As scientists study the trillions of bugs, most of them bacteria, living in our intestines—known as the “gut microbiome,” they’re finding that this 3-5 pound community of microbiota has important roles in just about everything that goes on in our bodies. Some scientists are even saying our microbiota may be more important than our genes in determining our health or lack thereof.
Recently, they’ve discovered that gut microbiota are intimately involved in determining blood pressure.
It’s well-known that excessive salt intake isn’t good for the heart and has been associated with elevated blood pressure. Studies done in the last few years indicate that it’s how salt influences the microbiome that ultimately affects blood pressure.
A 2017 study found that when either mice or humans ate too much salt, good bacteria in the gut started disappearing while pro-inflammatory immune cells called TH-17 cells started to rise; and as they did, they raised blood pressure. But when probiotics were given to these mice or humans, it reversed the situation—as the good bugs in the microbiome increased, the TH-17 cells decreased and so did blood pressure.
How much salt are we talking about? For the humans it was about 1 teaspoon of salt (2,300 milligrams of sodium) added to the diet.
A second study done last year with a group of untreated hypertensives found that when they reduced their sodium intake to about 2,000 milligrams a day, they produced more short-chain fatty acids (SCFAs) in their guts and their blood pressure went down.
Abundant production of SCFAs is a marker for a healthy gut microbiome. SCFAs are fermented from fiber by good bacteria; they help to keep the gut healthy through their anti-inflammatory effects and by maintaining strong intestinal walls. But SFCAs are also released into the bloodstream and travel to the heart and kidneys. Increased SCFAs are consistently associated with lower blood pressure and greater blood vessel flexibility.
In this study, women hypertensives were more “salt-sensitive” than the men; their systolic blood pressure (the top number that measures pressure when the heart contracts) decreased 5 points with reduced salt consumption, while only 3 points for the men.
Finally, a third study involving data from almost 7,000 participants, found that those with high blood pressure had less diversity in their microbiomes and a different microbe composition. Quite a few of the lactobacillus bacteria (good guys) were associated with lowered blood pressure, particularly Lactobacillus paracasei.
So what to make of these recent findings? Moderation with the salt shaker seems to be a good idea; we’ve generally recommended about ½ a teaspoon a day of Celtic Sea Salt.
But these findings also point to the importance of maintaining a flourishing gut population of healthy bacteria. Most importantly this involves eating a low-sugar, high-fiber diet; avoiding antibiotics when possible; eating lots of green vegetables; and taking a high-quality probiotic supplement.
Beyond Health’s Probiotic Formula supports optimal gut health with 10 strains of living, healthy, viable probiotics, including Lactobacillus paracasei.
- Wilck N. Salt-responsive gut commensal modulates TH17 axis and disease. Nature. November 2017; 551(7682): 585-589.
- Chen L. Modest sodium reduction increase circulating short chain fatty acids in untreated hypertensives. A randomized, double-blind, placebo-controlled trial. Hypertension. June 2020; 76(1): 73-79.
- Palmu J. Association between the gut microbiota and blood pressure in a population cohort of 6,953 individuals, Journal of the American Heart Association. August 2020; 9(15): 1-9.