Halotherapy and Speleotherapy: What the Trials Actually Show for Asthma, COPD, and Skin Claims

What halotherapy and speleotherapy actually are

Speleotherapy is time spent in natural salt caves or former salt mines, originally observed in Central and Eastern Europe among miners who seemed to have lower rates of respiratory complaints. Halotherapy is the modern, manufactured version: a room or cabin where a halogenerator disperses dry sodium chloride particles into the air, meant to approximate a cave microclimate without the travel or the mine.[6]

As a practice, sitting in a controlled, low-stimulation room breathing salt-laden air is safe for most healthy adults and is not a medical procedure with meaningful risk. That is different from saying it treats a disease. Every claim about asthma, COPD or skin conditions needs its own evidence, separate from the fact that the room itself is pleasant and low-risk.[6]

What the asthma and speleotherapy trials actually show

The Cochrane review of speleotherapy for asthma looked at three randomized trials in 124 asthmatic children. Only one of the three was judged to have reasonable methodological quality, and the reviewers concluded the evidence was insufficient to determine whether speleotherapy works for chronic asthma. That review has not been meaningfully updated since 2006, so it represents the ceiling of what older trial data can tell us, not a current verdict.[1]

A better-designed pediatric pilot in 2017 randomized 55 children to real halotherapy or a sham cabin. Bronchial hyper-responsiveness and most quality-of-life domains improved more in the halotherapy group. But the study's own primary lung-function markers, spirometry and exhaled nitric oxide, did not improve compared to sham. The authors describe it explicitly as a pilot.[3]

A 2021 narrative review of 18 studies summarizes generally favorable short-term signals across the halotherapy literature, but the authors themselves note that current asthma guidelines only reference hypertonic saline as a diagnostic bronchial-challenge tool, not as a therapy, and that the studies reviewed involve small participant numbers that limit how far the findings generalize.[6]

The one trial designed to separate salt from everything else was negative

A 2020 randomized controlled trial gave the cleanest test of speleotherapy's own contribution. Adults with allergy or asthma were randomized to a winter exercise program either combined with speleotherapy sessions or exercise alone. Quality of life and symptoms improved over time in both groups, with no significant difference between them. The authors state plainly that the observed benefits were combined winter-exercise effects, not something speleotherapy added on top.[4]

This matters because it is the only trial in this evidence base built specifically to isolate the salt-cave exposure from confounders like exercise, routine, and altitude. When that isolation was attempted, the salt-specific effect disappeared. The authors also note the study was underpowered by their own calculation, so a small true effect could not be ruled out, but it also was not found.[4]

COPD, ENT complaints, and skin conditions have their own thin evidence

A systematic review of halotherapy for COPD found only one randomized trial and three case-control studies, totaling 1,041 participants. Some studies reported signals on respiratory function and quality of life, but the review flagged poor methodological quality throughout and concluded that recommendations for practice cannot be made at this point.[2]

In children with sub-obstructive adenotonsillar hypertrophy, a double-blind placebo-controlled trial of 45 children missed its primary endpoint. A secondary endpoint, reduction in hearing loss, reached statistical significance, which is a real finding worth noting but also the kind of secondary result that needs replication before it becomes a claim.[5]

For skin conditions, the only located source is a 1994 Russian-language case series of 112 children with atopic dermatitis, reporting complete response in 58 percent and partial response in 20 percent after speleotherapy. It was not randomized or blinded, the full methodology is not accessible, and no modern controlled trial for atopic dermatitis, psoriasis, or any other skin condition could be found. This is not evidence AION would consider adequate to support a skin claim today.[7]

What this means for you

AION offers halotherapy as what it actually is: a private, low-stimulation salt cabin used as a recovery pause, not as a respiratory or dermatological treatment. The evidence above does not support marketing halotherapy as a therapy for asthma, COPD, or skin disease, and AION does not make those claims.[4][2]

For anyone with diagnosed asthma, COPD, or a skin condition who is curious about halotherapy, the physician-led approach is to keep it separate from, not a substitute for, guideline-based respiratory or dermatological care, and to be honest that the best-controlled trial available found no treatment-specific benefit once exercise and routine were accounted for. There is no fixed halotherapy protocol claimed to work at AION, because the trial evidence does not support one.[3][4]