To say that the beauty business is prone to fashions and fads is a bit of an understatement. Andy Warhol said that in the future everybody will be famous for fifteen minutes.
I think it is just as true to say that everything will be the next big cosmetic ingredient for fifteen minutes. Dead Sea salts had their moment in the sun back in the early nineties. Being a natural born cynic I have a feeling that a PR campaign funded by the Israeli government may have been behind that. But for a while there were a lot of articles around on them and a fair few products based on them.
They are no longer in the limelight, but Dead Sea Salts haven’t actually gone away and I know of a couple of products based on them that continue to sell well. They also pop up in formulations where they don’t obviously fit into the marketing story and where no particular song and dance is made about their presence. Dead Sea salts are not cheap, so formulators must have some reason for continuing to use them even though they are no longer trendy.
So do Dead Sea salts actually confer any benefits or are they simply there to make a product sound natural? I thought it would be interesting to have a look at what actual data, as opposed to marketing hype, there is out there.
First off, lets have a look at the chemistry. How do salts from the Dead Sea compare to sea salt? The main difference is that the Dead Sea is rich in magnesium and calcium, so the salt crystals from the Dead Sea have a very high concentration of magnesium chloride and calcium chloride. Ordinary sea salt is largely sodium chloride. But does this difference do you any good?
There is no shortage of claims for the benefits. A quick trawl on the Internet will throw up a whole lot of suggestions for the good that Dead Sea salts will do – but there are lots of things you can say that about. Is there any real evidence? One study looks promising. A paper in the International Journal of Dermatology reports a study where bathing in 5% Dead Sea salt solution improved skin hydration compared to the same treatment using tap water. Interestingly, the improvement was mainly in subjects who had drier skin to begin with. In other words, the more that was wrong in the first place the more benefit.
One interpretation of this is that the salts were in some way improving barrier function, and the worse the barrier function the bigger the improvement. Normal skin in good condition has a pretty effective barrier function, so normalising dry skin is a big benefit. The authors speculate that the agent is the magnesium. There have been studies showing that magnesium can improve the skin’s barrier function so this sounds plausible. There is even a proposed mechanism. Denda has shown that magnesium promotes the production of ceramide, one of the key components of the skin’s barrier.
So it all ties together quite nicely. We have clinical evidence coupled with background work explaining how it could work. But science is a hard school. Although there is a pretty reasonable amount of anecdotal evidence to support this hard data, that weighs very lightly in the balance. I haven’t been able to find much direct confirmation of this rather nice story. There is a trial with 12 patients that claims beneficial results, but without a control. The lack of a control makes it very weak evidence. You have to say that the evidence is promising but not conclusive.
But as this is a blog post not a scientific paper I am going to throw a couple of my own speculations in. There is the case of Head and Shoulders. Nobody really knows how it works. The active ingredient is a zinc salt. Zinc and magnesium are not all that similar, but they do share the fact that they are metals with two positive charges. Although we usually think of Head and Shoulders as countering dandruff, another way of looking at it is that is normalising the behaviour of a bit of the skin. So we have two examples of a metal with a double charge having skin benefits. And I can add a third. Some years ago I developed an anti-fungal shampoo. The logic was to kill off the yeast that caused dandruff. It worked very well in the clinic and has gone on to be a great success around the world. What we didn’t know when we started but found out while we were working with it, was that it bound very strongly to iron. In fact it did so strongly that we had to stop using metal stirrers because it pulled the iron out of them and made them go rusty. The significance? Iron is usually a double charged metal as well. Could the zinc in Head and Shoulders and the magnesium in Dead Sea salts be displacing iron? And my supposed anti-fungal agent could be binding to the iron in the skin too. One last straw in this idea. A rather curious paper appeared in the Journal of Investigative Dermatology in 2001. Some Estonian workers found that iron levels in the skin of people suffering from dermatitis had levels of iron 4 times higher than normal.
What does it all mean? I can’t honestly say I know, other than the levels of metals in the skin may, just may, affect the way the skin handles its moisture balance. One easy and relatively cheap way of affecting the metal balance in the skin is a bath in Dead Sea salt. If your skin is a bit on the dry side you could give it a try. It might just do the trick.
Declaration of interest – my friends at Artful Teasing sell Dead Sea Salt blended with essential oils. Thanks to them for the image. I am not actually on a commission but I like to see them do well.
Journal of Investigative Dermatology (2001) 116, 886–890; Patients with Allergic and Irritant Contact Dermatitis are Characterized by Striking Change of Iron and Oxidized Glutathione Status in Nonlesional Area of the Skin
Sirje Kaur, Mihkel Zilmer*, Maigi Eisen, Tiiu Kullisaar*, Aune Rehema* and Tiiu Vihalemm*
International Journal of Dermatology. 44(2):151-157, February 2005. Bathing in a magnesium-rich Dead Sea salt solution improves skin barrier function, enhances skin hydration, and reduces inflammation in atopic dry skin. Proksch, Ehrhardt MD, PhD; Nissen, Hans-Peter PhD; Bremgartner, Markus MD; Urquhart, Colin PhD
Archives of Dermatological Research Volume 291, Number 10, 560-563, Some magnesium salts and a mixture of magnesium and calcium salts accelerate skin barrier recovery M. Denda, C. Katagiri, T. Hirao, N. Maruyama and M. Takahashi
Advanced Drug Delivery Reviews Volume 54, Supplement 1, 1 November 2002, Pages S123-S130 New strategies to improve skin barrier homeostasis Mitsuhiro Denda
Isr Med Assoc J. 2001 Nov;3(11):828-32.The role of trace elements in psoriatic patients undergoing balneotherapy with Dead Sea bath salt Halevy S, Giryes H, Friger M, Grossman N, Karpas Z, Sarov B, Sukenik S.