We all know that too much salt in the diet isn’t good for health. High salt levels can lead to high blood pressure and cardiovascular disease. New studies in mice and humans by researchers in Germany, the U.S. and Belgium, have now shown that high levels of dietary salt also strip the microbiome of specific bacteria. The results suggest that taking tailored probiotics to replace the missing bacteria could help to reduce hypertension induced by a diet high in salt and have more wide-ranging benefits, possibly even as an addition to existing therapies for autoimmune disorders.
“Multiple sclerosis may be one of the salt-sensitive diseases that we might be able to treat in the future with individually tailored probiotics as add-on to standard immune therapies,” states co-researcher Prof. Ralf Linker, a professor in the department of neurology, Friedrich-Alexander-University Erlangen-Nuremberg, Germany. The interdisciplinary research team reports its findings in Nature, in a paper entitled “Salt-responsive gut commensal modulates TH۱۷ axis and disease.”
High dietary salt levels have been found to induce proinflammatory T helper 17 (TH۱۷) cells, which have been linked with hypertension and also play a damaging role in certain autoimmune disorders. Changes in diet can also lead to either temporary or long-term changes to gut microbiome composition, which can have “profound effects” on T cells, the researchers write. “TH۱۷ cells are particularly affected by the abundance of specific commensal bacteria.”
What hasn’t been studied before is the direct effect of dietary salt on the gut microbiome, notes Dominik Müller, Ph.D., at the Berlin Experimental and Clinical Research Center (ECRC) and the Berlin Institute of Health (BIH) within the Max Delbrück Center for Molecular Medicine and the Charité – Universitätsmedizin Berlin. The researchers, headed by Müller’s team, compared the gut microbiomes of mice fed either a normal or high-salt diet.
A Large Order of Gut Microbes, Hold the Salt