About 600,00 people die every year from heart disease in the United States; that’s one in every four deaths. It is the leading cause of death for both men and women. To what do we owe this epidemic?

New research from University of Oxford may provide some clues. A study of 44,500 people in England and Scotland revealed that vegetarians were 32 percent less likely to die or to need hospital treatment as a result of heart disease.

The scientists looked at data from 15,100 vegetarians and 29,400 people who ate meat and fish. During the course of the 11-year study, 169 participants died from heart disease and 1,066 required hospital treatment —and those individuals were more likely to have been meat and fish eaters than vegetarians.

Differences in cholesterol levels, blood pressure and body weight are thought to be behind the numbers.

“Most of the difference in risk is probably caused by effects on cholesterol and blood pressure,” said Dr. Francesca Crowe, lead author of the study at the Cancer Epidemiology Unit, University of Oxford. “Vegetarians probably have a lower intake of saturated fat, so it makes senses there is a lower risk of heart disease."

The Oxford team calculated the risk reduction at 32 percent after accounting for other factors such as age, smoking, alcohol intake, physical activity, educational level and socioeconomic background. Crowe said, "The main message is that diet is an important determinant of heart health.”

And although the number is sobering, if you’re an omnivore not ready to give up the whole hog, adopting some moderation still might help.

Dr. Kevin Marzo, chief of cardiology at Winthrop-University Hospital, in Mineola, N.Y., noted, "Though not addressed in this important study, for those not ready for a meat-free diet, pesco-vegetarians (fish) and semi-vegetarians who limit animal products but still eat meat once or week or so, may have 'intermediate protection' against heart disease."

The findings were published in the American Journal of Clinical Nutrition.

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