I was so wrong about many of the assumptions of my youth (and some that followed in adulthood :-)), and it turns out that this assumption about proper skin care was also not quite true. Hand soap, as well as dish soap and many other surfactant foaming cleansing agents, are alkaline solutions which, when mixed with water, work wonders for lifting oily messes from greasy pots and pans. This is a wonderful thing when it comes to dirty pots and pans, but what about our delicate facial skin? Do we want to lift all of the oils from our skin? Heck No!
The skins acid mantle
To answer this question properly, we have to talk about the acid mantle – a part of the landscape of your body that you may have never heard of, but is doing a very important job for you right this minute. The acid mantle is a thin layer of oil secreted by the sebaceous glands that sits on the surface of the skin. It has a pH of around 4.5 to 5.5 meaning it is slightly acidic on the pH scale. This thin layer of acidic oil prevents the growth of harmful bacteria and pathogens by creating an environment in which harmful bacteria cannot proliferate. It also prevents water loss, keeping skin hydrated, and is important to the enzymatic function of the skin.
Why the pH of your face cleanser is important
The typical pH of most supermarket branded cleansers range from 9-10, so they are very basic, but your skin prefers an acidic pH around 5.5. Already, this is weakening the strength of your skin barrier, but a low pH encourages the growth of bad bacteria. For example, the strain of bacteria known to cause acne (propionibacterium acnes), thrives in a high pH environment. For instance, using soaps and surfactant cleansers could be contributing to or even worsening your acne. Not only have you just washed off all the good bacteria, but now you might encourage bad bacteria. Who typically thriving on your high pH skin environment and there is no good bacteria to crowd them out or prevent them from over-reproducing.
Numerous studies such as this one, are in agreement that there is a strong correlation between pH and good skin bacteria and healthy skin. Not only are you damaging the protective layer of the skin by removing too much of your body’s natural oils. Most importantl the skin barrier is what holds your skin cells in the proper arrangement to create an effective barrier. Imagine a brick building where the bricks are your skin cells and the mortar in between the bricks are your body’s natural oils. Now imagine the mortar crumbling away due to wear and tear and the bricks becoming uneven. That is how surfactant and highly ph cleansers are affecting your skin barrier when too much of your natural oils are being stripped away.
The worse part is that they can change the Skin PH, for quite some time after using them, making it difficult for your skin to repair itself. When the skin surface is too alkaline – as after washing with cleansers, the skin gets dry and sensitive. In turn, this can lead to fine lines and wrinkles, dullness, and even eczema sooner because your skin is having trouble staying hydrated.