You may have heard about your skin's pH, or at least remember the concept of pH from chemistry class, and the fact that it should be balanced. I remember seeing ads for a skin care lotion when I was younger that always talked about the optimal skin pH, but don't remember understanding too much about it.
So what is the pH of your skin and what does balanced mean in this context?
The pH is simply the measure of acidity or alkalinity of a water-based solution. And since water is present in our skin, we can also measure the pH of our skin. pH is measured on a scale of 0 to 14, with anything less than 7 deemed acidic and anything over 7 alkaline.
The natural and optimal pH level for our skin is somewhere around 5-6, i.e. slightly acidic, and it is at that level that most of us will experience the least issues with our skin.
Why does it matter?
has shown that people suffering from oily akin and acne typically have an elevated skin pH (on average over 6) which means that the skin's barrier function which normally keeps bacteria and dirt out has become impaired and is letting those external pollutants into the skin. These bacteria also survive very well in alkaline environments which means that once they are there, they do not die as rapidly as they would if the skin's pH were normal.
Many things contribute to the acidity of our skin including genetics (research has shown that pigmented skin is typically more acidic than white skin), sex (men tend to have slightly more acidic skin than women) or even the area on our body (skin has been found to be more alkaline in elbow creases for example).
But in addition to these, there are also a number of factors that are influenced by our behaviour.
The most important of these relates to skin care, namely cleansing of the skin. Many widely used cleansers are formulated with surfactants which are excellent at removing dirt and bacteria from the skin, but which are also alkaline by nature and therefore raise the skin's pH contributing to weakening. Research
has even shown that something as simple as washing with pure tap water (pH levels of 8-8.5 in the UK) can raise the skin's pH for up to 6 hours after washing.
How can I help my skin become more acidic?
The best way to help your skin (after all we all need to wash our face) is to either make sure your cleanser is acidic or neutral (this is not always simple as most cleansers do not report acidity on the label, but looking for cleansers that include acids in their ingredient mix is usually a good start) or to use a slightly acidic toner after washing.
One of my favourite simple toners is based on apple cider vinegar (beware the slight smell) and can be easily made at home. Simply dilute apple cider vinegar in water and use up (keeping an eye out for any bacterial growth if you are not using a preservative).
Apple Cider Vinegar Toner
½ teaspoon of apple cider vinegar
100ml of water
Mix together and apply using a spray bottle or on a cotton round.