Impact of Vegetarian Diet on Heart Disease, Diabetes


Further research builds upon the association of a vegetarian diet and lower risk of CVD and suggests that people adhering to a vegetarian diet have lower CVD mortality rates than do non-vegetarians. One prospective study involving 44,561 men and women from England and Scotland found that the vegetarian segment of the study population had a 32% (HR, 0.68) lower risk of ischemic heart disease (IHD) than did the non-vegetarians in the study, even after adjusting for factors such as age, smoking, alcohol, and physical activity.23 

After adjusting for BMI, vegetarians still showed a 28% (HR, 0.72) lower risk of IHD than did non-vegetarians. The probability of hospitalization or death due to IHD was 4.6% for vegetarians, compared with 6.8% for non-vegetarians.

In congruence with those data, a meta-analysis of five prospective studies found that vegetarians had a 29% (RR, 0.71) lower mortality rate from IHD than did non-vegetarians.24  In another example, a study of 73,308 men and women found that all types of vegetarians (semi-vegetarians, pesco-vegetarians, lacto-ovo vegetarians, and vegans) had significantly lower mortality rates compared with non-vegetarians.25 

A strength of this study was that all the subjects followed the same conservative religious principles of the Seventh-day Adventist Church, thereby reducing variables outside of their diet (such as tobacco and alcohol use) that may have led to poor health outcomes. 

The group was almost evenly split: 51.8% were vegetarian and 48.2% were non-vegetarian. The non-vegetarian mortality rate was 6.61 deaths per 1,000 person-years; pesco-vegetarians had the lowest mortality rate at 5.33 deaths per 1,000 person-years. Mortality from CVD and IHD were significantly reduced for male vegetarians.


Numerous studies have proven that a vegetarian diet can decrease a person’s risk of heart disease by reducing risk factors such as high cholesterol, high blood pressure, diabetes, and obesity, and can even reverse lesions of occlusive coronary artery disease

Moreover, patients at risk of CHD who adopt a vegetarian diet or modify their current diet by reducing meat intake can often reduce or even prevent the need for medications, thereby avoiding related adverse side effects.

Given the shift in our health-care model toward preventive medicine, interventions such as dietary modification to reduce the risk of CVD will be vitally important. Patients should be encouraged at every opportunity to make positive lifestyle changes. Those who are serious about changing their diets as part of a comprehensive treatment plan would likely benefit from referral to a registered dietitian. 

In addition, several websites serve as good resources for information on vegetarian diets, including the Vegetarian Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics, The Vegetarian Resource Group, the Jesse & Julie Rasch Foundation’s, and the Mayo Clinic’s “Nutrition and healthy eating” page.

Allison Nichols, PA-C, is a resident in the Physician Assistant Residency Program for Cardiothoracic Surgery at St. Joseph Mercy Hospital in Ann Arbor, Mich.

John Grosel, MD, is an associate professor in the Physician Assistant Program at Marietta College in Marietta, Ohio, and a radiologist with Riverside Radiology and Interventional Associates, Inc., in Columbus, Ohio.


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This article originally appeared on Clinical Advisor