I am reposting a part of reply I just wrote to a comment, since not everyone reads the comments (and I tend not to even read what comes in frequently, because of all the spam).  It covers the issue of myths about dry skin, from my perspective:

With eczema, dryness is almost a separate issue. You won’t hear that from anyone else, because the accepted view is that dryness causes the eczema, which I have found in my experience of actually eliminating eczema is not the case. I say “almost”, because dryness is a modulator that can make people more susceptible with lower levels of detergent exposure, as described on the site. I hear (more than I care to think about) from SolveEczema.org users who use products I find unacceptably drying, who are nevertheless happy because they get rid of the eczema.

   I’m going to write more about the dryness issue in my book – which, thanks to the crowdfunding, I can describe as “upcoming”! My bar soap experiments ended up bringing me to an entirely different idea about dry skin and how products cause it than I expected. Perhaps given the experience with detergent, I shouldn’t have been so surprised.

   Again, I believe dryness alone isn’t the reason for the eczema. After seriously experimenting with over a hundred different bar soaps, I also eventually came to the conclusion that dryness associated with the use of the products was not the result of stripping the skin of oils. I came up with a general rule and gave it a name (with some apologies for the presumption, but in hopes of making it more memorable):

   Lumsdaine’s Law: For most people, under most conditions, eczema and dry skin are more the result of what is left on the skin than what is stripped from the skin by washing.

   Adding too many moisturizing ingredients to soaps seems to backfire. We all think – as I thought before I did these experiments – that skin gets dry from washing because oils are removed, so adding moisturizing ingredients should help, right?  As with so many things, our assumptions trip us up.

   What I found is that immediately after washing with a “moisturizing” product, the skin feels soft – just as it feels soft right after washing with water or moisturizing with a creamy, absorbed moisturizer – but if I only used that product (which I was fastidious about doing while I tried each soap), over time, my hands became horribly dry. It happened over and over again with different “moisturizing” products, the opposite of what I expected.

    The surprise came when I got fed up with how dry my hands were from one product and just went back to my regular soap before my “trial” was over. My hands went back to normal almost immediately, far faster than could be explained by the typical view of how they became dry and how they might have normalized. I was able to repeat this with other products – which led to the lightbulb moment.

    I describe this in my talk – water, alone, a small layer of water on the skin, increases the permeability. Not enough to create eczema, but enough that if one, say, doesn’t dry the skin well enough after washing in the winter (with all the dry air), the hands chap. Increased permeability leads to water loss, leads to dry skin. I warn about absorbed, creamy (what I call “emollient”) moisturizers in my site, in part because they seem to create these same conditions. The skin feels more hydrated immediately after applying – just as it does with small amounts of water, right in the moment – but over time, the skin loses water (among other things). I think this is what is happening with very “moisturizing” soaps. (By the way, this is also why I recommend drying well, with a soap-washed towel, after a shower, NOT patting lightly and moisturizing over too much water – the opposite of the traditional recommendation.)

   I’m not saying some moisturizing ingredients aren’t good or are always going to create these conditions. One of the most lovely soaps I have ever used is the Luxo Banho Creme, which has sweet almond oil in it. But overusing moisturizing ingredients – which results in the kinds of products that make the skin/hands feel very moisturized immediately following usage, perhaps to the point that they don’t even feel clean – seems to create the conditions that lead to water loss over time and dry skin. The Luxo Banho – and every soap I have used that I consider the best – leaves the skin feeling clean and normal, not overly moisturized. On the other end of the spectrum, I think soaps can be drying if saponification is too complete and the end result may thus be far too alkaline – there’s a couple of products where I believe that may be the case – but that’s just a guess.

   Sadly, people with dry skin buy the “moisturizing” products which are in turn going to make their dryness worse, and assume it’s about their skin, not the products they are using!

Image credits: Dry land/water excerpted from freedigitalphotos.net photo by prozac1.  (I can’t seem to force WordPress to directly subtitle the photos anymore, no matter what I do, sorry!)  Soap dish by A.J. Lumsdaine.