Probiotics May Reduce Blood Pressure Moderately

A new study suggests that probiotics reduce blood pressure (BP) by approximately 4 mm Hg systolic and 2 mm Hg diastolic on average. The effect was greater in people with hypertension, and when the probiotics taken contained multiple species of bacteria.

Lead author Jing Sun, PhD, and colleagues at the School of Medicine and the Griffith Health Institute of the Griffith University in Gold Coast, Queensland, Australia, performed the meta-analysis, which was published online July 21, 2014, in Hypertension: Journal of the American Heart Association.

“We believe probiotics might help lower blood pressure by having other positive effects on health, including improving total cholesterol and low-density lipoprotein, or LDL, cholesterol; reducing blood glucose and insulin resistance; and by helping to regulate the hormone system that regulates blood pressure and fluid balance,” Sun said.

The study included 9 randomized, controlled trials that reported BP effects of probiotic products with live cultures in 543 adults with or without hypertension. Study durations were 3 to 9 weeks.

However, the study had variable interventions and populations. Trials included only healthy subjects, others enrolled patients with hypercholesterolemia and obesity and metabolic syndrome. Interventions involved yogurt as the probiotic, fermented and sour milk, supplement capsules, drinks, and cheese. Several studies used single-species probiotics while the remainder used combination of 2 or 3 strains. The total daily dose of probiotics ranged as well.

“The studies looking at probiotics and blood pressure tend to be small,” Sun said. “Moreover, 2 studies had a short duration of 3 to 4 weeks of probiotic consumption, which might have affected the overall results of the analysis.”

The study concluded that consuming probiotics may improve BP by a modest degree, with a potentially greater effect when baseline BP is elevated, multiple species of probiotics are used, and the duration of the intervention is at least 8 weeks, or daily consumption with bacteria volume of ≥10¹¹ colony-forming units.