People who eat a vegetarian diet tend to have lower blood pressure than non-vegetarians, according to a new review of past studies.
Researchers said a vegetarian diet could be a good way for some people to treat high blood pressure without medication.
Vegetarian diets exclude meat, but may include dairy products, eggs and fish. They emphasize foods of plant origin, particularly vegetables, grains, legumes and fruits.
High blood pressure contributes to risk of heart disease, stroke, kidney disorders and other health problems. For many people, the only treatment has been medication, but that means costs and possible side effects, lead author Yoko Yokoyama told Reuters Health in an email.
"If a diet change can prevent blood pressure problems or can reduce blood pressure, it would give hope to many people," Yokoyama said. She is a researcher at the National Cerebral and Cardiovascular Center in Osaka, Japan.
"However, in order to make healthful food choices, people need guidance from scientific studies," she said. "Our analysis found that vegetarian diets lower blood pressure very effectively, and the evidence for this is now quite conclusive."
According to the American Heart Association, blood pressure readings under 120 mm Hg systolic and 80 mm Hg diastolic (120/80) are considered normal. High blood pressure starts at 140/90.
The new review, published in JAMA Internal Medicine, combined results from 39 previous studies, including 32 observational studies and seven controlled trials.