Researchers from University College London reported in JAMA Internal Medicine on the relationship between people’s perception of their own age and their actual life expectancy.

The study evaluated information from the English Longitudinal Study of Ageing, a database of 6,489 people who were followed for approximately eight years.

When entering the study, the volunteers were 54 or older. They were asked, “How old do you feel you are?”

On average, the volunteers were about 66 years old, but their average perceived age was 57.

Nearly 70 percent of the volunteers felt at least three years younger than their actual age, and only 5 percent felt more than a year older.

Those who perceived themselves as younger had a longer life expectancy; their mortality rate at the end of the study was only 14 percent, compared to the rate of 25 percent for those who perceived themselves as older.

Because the results could have been influenced by research volunteers who perceived themselves as older because of physical illness, the investigators repeated the analysis after excluding subjects who died after one year of follow-up.

They also controlled for heart disease, diabetes, cancer, smoking, drinking and other illnesses and behaviors that might increase mortality.

Secondary analyses confirmed the results: Feeling younger is associated with living longer.