Salt is dangerous when you don't balance it with calcium, magnesium and potassium. Doctors only see high sodium. They never consider that the others are low. Balance is the key.
As for sea salt....It's just scum off the bottom of the ocean. It's scraped up from the sea floor. It is full of bacteria and parasites. No person who has watched it be harvested would eat that stuff. It's just a crazy get rich scam. So gross.
Rock salt has the same issues as it comes from ancient sea beds. The good thing is that thousands of years have reduced the bacteria and parasite content.
Sodium is necessary for the function of all body systems. You must balance the complimentary minerals. Most people are deficient in magnesium and potassium. THIS is the cause of heart failure.