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Interesting idea - that perhaps our community of gut microbes being out of whack (dysbiosis) leads to hypertension. This study was done in both humans and mice - with an analysis of bacteria in both hypertensive individuals and pre-hypertensives, and also healthy individuals (the controls). Then the microbes from 2 hypertensive individuals were transplanted into mice (fecal microbiota transplants). And lo and behold - the mice became hypertensive with an alteration of their gut microbes. This is amazing!

The study showed that transplanting microbes from hypertensives to non-hypertensives caused an elevation in blood pressure in the formerly healthy group. This shows the direct influence of gut microbes on blood pressure. The bacteria found in both the pre-hypertensives and hypertensives (especially an overgrowth of Prevotella and Klebsiella bacteria) are those linked to inflammation. And what kind of diet is linked to that bacteria? A high fat diet. Yes, the Western diet with lots of fat and highly processed foods.

The researchers talked about other research also showing Prevotella being associated not only with hypertension, but also other diseases (e.g., periodontal diseases and rheumatoid arthritis). On the other hand, Faecalibacterium, Oscillibacter, Roseburia, Bifidobacterium, Coprococcus, and Butyrivibrio, which were "enriched" in healthy controls, were lower in pre-hypertensive and hypertensive persons. In the past I have posted about a "special" bacteria that is even called  a "keystone" gut bacteria - Faecalibacterium prausnitziithat is linked to health and is low or absent in the gut in a number of diseases ((here and here). It is not available in a supplement at this time (because it dies within a few minutes upon exposure to oxygen), but diet influences it. A high animal meat, high animal fat, high sugar, highly processed foods, and low fiber diet (the typical Western diet) lowers F. prausnitzii numbers, while a high-fiber, low meat diet increases F. prausnitzii numbers.

What you can do: Feed the beneficial gut microbes by increasing the amount of fruits, vegetables, whole grains, seeds, nuts that you eat. And cut back on the greasy, high fat processed and fast foods.

The following excerpt is misleading - for example, it ignores the first part of the actual study which looked at the gut bacteria of pre-hypertensives, hypertensive, and healthy people. Then gut bacteria from hypertensive people were transplanted into healthy mice, and gut bacteria from healthy people were transplanted into hypertensive mice. Also, it wasn't rats, but mice used in the study. It goes to show why it's important to look at original studies - not just believe articles out there blindly. [See original study.] From Science Daily: Unhealthy gut microbes a cause of hypertension, researchers find

Researchers have found that the microorganisms residing in the intestines (microbiota) play a role in the development of high blood pressure in rats mice....Scientists studied two sets of rats mice, one group with high blood pressure ("hypertensive") and one with normal blood pressure ("normal").... All animals were then given antibiotics for 10 days to reduce their natural microbiota. After the course of antibiotics, the researchers transplanted hypertensive microbiota to normal blood pressure rats mice and normal microbiota to the hypertensive group. 

The researchers found that the group treated with hypertensive microbiota developed elevated blood pressure. A more surprising result is that the rats mice treated with normal microbiota did not have a significant drop in blood pressure, although readings did decrease slightly. This finding is "further evidence for the continued study of the microbiota in the development of hypertension in humans and supports a potential role for probiotics as treatment for hypertension," wrote the researchers. "Studies showing that supplementing the diet with probiotics (beneficial microorganisms found in the gut) can have modest effects on blood pressure, especially in hypertensive models."

NOTE that the actual study said in its CONCLUSIONS:  "Taken together, we have described clearly the disordered profiles of gut microbiota and microbial products in human patients with pre-hypertension and hypertension, established the relationship between gut dysbiosis and hypertension, and provided important evidence for the novel role of gut microbiota dysbiosis as a key factor for blood pressure changes. Our findings point towards a new strategy aimed at preventing the development of hypertension and reducing cardiovascular risks through restoring the homeostasis of gut microbiota, by improving diet and lifestyle or early intervening with drugs or probiotics."

Try to avoid triclosan. Read labels (especially soaps, personal care, and household cleaning products) and avoid anything that says it contains triclosan, or is anti-bacterial, anti-fungal, anti-microbial, or anti-odor. We easily absorb triclosan into our bodies, and it has been detected in our urine, blood, and breast milk. Among its many negative effects (e.g., here and here) is that it is now linked to disruption of gut bacteria.

The gut microbiome performs vital functions in our bodies. Deviation from the normal microbiome (our microbial communities being out of whack) is known as dysbiosis. Dysbiosis has been associated with human diseases, including diabetes, heart disease, arthritis, and malnutrition. The researchers used zebrafish because they are commonly used to study impacts of various chemicals on gut microbial communities. So yes, the findings are valid and match what other studies have found. So please try to avoid triclosan. From Science Daily:

Common antimicrobial agent rapidly disrupts gut bacteria

A new study suggests that triclosan, an antimicrobial and antifungal agent found in many consumer products ranging from hand soaps to toys and even toothpaste, can rapidly disrupt bacterial communities found in the gut.The research was published in PLOS ONE by scientists from Oregon State University. It was based on findings made with zebrafish, which researchers believe are an important animal model to help determine possible human biological and health impacts of this antimicrobial compound.

Triclosan was first used as a hospital scrub in the 1970s and now is one of the most common antimicrobial agents in the world, found in shampoos, deodorants, toothpastes, mouth washes, kitchen utensils, cutting boards, toys, bedding, socks and trash bags. It continues to be used in medical settings, and can be easily absorbed through the skin.

"However, there's now a growing awareness of the importance of the bacteria in our gut microbiome for human health, and the overuse of antibiotics that can lead to the rise of 'superbugs.' There are consequences to constantly trying to kill the bacteria in the world around us, aspects we're just beginning to understand."

In the new study, researchers found that triclosan exposure caused rapid changes in both the diversity and composition of the microbiome in the laboratory animals. It's not clear what the implication may be for animal or human health, but scientists believe that compromising of the bacteria in the intestinal tract may contribute to the development or severity of disease. Some bacteria were more susceptible to the impact of triclosan than others, such as the family Enterobacteriaceae; and others were more resilient, such as the genus Pseudomonas.

The gut-associated microbiome performs vital functions for human health, prevents colonization with pathogens, stimulates the development of the immune system, and produces micronutrients needed by the host. Dysfunction of this microbiome has been associated with human disease, including diabetes, heart disease, arthritis and malnutrition, the scientists pointed out in their study.

Triclosan has been a concern in part because it is so widely used, and it's also readily absorbed through the skin and gastrointestinal tracts, showing up in urine, feces and breast milk. It also has been associated with endocrine disruption in fish and rats, may act as a liver tumor promoter, and can alter inflammatory responses.