Healthspan: adding life to your years

Two different numbers.

Lifespan is how long we live. Healthspan is how long we live in good health. For most of the last century, public health measured success by the first number. Today the second one deserves just as much attention.

Researchers at Mayo Clinic compared the two across 183 countries using World Health Organization data. Worldwide, the gap between them grew from 8.5 years in 2000 to 9.6 years in 2019. The United States had the widest gap of any country studied: about 12.4 years, on average, lived in less-than-good health. For American women, it was 13.7 years.¹

Why the gap keeps growing.

The lost years are mostly years lived with chronic disease. Countries with larger gaps carried a heavier burden of conditions like heart disease, diabetes and lung disease.

In 1980, the physician James Fries hoped we would “compress” illness into a short stretch at the very end of life. Decades later, his own review concluded that this is “clearly not inevitable”.² In the US, the years older adults spend living with disease actually rose between 1998 and 2006.³ Populations are not closing the gap on their own. Individuals, it seems, have to do it on purpose.

The United States had the widest gap of any country studied: about 12.4 years, on average, lived in less-than-good health.

What tends to go with more healthy years.

The most useful evidence comes from large studies that follow people for many years. In one analysis of 116,043 adults across 12 European cohorts, people with the healthiest combination of four habits (not smoking, staying active, keeping a healthy weight and drinking little or no alcohol) lived about 9 to 10 more years free of diabetes, heart disease, stroke, cancer and chronic lung disease than people with the least healthy combination.⁴

Each piece has its own story. Daily steps: the lowest risk of death was seen at about 6,000 to 8,000 steps a day for adults over 60, and 8,000 to 10,000 for younger adults.⁵ Smoking: smokers lost more than 10 years of life on average, and quitting between 45 and 54 won back about 6.⁶ Sleep: both very short and very long sleep were linked to higher mortality, with six to eight hours a night looking most favourable.⁷ Connection: people with stronger relationships had about 50% greater odds of survival across 148 studies.⁸

Alcohol is the one to read carefully. Older studies often counted moderate drinking as healthy, but analyses that correct how former drinkers were classified have not found a protective effect.⁹ The safest reading today is simple: less is better.

It is not too late.

This is the part of the research we find most hopeful. In a study of 14,599 adults aged 40 to 79, people who became more active over time had lower mortality than people who stayed the same, about 24% lower for each step up, roughly the difference between being inactive and meeting basic activity guidelines. The link held whatever their past activity level, and even among people already living with heart disease or cancer.¹⁰ Quitting smoking in midlife tells the same story.

A practice, not a prescription.

None of these habits is dramatic. They are ordinary things done often: moving most days, protecting sleep, staying close to people, noticing what your body is telling you. That is the heart of our tagline, Forever is a practice. Healthy years are not bought in a single weekend. They are built in the quiet, repeated choices that make up a normal week.

How to read these numbers.

Almost all of this research is observational. It shows that people who live a certain way tend to fare better, not that any one habit will add a set number of years for any one person. People who keep one healthy habit often keep others, which can make each habit look more powerful than it is.¹¹ That is why we write “linked to” and “associated with,” and why we never promise outcomes. The direction of the evidence, though, is consistent and encouraging.