Probiotics may lower blood pressure

Probiotics -- the healthy bacteria found in yogurt and certain dietary supplements -- may lower blood pressure levels. According to a new study, published in the journal Hypertension, taking supplements with live microorganisms that are also found in the human gut could be beneficial for people with high blood pressure and also help to improve overall cardiovascular health.

In a retrospective analysis, researchers looked at nine prior studies that examined the impact of probiotics on blood pressure levels. Overall they found routine probiotic use for at least eight weeks could lower systolic blood pressure (the top number) by three and a half points and diastolic blood pressure (the bottom number) by more than two points. A positive change in diastolic blood pressure was greatest in people with a base blood pressure of 130/85.

"Over a large group of people, when you look at a population, a lower blood pressure by even two or three points can have an impact on important things: the risk of stroke, death and heart attack. So we take very seriously a small decrease in blood pressure," Dr. Harmony Reynolds, a cardiologist at NYU Langone Medical Center, told CBS News.

Additionally, this analysis and other studies suggest that a probiotic supplement with multiple types of bacteria may be more beneficial to a person's health than those with only a single kind of bacteria. The bacteria load in the supplement also appears to be important. Pills with less than 109 colony-forming units of bacteria had less of an impact on blood pressure than those with at least or more than 109 units of bacteria.

The authors of this analysis speculate probiotics may lower blood pressure by helping to improve total cholesterol and lipoprotein levels, and also by reducing blood glucose and insulin resistance and regulating other hormone levels.

However, they note additional studies would need to be conducted, since the data used for this current analysis was based on small studies which together accounted for only 543 adults.

A growing body of research finds "good" bacteria benefits more than just the digestive system. Studies have linked healthy gut flora to clearer skin, successful weight loss, chronic pain relief and fewer bouts of the flu.

Reynolds and many other doctors aren't certain bacteria found in probiotic supplements offer as much benefit as the microorganisms that occur naturally in foods such as yogurt, sauerkraut and even pickles and kimchee. Some suggest the way to get the most benefit is to take supplements but also eat foods rich in the bacteria.

"Sometimes if people change their diet, exercise more, and probiotic is part of that healthy eating plan, they can avoid medicine, and I love to see that," said Reynolds.