I was picking up a few things in my local health store a while ago when I noticed these gorgeous pink lamps. The store employee told me it was a “Pink Himalayan Salt Lamp” and made some pretty hefty health claims such as improving energy, treating asthma and generally cleansing the air.
I’ve been considering buying one for a while (mostly because they’re pretty) but I found the associated health benefits hard to believe. After all, it is just a lump of salt with a light bulb inside. Before dropping $50 on one, I examined the science behind the amazing benefits of pink Himalayan salt lamps.
What Is a Pink Himalayan Salt Lamp?
These products are made from salt originating in the Pakistani Khewra Salt Mine, which isn’t actually in the Himalayas. The pink colour comes from the presence of iron oxide, i.e. rust. This ain’t your common table salt – it began to form over 250 million years ago when the continental shelves collided to form a mountain range. For me, that’s a cool enough reason to buy one. (source)
The chunk of salt is usually hand-carved, depending on the maker. The center is hollowed out and an incandescent light bulb or candle placed inside. When lit, the lamp emits a soft, warm glow. (source)
What Are the Health Claims Associated with Pink Himalayan Salt Lamps?
Most of the sites providing information about the benefits of pink Himalayan salt lamps were selling them – not exactly a neutral source. One claim common to every site I looked at is that the lamps release negative ions. Lets look at this, and some other common claims in more detail.
1. Release of Negative Ions
Negative ions are simply particles with a chemical charge. They occur naturally very frequently. In fact, salt itself – sodium chloride – is made up of a negative ion of chloride and a positive ion of salt. They’re pretty strongly bonded together. Let’s get one thing straight. There’s no scientific evidence to say that these lamps produce negative ions.
Victor Stenger, a professor of physics and astronomy at the University of Hawaii puts this theory to rest, saying: “it’s not possible for a chunk of salt to release a significant amount of negative ions.
There isn’t nearly enough energy in a lamp to break up the ionic bonds between the sodium and chlorine in salt. If that were true, we’d have chlorine gas coming out our salt shakers.” (source) Measurement of ions backs this up – the amount released is close to zero. (source)
2. Air Purification
Many people are convinced that odors disappeared and dust in their home vanished after buying a Himalayan salt lamp. There are a few different explanations given for this. Firstly – some sites say the negative ions attach to dust and allergens, making them drop out of the air. Well, we know there aren’t a significant amount of ions released, and even if there were, they’re pretty much weightless so this is impossible.
Another explanation is that the salt draws water from the air onto its surface. It’s true that salt is hygroscopic – meaning it attracts water. The heat from the light bulb may release the water vapour back into the air while retaining the impurities. (source)
3. Increases Energy and Wellbeing
The example usually used here is that negative ions are released by natural phenomenon such as waterfalls, waves and thunderstorms. (source) Who doesn’t feel good when they’re looking at a waterfall? If you’re at that point you’ve probably had to hike there so you’re full of energy. I don’t know how much of this effect you can actually attribute to ions.
There are some claims that negative ions increase flow of oxygen to the brain – reducing drowsiness and improving alertness. (source) I couldn’t find any studies to back this up but let’s give it the benefit of the doubt. Even if this is true, the lamp can’t release negative ions so it’s moot.
4. Relieves Symptoms of Asthma
Asthma can be triggered by dust, pet dander, mold and mildew. (source) The drying effect of the lamp on the air may reduce the amount of bacteria to some extent but the effect would be limited to a very small area.
2 studies have shown that negative ions have no effect on asthma here and here. Not that these lamps can even produce ions. So don’t ditch the inhalers just yet (actually, don’t do that at all, because asthma attacks can be life-threatening).
5. Treats Seasonal Affective Disorder
We’ve already established that there’s no way these lamps are releasing ions that improve your mood. There is a chance that the unique colour of light emitted from the lamp can have a soothing effect for people suffering from low mood as a result of decreased daylight hours (seasonal affective disorder, SAD). There haven’t been any studies to test this but it’s possible. (source)
6. Reduces Static Electricity in the Air
When you get a small shock from a door handle or another person, this is static electricity. Ions are involved in this process, indeed, however we’ve determined that Himalayan salt lamps don’t produce ions so they can’t help with this. (source)
I was disappointed that the amazing benefits of pink Himalayan salt lamps are so easily debunked by science, but to be honest, I was expecting it. I look at salt lamps as beautiful decorative items for the home – they’re not medical devices and haven’t been proven to cure or treat any health condition.
There are so many people online reporting anecdotal stories about miracle cures from these products. Perhaps science has some catching up to do or perhaps the placebo effect is doing wonders. I keep an open mind and will probably end up buying one anyway.