When it comes to skin care, the goal is usually healthy ‘normal’ skin. Healthy skin has a lot to do with pH levels.
What is pH?
I had to pull out my high school chemistry book for this one. First of all, a shout out to Danish biochemist Søren Peter Lauritz Sørensen who in 1909, defined pH. pH aka potential Hydrogen, is a measure of the hydrogen ion concentration of a solution, on a scale from 0 to 14. Like Switzerland, 7 represents neutrality, anything below it is acidic and anything above it is alkaline.
The further away you are from 7, the stronger the alkalinity or acidity of the solution. Solutions with a higher concentration of hydrogen ions are more acidic e.g. sulfuric acid and hydrochloric acid. Those with a lower concentration of hydrogen ions are more alkaline e.g. sodium hydroxide and potassium hydroxide.
What Role Does pH Play in Skin care?
When sweat, sebum and dead skin combine, a thin acidic film is spread across the surface of your skin. This is called the acid mantle. It has a pH between 4.5 and 5.5. If the acid mantle is maintained within that pH range, it will perform the following functions:
- Physical protection.The acid mantle is an oily film which makes your skin waterproof, reducing the amount of water that evaporates from the skin. It also makes it harder for external factors like bacteria to physically penetrate the skin.
- Neutralization. The acidity of the mantle makes it neutralize any alkaline chemicals that would cause the skin harm.
- Protection from microbes. Bacteria, fungi and viruses are warded off by the low pH of the acid mantle. The low pH of the mantle also keeps skin cells tight and flat so it’s even harder for microbes to penetrate the skin.
Basically, those with a pH on the lower end of the spectrum have healthier skin because the acidity protects their skin. If your skin usually gives you grief, then the acid mantle may be disrupted.
How can the Acid Mantle be Disrupted
- Skin conditions like eczema and harmful sun exposure. (Wear sunscreen, abeg!)
- Cleansers with a high pH(above 6) can wash away or neutralize the acid mantle. When the pH of the skin is raised above 6, skin cells will start to soften and separate, moisture loss will be enhanced and bacteria will easily penetrate the skin. The skin will be infected and damaged.
- Age. As we mature, the pH of our skin becomes alkaline and to maintain overall skin health it’s advised to use products that reduce the alkalinity.
Of course, every time we wash our skin, we remove this protective film. So it’s essential to use a low pH cleanser that will aid the restoration of the acid mantle.
Hold Up, The Acid Mantle Can be Restored?
Yes, but it takes time. The acid mantle can take 14 to 20 hours to be restored, “by which time, it’s most likely under assault again from another washing. Most people wash their hands about three times a day, on average. Single washings shift pH to the alkaline region, which can shift back to normal within a few hours.” Source: The Beauty Brains.
By now, you can see why maintaining the acid mantle is essential for “normal” skin.
So, How do you Take Care of The Acid Mantle?
- Use well formulated hydrating cleansers to wash your skin. Steer clear of alkaline detergents, toners, soaps or cleansers. Check out some cleansers here and here.
- Avoid long hot showers.
- Eat a healthy diet to keep your body well nourished and producing the right essential fatty acids.
- Wear sunscreen regularly.
- Apply occlusives e.g. petroleum jelly or non fragrant plant oils over your skin to help it heal when you disrupt the acid mantle. The occlusives will reduce the moisture loss.
Had you considered the pH of your skin before? Let me know in the comments.