Vegetarian diet may improve ischemic heart disease but not all-cause mortality: Study

Cardiovascular Disease (CVD) has the highest mortality rate at an early age across the world. The risk factors including high blood cholesterol, smoking, and obesity are well known. Diet plays a vital role in monitoring cardiac health.

Vegetarian diet is much favorable in improving cardiac health though animal protein intake has no opposition, finds a new study by Dr Ahmad Jabri and his team. 

The study has been published in The American Journal of Preventive Cardiology.

The objective of the study was to summarize the association between vegetarian versus non-vegetarian diet on mortality due to ischemic heart disease, cerebrovascular disease, or all-cause mortality. Dietary improvement of cardiac health is a much feasible way. The study was conducted at Heart and Vascular Center, Case Western Reserve University/MetroHealth Medical Center, Cleveland, OH, USA.

The Researchers used PubMed, Cochrane databases, and ClinicalTrials.Gov from the inception of the databases to October 2019 with no language restriction. Randomized controlled trials or prospective observational studies were used for comparing the association between vegetarian versus non-vegetarian diets among adults and reporting major adverse cardiovascular outcomes was selected. Paule-Mandel estimator was used for tau2 with Hartung–Knapp adjustment for the random-effects model to estimate risk ratio [RR] with 95% confidence interval [CI]. The primary outcome of interest was all-cause mortality. The secondary outcome was ischemic heart disease mortality.

The researchers did eight observational studies ( n = 131,869) which were included in the analysis. Over a weighted mean follow-up of 10.68 years, very low certainty of evidence concluded that a vegetarian diet compared with a non-vegetarian diet was associated with a similar risk of all-cause (RR: 0.84, 95% CI: 0.65–1.07, I 2: 97%) or cerebrovascular mortality (RR: 0.84, 95% CI: 0.63–1.14, I 2: 90%), but was associated with a reduced risk of ischemic heart disease mortality (RR: 0.70, 95% CI: 0.55–0.89, I 2: 82%).

The researchers concluded that "A vegetarian diet, compared with a non-vegetarian diet, was associated with a reduced risk of ischemic heart disease mortality, whereas it did not affect all-cause and cerebrovascular mortality. However, the results are to be considered with caution considering the low certainty of evidence. Despite recent studies supporting no restriction on animal protein intake gaining wide media attention and public traction, consideration for vegetarianism amongst those with risk factors for coronary artery disease should be contemplated."

For further information:

Ahmad Jabri, Ashish Kumar, Elizabeth Verghese, Anas Alameh, Anirudh Kumar, Muhammad Shahzeb Khan, SafiU. Khan, Erin D. Michos , Samir R. Kapadia , Grant W. Reed, Ankur Kalra. " Meta-analysis of effect of vegetarian diet on ischemic heart disease and all-cause mortality" American Journal of Preventive Cardiology 7 (2021) 100182.