A rise in serum sodium from 140 to 142 mmol/L can acutely increase blood pressure by approximately 6 mmHg.

“when you eat salt like if you eat a salty soup the salt concentration goes up in your blood first and it translates into a thing called osmolality and so your serum osmolality goes up so osmolality is sort of like the ionic pressure buildup in a fluid is that a weighted it's sort of like the number of molecules in a set of volume so literally when you eat salt if it's really salty let's say you have a serum sodium concentration of 140 millimoles per liter if you eat a really salty soup your serum sodium may go up to 142 or 143 what looks like pretty insignificant but that actually is what triggers a rise in blood pressure”