My family comes from Key West. My mother came from a very old family line of pharmacists from Cuba. She always used SALT to keep colds away as a little girl in the 1930's. She told us she would go down to the ocean and dip a glass bottle into the sea water to carry home for use.

Growing up, she used salt in our house to keep us free from sinus colds or mucus.

Salt is very beneficial when it's the right Salt.

https://youtu.be/XxPLWR1U5D0

My dad, as soon as we would arrive at the beach, no matter what time day or night, would head off down to the water for handfuls of ocean water to gargle ....said it was the only thing that would clear his sinuses.