Vegetarian diets are associated with a significant reduction in the risk of mortality from ischemic heart disease, according to a new meta-analysis published in the American Journal of Preventive Cardiology.
The possible benefits—or detriments—of a meatless diet have been a contentious topic for decades now. That debate has continued in recent years; some studies have suggested a vegetarian diet can reduce all-cause mortality, but others have found no evidence of such a connection.
The authors of this latest analysis tracked data from eight different observational studies, covering more than 131,000 participants in total. The mean follow-up period was 10.68 years. Each study compared a vegetarian diet with a non-vegetarian diet, focusing on mortality outcomes and the risk of certain conditions.
Two independent researchers selected studies to use for this meta-analysis, starting with more than 600 studies and then making exclusions as necessary.
“The screening for relevant articles was performed at two levels,” wrote lead author Ahmad Jabri, MD, of the Heart and Vascular Center at Case Western Reserve University and MetroHealth Medical Center in Cleveland, and colleagues. “At the first level, titles and abstracts of searched citations were reviewed for relevance. At the second level, articles identified at level one of screening were subjected to a full-text review. Any disparity at the second level was solved by mutual consensus and in consultation with the senior authors.”
Overall, a vegetarian diet was consistently associated with a “significantly reduced risk of mortality due to ischemic heart disease.” However, vegetarian diets were not found to make a significant impact on a person’s risk of mortality due to cerebrovascular disease or all-cause mortality.
Jabri et al. noted that, over time, vegetarian diets have started including more processed foods and refined sugars. This, they argue, have helped lead to a decline in the “attributable health benefits” of such a diet.
In addition, they wrote, the reduced risk of mortality from ischemic heart disease may at least be party due to the fact that individuals following a vegetarian diet tend to make other lifestyle decisions that could benefit their heart.
“The motivational factor behind vegetarianism is usually underlined by the increased likelihood of adopting healthy habits,” the authors wrote. “Vegetarianism usually extends beyond the scope of a diet and becomes a lifestyle with shared health practices and behaviors. For instance, vegetarians self-reported that they are more likely to abstain from smoking, alcohol, and the use of prescription drugs than the general population. Additionally, 47% of participants in a study examining the lifestyle behaviors of vegans reported adopting this diet due to ‘health-related reasons.’”
The full analysis is available here.
Michael has more than 16 years of experience as a professional writer and editor. He has written at length about cardiology, radiology, artificial intelligence and other key healthcare topics.