For years, longevity medicine has focused on two important goals: life span—how long we live—and healthspan—how long we remain healthy, active, and independent.

But there is a third dimension that deserves just as much attention:

Joyspan.

For example, in her book “Joyspan: The Art and Science of Thriving in Life’s Second Half,” gerontologist Dr. Kerry Burnight introduces a beautiful idea: living longer is not enough. Healthy aging is not enough. We should also think about how much joy, meaning, connection, and purpose we bring into those additional years.

Being Healthy Is Not the Whole Story

Today, we have remarkable tools to optimize health. We can monitor metabolic health, inflammation, hormones, sleep, cardiovascular risk, cognitive function, nutrition, exercise, and much more.

But imagine reaching 90 with excellent laboratory results while feeling lonely, disconnected, or without purpose.

Would we call that successful longevity?

I don’t think so.

The goal should not simply be to live longer, but to remain healthy enough to enjoy living.

Joy Is Part of Aging Well

Joyspan doesn’t mean being happy every day. Life inevitably brings stress, loss, illness, and change.

It means maintaining our ability to connect, learn, adapt, contribute, love, laugh, and look forward to tomorrow.

Perhaps we should think about longevity through three simple questions:

Lifespan: How long can I live?

Healthspan: How long can I remain healthy and independent?

Joyspan: How long can I remain engaged, connected, purposeful—and genuinely enjoy my life?

We spend a great deal of time measuring our health. But perhaps we should occasionally ask ourselves something much simpler:

Did I enjoy my life today?

How much did I laugh? Could I spend time with someone I love? What brand new thing did I learn? Has a beautiful object caught my eye? What am I looking forward to?

To me, this is what healthy aging should ultimately be about.

The goal is not simply to add years to our lives. It is to preserve the health that allows us to live those years—and the joy that makes those years worth living.

Lifespan. Healthspan. Joyspan.

Perhaps joyspan can remind us why we wanted more years in the first place.