A double-blind, placebo-controlled study published in the Journal of the American College of Nutrition (2005; 24(4):257–265) examined whether fermented dairy containing specific probiotic strains could influence blood pressure. The study included 80 adults with either high-normal blood pressure or mild hypertension.
Participants were randomly assigned to receive either powdered milk tablets fermented with Lactobacillus helveticus or a placebo for four weeks. Among subjects with mild hypertension, systolic blood pressure decreased by an average of 11.2 mm Hg. No significant change in systolic pressure was observed in those with high-normal blood pressure.
Diastolic blood pressure declined by an average of 5.0 mm Hg in the high-normal blood pressure group and by 6.5 mm Hg in participants with mild hypertension.
While the changes were modest, the findings are notable because they suggest that alterations in gut bacteria—through fermented foods or probiotics—may influence blood pressure regulation. This study adds to growing interest in the role of the microbiome in cardiovascular balance, although longer and larger studies are needed to better understand these relationships.
