A vegetarian diet may be the key to living a longer and healthier life, with men reaping the most benefits, according to new research.

Vegetarian diets were associated with reduced death rates in a study of more than 70,000 Seventh-day Adventists with more favourable results for men than women, researchers said.

The possible relationship between diet and mortality is an important area of study.

Vegetarian diets have been associated with reductions in risk for several chronic diseases, including hypertension, metabolic syndrome, diabetes mellitus and ischemic heart disease (IHD), according to the study. Michael J Orlich, of Loma Linda University in California, and colleagues examined all-cause and cause-specific mortality in a group of 73,308 men and women Seventh-day Adventists.

Researchers assessed dietary patients using a questionnaire that categorised study participants into five groups: non vegetarian, semi-vegetarian, pesco-vegetarian (includes seafood), lacto-ovo-vegetarian (includes dairy and egg products) and vegan (excludes all animal products).

The study noted that vegetarian groups tended to be older, more highly educated and more likely to be married, to drink less alcohol, to smoke less, to exercise more and to be thinner. "Some evidence suggests vegetarian dietary patterns may be associated with reduced mortality, but the relationship is not well established," the study noted.

There were 2,570 deaths among the study participants during a mean (average) follow-up time of almost six years. The overall mortality rate was six deaths per 1,000 person years, according to the study published by JAMA Internal Medicine.

The adjusted hazard ratio (HR) for all-cause mortality in all vegetarians combined vs non-vegetarians was 0.88, or 12 per cent lower, according to the study results. The association also appears to be better for men with significant reduction in cardiovascular disease mortality and IHD death in vegetarians vs non-vegetarians.

In women, there were no significant reductions in these categories of mortality, the results indicate. "These results demonstrate an overall association of vegetarian dietary patterns with lower mortality compared withthe non-vegetarian dietary pattern. They also demonstrate some associations with lower mortality of the pesco-vegetarian, vegan and lacto-ovo-vegetarian diets specifically compared with the non-vegetarian diet," the authors concluded.