There is no scientific evidence that salt therapy will improve asthma or other lung conditions.
We can trace back the history of natural salt caves as an asthma remedy to ancient times. 'Salt rooms' have opened in parts of the U.S., Australia, the U.K., and elsewhere. Salt therapy (also known as halotherapy) involves a person relaxing while fine salt particles are dispersed into the room. It is believed it will help open up the airways and assist with the buildup of mucus, making it easier to breathe and improve a variety of skin and respiratory conditions, including asthma. The main drawback is that the therapy is not rigorously studied and contains incomplete information. Studies evaluating salt therapy for asthma are few, with just one randomized controlled trial conducted until now. Further, experts have identified several quality concerns about the reviews.