If you're trying to get those blood pressure numbers down, a good place to start might be changing what you eat.
A new review of studies in JAMA Internal Medicine shows an association between eating a vegetarian diet and having decreased blood pressure levels, compared with eating an omnivorous diet.
Plus, researchers found that "the 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," they wrote in the study. A weight reduction of 5 kilograms is equivalent to about 11 pounds.
The review was conducted by researchers from the National Cerebral and Cardiovascular Center in Japan. They analyzed seven controlled trials and 32 observational studies to find that consuming a vegetarian diet is associated with a 4.8 millimeters of mercury decrease in systolic blood pressure in controlled trials, and a 6.9 millimeters of mercury decrease in systolic blood pressure in observational studies.
Meanwhile, consuming a vegetarian diet is associated with a 2.2 millimeters of mercury decrease in diastolic blood pressure in controlled trials and a 4.7 millimeters of mercury decrease in diastolic blood pressure in observational studies.
According to past research, a systolic blood pressure decrease of 5 millimeters of mercury would lower risk of dying from coronary heart disease by 9 percent, the risk of dying from stroke by 14 percent, and the risk of dying from all causes by 7 percent.
The researchers noted that other factors could possibly play a role in the association between vegetarian diet and decreased blood pressure, including the fact that vegetarians generally have lower body mass indexes and obesity risk than meat-eaters, and that vegetarian diets tend to be rich in potassium, which has been shown in other studies to lower blood pressure. Other potential factors: Vegetarian diets may generally be lower in sodium, vegetarians may consume less alcohol than the general population, and vegetarianism could affect the blood's viscosity (and thus have an impact on blood pressure).
More studies are needed to determine what kinds of vegetarian diets are best at lowering blood pressure, they said.