Well the thing is, both salts (sodium & potassium) and sugar are required for hydration, or you can develop a severe fluid imbalance.
"Why not just drink water? Whether you’re sweating or ill with diarrhea, you’re not just losing water. You’re also losing electrolytes necessary for all the functions of the body. The most important of these are sodium and potassium. If you lose a lot of electrolytes and drink a lot of plain water to rehydrate, dangerous things can happen. In athletes, severe hyponatremia (low blood sodium) can lead to death"... Iodine is also lost in sweat, etc. So iodized salt would be a good idea, if iodine isn't in your diet or multivitamin otherwise. Too much salt isn't good, but neither is too little. Same goes for sugar (your brain needs glucose to function, and it helps with that fluid balance also).
Eating beets with salt will lower bp, in my experience.