Salt therapy, scientifically known as halotherapy, has been around for centuries in Eastern Europe and Russia, where people have long flocked to natural salt caves in hopes of easing symptoms of asthma, bronchitis, colds, and sinus infections. Today, artificial salt caves-climate-controlled rooms with walls made of slabs or bricks of salt-are found at some spas and stand-alone facilities in the U.S. Sometimes a misting device called a halogenerator sprays microparticles of salt into the air. Many people report that sitting in a salt room helps them relax and enhances their sense of well-being-but is there any evidence to support claims of medical benefits?
The origin of modern salt therapy can be traced to the mid-1800s, when a Polish physician observed that miners working in salt caves didn’t get the lung diseases common in other miners. A century later, a German physician found that people who hid in salt mines used as bomb shelters during WWII had improvements in respiratory conditions.
There are some ideas as to why salt therapy might help some respiratory conditions. According to the American Lung Association’s chief medical officer, inhaled salt could perhaps thin mucus in the airway, making it easier to expel. Other ideas are that the salt reduces inflammation and kills microbes in the lungs, reducing the risk of infections.
A 2014 review paper looked at the effect of salt therapy in chronic obstructive pulmonary disease (COPD). Only four studies were of high enough quality to be evaluated, and of them only one was a randomized controlled trial. Though some benefits were reported, the researchers concluded that there wasn’t enough good evidence to recommend salt therapy for COPD.
It’s claimed that salt therapy also soothes skin conditions such as eczema and psoriasis, but there is little, if any, evidence to back this. Some salt-room establishments unscrupulously promote their services for boosting immunity, improving athletic performance, aiding digestion, and other benefits-with no validation whatsoever.
Is it safe? Generally, yes. But the Asthma and Allergy Foundation of America notes that inhaling concentrated salts can irritate the airway, causing a buildup of mucus and coughing, which could worsen asthma symptoms. Other potential adverse effects include a constriction of the bronchial tubes that bring oxygen to the lungs. It’s also possible that chronically inhaling sodium might increase blood pressure and the risk of hypertension.
BOTTOM LINE: If you want to try salt therapy, it can be relaxing, but don’t expect it to cure any chronic illnesses, clear your skin, or make you a better athlete. If you have a chronic respiratory condition, hypertension, or other serious medical condition, talk to your doctor first.