Ages and ages and ages ago I wrote an initial blog post on halotherapy (salt cave therapy), and i promised you a follow up once I have looked at the available data for it.
In short, I always meant to get round to following it up, but kept forgetting or getting embroiled in something else instead. So here, dear friends, is the follow up post.
As you may recall, www.saltcave.co.uk were claiming their clinically tested, drug free treatment meant that many of their patients stopped taking their medications becuase they because symptom free. They claimed it would work for asthma, COPD, and sinusitis. So, I thought I'd test their claim for COPD, particularly since this illness can be particularly devastating and debilitating.
So here's what I did: had a look at their website, which attempts to helpfully provide a list of published studies. I the proceeded to ignore this entirely, and did my own search of Medline and Embase, the two leading medical literature databases in the world. If there was going to be any robust evidence, I would find it in those.
Now I'm interested in human clinical studies mainly as a starting point, because these are the ones that can actually tell us best whether or not something works. So I limited the searches to human trials: after all, The Salt Cave are claiming that it's a clinically tested therapy, right? I then combined the results for halotherapy, with results for chronic obstructive pulmonary disease, to see what would come up.
In Embase, I found one study. Unfortunately, it was in Russian, so I have to rely on the abstract. The study included 29 patients, and that's pretty much all that we know. The authors claim a significant positive effect, with no other information or data reported in the abstract. But frankly, a study with 29 patients in is neither here nor there- it's far too small to use to make any claims of benefit.It's worth noting, by the way, that these patients were in a "sanatorium" setting, which is likely to be a rather different setting to the middle-class-Ikea-£35 a go-UK based version that is being sold here. What other treatments would be given in a Russian sanatorium setting? How would any of this affect the patient's condition? How has this been controlled for in this study? Unfortunately, there's no way of knowing given how badly presented the abstract is.
Okay, so what did I find in Medline? Well, in short, nothing. No results at all.
So then I went back to the references provided by www.saltcave.co.uk and found very little to add. Another Russian-based sanatorium study, in abstract only, providing no data at al. Likewise, the study that they use on the "results" page of their website only include 26 patientswith COPD: again, too limited to draw any secure conclusions from.
So my conclusion? The evidence for the use of salt cave therapy in COPD is far too limited to claim any benefit at this point in time. More research needs to be done in this area to be able to claim that it works. And this evidence base certainly doesn't justify £35 per hour. They can put as many testimonials as they like on their website but it still doesn't add up to good, robust clinical evidence.
Hopefully this is a step to debunking some of the claims they are making on this website. Whilst there is a possibility that it might work, at the moment we just don't have enough information to justify the claims- and the cost.
Further reading on halotherapy can be found at The 21st Floor and Sceptical Letter Writer
For transparency, here's my search terms: EMBASE: halotherapy.ti.ab AND Chronic obstructive ling disease/ MEDLINE: halotherapy.ti.ab AND Pulmonary disease, chronic obstructive