Consuming a vegetarian diet may be associated with lower blood pressure, and as such could be used to reduce blood pressure and heart disease risk, say researchers.

The meta-analysis of seven clinical trials and 32 studies in which participants consumed a vegetarian diet, finds consumption of a vegetarian diet is associated with lower blood pressure (BP).

Led by Dr Yoko Yokoyama from the National Cerebral and Cardiovascular Center, Japan, the team behind the analysis pooled measurements on net differences in BP associated with eating a vegetarian diet from 311 clinical trial patients and more than 21,000 participants in observational studies.

Writing in the journal JAMA Internal Medicine, Yokoyama and his team said that their results suggest such diets could be a useful nonpharmacologic means for reducing blood pressure.

“The meta-analysis indicates an overall difference in systolic BP of −4.8 mm Hg in controlled trials and −6.9 mm Hg in observational studies,” revealed the research team.

“These effect sizes are similar to those observed with commonly recommended lifestyle modifications, such as adoption of a low-sodium diet or a weight reduction of 5 kg, and are approximately half the magnitude of those observed with pharmaceutical therapy, such as administration of angiotensin-converting enzyme inhibitors to individuals with hypertension,”they added.

Yokoyama and colleagues commented that further studies are now required to clarify which types of vegetarian diets are most strongly associated with lower blood pressure, adding that research into the implementation of such diets, either as public health initiatives aiming at prevention of hypertension or in clinical settings, “would also be of great potential value.”

Source: JAMA Internal Medicine
Published online ahead of print, doi: 10.1001/jamainternmed.2013.14547 
“Vegetarian Diets and Blood Pressure: A Meta-analysis”
Authors: Yoko Yokoyama, Kunihiro Nishimura, et al