The first thing to remember is when measuring that sodium and salt are different, 2.5g of NaCl salt contains 1g of sodium.

This paper may also pick up that people with various cardio vascular issues are more likely to be on a lower sodium diet. They are already ill.

This may be further highlighted as it reports "all-cause mortality was inversely associated with sodium intake", those who are healthy don't restrict salt as they feel immortal and don't worry about it.

Unfortunately this is the sort of paper that get traction with a certain group on Social Media because it's hidden and can be twisted to "recommend" you take more salt.

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