Can prebiotics reduce blood pressure?
In an Australian study published in 2023, researchers examined the potential for prebiotics to reduce blood pressure.
The study involved 21 participants who received either 40g of the prebiotic acetylated and butyrylated high-amylose maize starch (HAMSAB) supplementationor a placebo. The trial aimed to see if the prebiotic could influence blood pressure. Interestingly, while there were no significant changes in blood pressure when participants were assessed in a medical setting, there were intriguing results when their blood pressure was measured at home over the 21-day period.
People taking the resistant starch enriched prebiotic experienced a reduction in their home systolic blood pressure (the higher number in a blood pressure reading). This reduction was around -4.6 mmHg when comparing the beginning of the diet to the end, and even more notable reductions were seen when comparing the first few days of the diet to day 14. On the other hand, those on the placebo diet did not show significant changes in blood pressure at home.
The study also explored the gut health aspect by looking at the gut microbiome and the presence of SCFAs in the bloodstream. The prebiotic enriched diet did lead to an increase in specific SCFAs in the participants’ blood, indicating that the diet was successfully delivering these compounds. Additionally, the diet seemed to influence the gut microbiome, with certain species associated with SCFA production becoming more abundant in participants on the SCFA-enriched diet.
What are short chain fatty acids?
Short-chain fatty acids (SCFAs) are a group of organic compounds produced by the fermentation of dietary fiber by gut bacteria in the colon. They have several important roles in gut health, including potential benefits for “leaky gut” or increased intestinal permeability. Here’s how SCFAs may help with leaky gut:
Maintaining Gut Barrier Integrity:
SCFAs, particularly butyrate, play a crucial role in maintaining the integrity of the intestinal barrier. They promote the production of tight junction proteins, which help seal the gaps between intestinal cells. This tight junction reinforcement can reduce the permeability of the gut lining, preventing unwanted substances from passing through.
Anti-Inflammatory Effects:
SCFAs have anti-inflammatory properties. They can help reduce the production of pro-inflammatory cytokines and promote the generation of anti-inflammatory substances. Chronic inflammation in the gut can contribute to leaky gut, and by reducing inflammation, SCFAs may help mitigate this issue.
Immune Regulation:
SCFAs can modulate the immune system. They promote the development of regulatory T cells (Tregs), which are crucial for maintaining immune tolerance and preventing excessive immune responses. Dysregulation of the immune system can contribute to intestinal permeability, and SCFAs may help regulate it.
Energy Source for Colonocytes:
Butyrate, one of the SCFAs, is a primary energy source for the cells lining the colon (colonocytes). When colonocytes have sufficient energy from butyrate, they can function optimally, which contributes to maintaining a healthy gut barrier.
Balancing Gut Microbiota:
SCFAs can influence the composition of the gut microbiota. A balanced and diverse gut microbiome is crucial for gut health, and an imbalance can contribute to intestinal permeability. By promoting the growth of beneficial bacteria, SCFAs may help maintain a healthy gut microbiota.
Despite these promising findings, markers of inflammation in the participants’ blood did not change significantly, suggesting that the diet’s effect on inflammation might be more complex and require longer intervention periods.
Overall, this study provides interesting insights into the potential connection between gut health, SCFAs, and blood pressure regulation. While more research is needed to confirm these findings and understand the underlying mechanisms, the results suggest that our gut health could play a role in how our body regulates blood pressure. This has the potential to open up new avenues for managing high blood pressure and reducing the risk of related health issues like heart attacks or strokes.
Dr. Snelson suspects that individuals with resistant hypertension might have an even more permeable gut.
How do the prebiotics reduce blood pressure? Possible role of leaky gut:
New research funded by the Heart Foundation for World Hypertension Day 2023 aims to investigate whether poor gut health contributes to high blood pressure. Led by Dr. Matthew Snelson at Monash University, the study explores the possibility of a “leaky gut” in people with high blood pressure, where the gut becomes overly permeable, allowing harmful microbes to enter the bloodstream and cause inflammation. Dr. Snelson suspects that individuals with resistant hypertension might have an even more permeable gut. The research is grounded in emerging animal model evidence that suggests a link between leaky gut and high blood pressure. Since prebiotics are a well established way to promote the production of gut healing short chain fatty acids, healing leaky gut may be one pathway that prebiotics reduce blood pressure.