Staying in school longer may slow how fast your body ages, according to a new analysis of data from more than 3,000 people across three generations.

Researchers from the United States, Norway and the United Kingdom used an epigenetic clock, which measures biological age through markers in DNA, on data from the Framingham Heart Study. They found that two extra years of schooling equated to 2 to 3 percent slower aging on average.

The finding builds on earlier work showing each additional year of education cuts mortality risk by about 2 percent, according to a major study published in The Lancet Public Health drawing on data from 59 countries.

Scientists stress the effect works through many channels: better jobs and income, better access to healthcare, healthier habits and stronger social resources.

The message is simple and hopeful. Education is not just about qualifications. It may literally add healthy years to your life.