We hear about salt being bad for us (sodium chloride). But there are many other salts which may be consumed in large quantities on a daily basis, e.g. pharmaceuticals.
Is it specifically sodium chloride that's the culprit or any chemical salt?
We hear about salt being bad for us (sodium chloride). But there are many other salts which may be consumed in large quantities on a daily basis, e.g. pharmaceuticals.
Is it specifically sodium chloride that's the culprit or any chemical salt?
Terminology in Context
It is important to distinguish between technical or scientific usage of terminology and popular usage of terminology in the 'lay' literature.
When physicians, news articles, etc, refer to "salt" in dietary contexts, they are almost always referring to common salt also known as table salt and consisting of sodium chloride, NaCl, rather than referring to the chemical term "salt".
In most contexts, they are also intending to refer primarily to the sodium content of table salt, rather than the entire species NaCl, simply because NaCl is the primary dietary source of sodium ions for a typical human. They are also likely referring to the average overintake of sodium in a common diet: high sodium carries risks, but taking zero sodium would also be deadly: sodium is a very necessary ion in human biology.
Other Salts
"Salts" in general are an incredibly broad class of chemicals, and some of them can be quite toxic. Potassium cyanide, for example, is a salt - it is quite lethal for you to ingest once it turns to hydrogen cyanide in the stomach.
In a dietary context, a salt like potassium chloride could be seen as less harmful than sodium chloride, because it is not going to have the same impact on blood pressure and because potassium is more often too low in typical diets - but it won't taste exactly like sodium chloride.
The meaning of 'bad for you' is context-dependent
However, on a toxicity/poison level, potassium chloride (LD50=2.5 g/kg) is slightly more deadly than sodium chloride (LD50=3.75 g/kg) administered orally, and much more deadly intravenously. Potassium chloride is the final drug administered in some lethal injection protocols: high blood potassium concentrations, higher than you would obtain through normal consumption of potassium in food, stops muscle and nervous activity, including that of the heart.
In summary, if you are going to ingest a whole lot of something right this moment, or especially if you are injecting something into an IV, you would be safer with sodium chloride than potassium chloride. On the other hand, it is likely that a lifetime diet that is somewhat higher than recommended in sodium chloride is going to be far more dangerous than a lifetime diet that is somewhat higher than recommended in potassium chloride.
Back to sodium...
As far as the harm of sodium itself, it doesn't matter much what ions you ingest sodium with: sodium chloride versus sodium bicarbonate contributes an equivalent amount of sodium to your diet if you adjust for the difference in molecular weight (that is, the mass of the bicarbonate ion is bigger than the mass of the chloride ion, so it takes more sodium bicarbonate to get the same amount of sodium).
In most pharmaceutical applications, though, the sodium content is simply not meaningful in a dietary context.