A high salt challenge (~2.36 g of sodium per day) reduced survival of various Lactobacillus species of gut bacteria, increased the number of autoimmune precursor cells, and elevated blood pressure in healthy males after 2 weeks (pilot study).

In mice, several intestinal bacteria were suppressed by high salt particularly, Lactobacillus strains. In addition, fecal bacterial tryptophan metabolites seem to play a role in increasing the quantity of precursor autoimmune cells (Th17 cells).

More research needs to be done to investigate how much of a role high sodium intake plays in the relative loss of Lactobacillus strains from gut microbiomes and development of hypertension and autoimmunity.