Vegetarians are less likely to develop ischemic heart disease than those who eat meat, British researchers found

Veggies Are Good for the Heart

Vegetarians are less likely to develop ischemic heart disease than those who eat meat, British researchers found.

In a prospective study, vegetarians in England and Scotland had a 32% lower risk of hospitalization or death from ischemic heart disease than nonvegetarians (HR 0.68, 95% CI 0.58 to 0.81), Francesca Crowe, PhD, of Oxford University, and colleagues reported online in the American Journal of Clinical Nutrition.

The difference was likely due to vegetarians’ lower levels of non-HDL cholesterol and lower systolic blood pressure, the researchers wrote.

Earlier prospective studies have shown that those who stick to a vegetarian diet are at reduced risk of death from heart disease, but few have looked at the combined outcomes of both fatal and nonfatal ischemic heart disease.

So Crowe and colleagues assessed data from the European Prospective Investigation into Cancer and Nutrition (EPIC) — Oxford study of 44,561 patients from England and Scotland.

Of those, 34% ate a vegetarian diet — defined as a diet that excluded meat and fish — at baseline, and the majority of vegetarians (76%) were women.

During an average follow-up of 11.6 years, there were 1,235 cases of ischemic heart disease, including 1,066 hospital admissions and 169 deaths.

Crowe and colleagues found vegetarians had a 32% lower risk of ischemic heart disease than nonvegetarians, which remained after adjusting for potential confounders including age, smoking, alcohol, physical activity, education, and contraceptive or hormone therapy (HR 0.68, 95% CI 0.58 to 0.81).

Further adjustment for BMI — which was lower in vegetarians at baseline — did lead to a small attenuation in risk, putting the reduction at 28% compared with nonvegetarians, but it was still significant.

And the advantages were seen whether patients had been vegetarians for a long time, or had only recently taken up the diet:

• Vegetarian for at least 5 years: HR 0.68, 95% CI 0.56 to 0.81
• Vegetarian less than 5 years: HR 0.70, 95% CI 0.52 to 0.95

Based on absolute rates of hospitalization or death, Crowe and colleagues calculated that the cumulative probability of ischemic heart disease between ages 50 and 70 was 6.8% for nonvegetarians compared with 4.6% for vegetarians.

The lower risk was probably mediated by differences in non-HDL cholesterol and systolic blood pressure, they noted.

“Vegetarians had a better lipid profile than did nonvegetarians, probably because of a higher ratio of polyunsaturated to saturated fat in their diet and a lower BMI,” they wrote.

The difference in non-HDL cholesterol concentrations between vegetarians and meat eaters was 0.45 mmol/L, which would predict a 16% lower risk of heart disease, based on data from other studies. And the 3.3 mm Hg lower systolic blood pressure would predict a 10% lower risk of the condition, the researchers estimated.

Those combined effects would predict a 24% lower risk of ischemic heart disease events in vegetarians, smaller than the 32% lower risk observed in the analysis, but within the 95% confidence interval, they wrote.

Source: http://www.medpagetoday.com/PrimaryCare/DietNutrition/37152