Just five healthy habits could add more than a decade to people's life expectancy, a new study has shown.

According to the findings, consuming a healthy diet, maintaining a healthy weight, exercising regularly, not smoking and drinking moderate amounts of alcohol could prolong a person's life expectancy at age 50 by 14 years for women and 12 years for men.

US researchers analysed data from two major ongoing studies, which saw men and women monitored for up to 34 years. They found that undertaking these five lifestyle behaviours significantly improved people's life expectancy.

Those who followed all five habits were 74% less likely to die during the follow-up period compared to those who did not follow any of them. They were 82% less likely to die from cancer and 65% less likely to die from heart disease.

Each habit reduced the risk of premature death on its own, however the combination of all five habits reduced this risk the most.

"Quantifying the association between healthy lifestyle factors and longer life expectancy is important, not only for individual behavioral changes, but also for health communicators and policy makers. It is critical to put prevention first.

"Prevention, through diet and lifestyle modifications, has enormous benefits in terms of reducing occurrence of chronic diseases, improving life expectancy as shown in this study, and reducing healthcare costs," commented the study's author, Dr Frank Hu, of the Harvard T.H. Chan School of Public Health in Boston.

Details of these findings are published in the journal, Circulation.