Have you got the body of someone 10 years younger?

Keeping active is key for a long, healthy life. Photo / Thinkstock

A healthy lifestyle at 75 gives a person the same chance of living for a further 10 years as someone a decade younger who smokes and drinks, a study has found.

For the first time, researchers have calculated a pensioner's chances of surviving for another decade, based on habits such as smoking, drinking, exercise and fruit consumption.

The study of more than 16,000 people found that men aged 75 who smoked, regularly drank alcohol, led inactive lifestyles and ate little fruit had just a 35 per cent chance of being alive a decade later.

Others of the same age who did not smoke, did exercise, ate fruit and had moderate or no alcohol consumption had a 67 per cent chance of living a decade - the same figure for men 10 years younger with unhealthy lifestyles.

Among women, 75-year-olds with healthy lifestyles had a 74 per cent chance of being alive a decade later. The projection was only slightly lower for women 10 years' younger who smoked, drank a lot, rarely ate fruit and took little exercise.

The calculator, from a team at the University of Zurich, allows men and women aged 65 and 75 to estimate their chances of living for a decade.

Alcohol intake was classed as high if women reported drinking at least two units of alcohol a day (175ml wine) and if men drank at least four units (less than two handles of beer) a day. The study found that lifestyles had little impact on death rates among those aged between 45 and 55, but had major consequences from the age of 65 onwards.

Smoking had the greatest impact on life expectancy, increasing the risk of premature death by 57 per cent.

Each of the other three factors - alcohol, diet and exercise - increased risk by around 15 per cent each.

Eva Martin-Diener, the study's lead author at Zurich's Institute of Social and Preventive Medicine, said: "The effect of each individual factor on life expectancy is relatively high.

"A healthy lifestyle can help you stay 10 years' younger."

Women aged 65 with the healthiest lifestyles had a 90 per cent chance of living a decade, compared with a 77 per cent chance for those with unhealthy habits.

The chance of a man aged 65 living a decade ranged from 67 per cent to 86 per cent, depending on their habits, the research found.