Scientists have produced powerful evidence that a Mediterranean diet rich in vegetables and fruit and low in saturated fats can help us live longer.
Vegetables are a key part of a healthy diet
It has long been thought that the diet can help to improve general health.
But a major pan-Europe study of 74,607 men and women aged over 60 has shown closely following the diet can actually extend life by up to one year.
The study, led by University of Athens Medical School, is published in the British Medical Journal.
The researchers collected information on areas including diet, lifestyle, medical history, smoking and physical activity.
High intake of vegetables, fruits and cereals
Moderate to high intake of fish
Low intake of saturated fats
High intake of unsaturated fats, such as olive oil
Low intake of dairy products and meat
Modest intake of alcohol, mostly wine
The men and women were each given a score based on adherence to a Mediterranean diet, with higher scores for those who ate the most foods linked to such a diet.
The researchers found that overall a higher dietary score was linked to a lower overall death rate.
They said that a two-point increase in the score was linked to an 8% reduction in mortality.
A three-point increase was associated with an 11% drop in mortality and a four-point increase was associated with a 14% drop.
This meant that a healthy man of 60 who stuck closely to a Mediterranean diet could expect to live around one year longer than a man of the same age who did not eat such a diet.
The researchers said the link was strongest in Greece and Spain - probably because people in these countries followed a genuinely Mediterranean diet.
UK lagging behind
Rebecca Foster, a nutrition scientist at the British Nutrition Foundation, said diets in the UK were not as healthy as those followed by many of their European counterparts.
"Although dietary surveys indicate that we are eating fewer calories, less total fat and we are beginning to see a reduction in salt intake, we are still not meeting the UK dietary guidelines, which are in line with the characteristics of the Mediterranean diet.
"In particular, the Mediterranean countries such as Spain and Greece eat a lot more fruit and vegetables and have a lower intake of saturated fat."
However, she said the study findings could in part be down to genetic factors, rather than simply diet alone.
Belinda Linden, of the British Heart Foundation, said: "Dietary studies are often difficult to carry out as it is hard to define which constituent of the diet provides the most benefit.
"But that should not put us off trying - it is vital that large and in-depth dietary studies such as these are carried out to further our understanding of the way different diets affect our health.
"This study adds detailed evidence to previous findings and confirms that this type of diet, containing all the essential components of the Mediterranean diet, can be linked with prolonged life.
"Importantly, however, the diet is only one part of lifestyle change needed to reduce coronary heart disease and we must also aim to increase our activity levels, control our weight and stop smoking."