sideways to see all columns.

Widest and narrowest gaps between life expectancy and healthy life expectancy
Country	Life expectancy	Healthy	Gap	Healthy share
Australia	83.1	70.6	12.5	85.0%
United States of America	76.4	63.9	12.5	83.7%
New Zealand	82.2	70.0	12.2	85.1%
Switzerland	83.3	71.1	12.2	85.4%
France	81.9	70.1	11.8	85.5%
Somalia	54.0	47.4	6.5	87.9%
Lesotho	51.5	44.6	6.8	86.7%
Central African Republic	52.3	45.4	6.9	86.9%
Eswatini	54.6	47.5	7.1	86.9%
Guinea-Bissau	58.6	51.5	7.2	87.8%

WHO Global Health Estimates, at birth, both sexes, 2021, in years. The five widest gaps are listed first, then the five narrowest. Reading the narrow gaps as good news would be a mistake: they belong to countries with the shortest lives in the dataset.

That last point is the trap in this measure. A short life leaves less room for years lived in poor health, so countries with high mortality can show narrow gaps. The gap on its own is not a quality-of-life ranking, and no country would want to reduce its gap the way the bottom of this table did. Compare any country's two figures.

Why two countries with similar lifespans can differ in healthy years

Life expectancy is derived from age-specific mortality rates. HALE combines those same mortality rates with estimates of non-fatal health loss — musculoskeletal disorders, sensory loss, mental health conditions, diabetes complications. Two countries can bring mortality down to similar levels while carrying different burdens of conditions that reduce capacity without shortening life. The gap is where that difference shows up.

One mechanism is often proposed for the wider gaps in longer-lived countries: WHO's estimates place much of the world's non-fatal health loss at older ages, so a population in which more people reach those ages accumulates more of that time. The 2021 cross-country pattern is consistent with that account, but it is a snapshot of 185 countries and cannot on its own establish why the gap is wider where lives are longer.

Globally, healthy years have not kept pace with total years

WHO's own summary of the estimates makes the same point at global level: between 2000 and 2019 global life expectancy rose from 66.8 to 73.1 years while HALE rose from 58.1 to 63.5 — a gain of 6.4 years against 5.3. WHO attributes the HALE improvement primarily to declining mortality rather than to reduced years lived with disability. WHO also reports that by 2021 both figures had fallen back to their 2012 levels, at 71.4 and 61.9 years respectively, following the COVID-19 pandemic.