Nutrition Notes

Linking Hypertension and the Gut Microbiome

A balanced gut microbiome has been shown to have many health benefits, which includes the strengthening of the gut barrier and the support of a healthy immune response. Gut microbiome dysbiosis has been linked to several disorders, including inflammatory bowel disease, type 1 diabetes, and other autoimmune conditions. Should we also think about the gut microbiome when we think about hypertension?

For almost 40 years, researchers have been contemplating the relationship between hypertension and gut health after an observed increase in blood pressure during antibiotic treatment, a known disruptor of the gut microbiome. A 2020 review article discusses the association between the microbiome and hypertension and proposes some possible connections.

The gut microbiome produces metabolites that have links to blood pressure regulation. Short chain fatty acids (SCFA) such as acetate, propionate, and butyrate are metabolites made only in the gut microbiome when digesting dietary fiber. SCFA have been shown to bind to certain olfactory receptors in the kidney, sending signals to play a role in renin secretion, an important molecule in blood pressure regulation. SCFA have also been shown to maintain the epithelial barrier, reduce sympathetic activity, and support a healthy inflammatory response.

In animal studies, spontaneously hypertensive rodents had a significant decrease in microbial diversity, suggesting a correlation between hypertension and the gut microbiome. Another study showed a significant decrease in systolic blood pressure in animals fed sour milk. Additionally, salt-sensitive hypertension has been shown in animal studies to be ameliorated by supplementation of Lactobacillus murinus through the modulation of T-helper 17 cells.

Human studies have shown equal promise. A systematic review and meta-analysis was performed to explore the effect of probiotic supplementation on blood pressure, pooling data from more than 2,000 human participants. Significant decreases in both systolic blood pressure (by −3.05 mmHg) and diastolic blood pressure (by −1.51 mmHg) were reported when probiotics were consumed by patients with certain conditions such as hypertension. Probiotics taken by patients for 8 weeks were shown to improve lipid levels, blood pressure, and inflammation indicators in a different meta-analysis.

The gut microbiome is not typically the first thought for the treatment of hypertension. However, research suggests that supplementation with probiotics or prebiotics may be useful and clinically relevant for it.

By Colleen Ambrose, ND, MAT