Thursday, April 22, 2010

Surfactants: What causes skin tightness after washing?

We all know the feeling - our skin feels tight and smooth after cleansing - but this isn't a good thing. Skin tightness is associated with a marked decrease in the water content of our stratum corneum, and can be the first sign that repeated use of this product could lead to scaling, flaking, and possible redness, which is to say irritation. So what causes this?

It was previously thought that removing lipids from our skin caused this feeling, but it's been shown that although removing too much oil is associated with and can enhance the feeling of tightness, it's not an essential component.

What has been shown to be an essential component of skin tightness is the amount of surfactant left on your skin after washing. Some surfactants don't rinse off well and leave a film on your skin. The worst culprits for this are the alkyl sulfates (like sodium lauryl sulfate or SLS) and the alkyl benzene sulfonates (also known as the alkyl aryl sulfonates like linear alkylbenzene sulfonate, which are mostly used in household cleaning products).

What can we do to reduce this feeling? We can make sure we use surfactants that rinse off well - and all but the two mentioned above do this - and we can add cationic and non-ionic ingredients to mitigate the feeling. In essence, we can incorporate mildness into our products (which was the topic for yesterday's post).

You can also use a toner on your face after cleansing to remove more surfactant (and you know I have a ton of recipes for that particular product!) or you can use fewer surfactants or only a titch of cleanser when you're washing your face! That's one of the reason I like the foamer bottle. One squirt is more than enough for some serious cleansing. If you package your facial cleanser in a pump, it makes it easy to get just the right amount for that day's face washing! 


Jelena said...

"Some surfactants don't rinse off well and leave a film on your skin."
Thanks for the information, Swift! Where can I learn more about it?

Susan Barclay-Nichols said...

I mention two surfactants in this post - those are the ones from the surfactants I've written about in the last few weeks. The rest either rinse of well or leave behind a conditioned feel.

kontakt said...

So that's the point of toners? I always wondered.

Judy said...

Indeed, where can we read the research about both surfactants leaving films, and removal of lipids not being essential to that feeling of tightness? I'd love to read more about both.