Must Know Facts About Skincare pH
by Heather Smith on Dec 04, 2022
There is a lot of science (organic chemistry to be exact) underlying the pH of your skin and skincare products. Skincare pH is an important topic to have some understanding about, especially when you want to have the healthiest skin possible, while also avoiding marketing hype.
TL/DR: How to Restore Skin pH Balance Naturally
What is pH of Normal Skin
The skin is normally slightly acidic – that’s why part of your skin barrier is also called the acid mantle. Usually, healthy and intact skin barrier has a PH of around 4.7 (range averages 4.5-5.5). Having a slight acidity is thought to be important for fighting microorganisms and fungi and maintaining a healthy, waterproof barrier. The function of the acid mantle is to maintain barrier health. It works with your microbiome and other protective factors to create an environment that's balanced.
Clues your skin pH is abnormal are dry skin, breakouts, flaking, damaged barrier, worsening fine lines, and itching. You might also have excessively oily skin, especially if you're stuck in a cycle of overwashing.
How Do You Measure pH
pH is a number that quantifies the acidity or alkalinity of a liquid that contains water (aqueous solution). It is reported on the pH scale and ranges 1 (extreme acid) to 14 (extreme alkali).
No water? Not liquid? The pH is not measurable and the substance doesn’t technically have a pH. This is important to know because the chemistry of acids and bases has to do with the function of the chemical when it is in the presence of water. You don't need anything fancy, home tests might include simple litmus paper.
A great example is a solid bar of traditional soap. As a solid bar, it has no measurable pH. Traditional soaps are made by reacting fat with a strong base (lye/sodium hydroxide).
The saponification process breaks the bonds between the fatty acids and the glycerol. The fatty acid reacts with the base to form a salt and free glycerine is released. Once that solid bar of soap is wetted with water, the salt that was formed dissociates and results in re-formation of a solution with a basic pH.
Traditional soaps have a pH usually between 8-10 making them one of the worst ingredients for sensitive skin and for your acid mantle. After washing your face with a traditional soap, it will take many hours for your skin barrier to re-balance itself.
In addition to stripping away your natural oils, this creates a perfect storm for barrier damage. Since acne-causing bacteria and fungi love a pH higher than 6, this is another reason you want to stay away from alkaline soaps.
The Best pH For Skincare
Using pH balanced skincare products is an excellent way to improve your skin's health. In fact, this type of skincare can also help you to prevent acne, eczema and bacterial infections. These conditions are caused by altered pH levels in your skin.
When your skin's pH gets out of balance, you'll notice increased redness, irritation and inflammation. Additionally, your skin's barrier function will be impaired, which means that pathogenic microbes can enter your skin, causing infections.
The reason ‘pH balanced’ products affect your skin pH is primarily because they prevents damage caused by using products outside the normal range of the skin. A chemical peel will never be pH damaged, because the point is to damage your skin (in a controlled fashion) using an acid.
Beauty product manufacturers can balance the pH of their products by adjusting them after testing the pH of the product. Note: this is only possible with products that contain water.
Abnormal pH levels in your skin can cause acne, eczema, and fungal infections. This is because they are able to break down the acid mantle, which is a protective layer on the surface of your skin. The acid mantle is made up of lipids from your oil glands. These lipids are vital in protecting your skin from external assaults.
High pH levels also make your skin more susceptible to dryness and dehydration. This can cause premature aging and eczema. In addition, products with high pH levels are also more likely to cause irritation and breakouts. The pH of your skin should always be in the range of 5.5 to 4.5 to avoid these problems.
It's also important to avoid harsh soaps and cleansers. These cleansing agents can strip your skin of its natural oils, causing it to become overly dry. Likewise, high pH soaps can disrupt your acid mantle, which can cause inflammation and irritation. If your skin is sensitive, you can also use lukewarm water to wash your face.
Finally, it's important to make sure that your face toner closely resembles your skin's natural pH. Your toner should contain ingredients that are anti-aging, hydrating and antioxidant rich. Some of the ingredients you can look for are hyaluronic acid, Vitamin C, Vitamin E and niacinamide. Both witch hazel and apple cider vinegar are natural remedies for acne and can be used in DIY toners at home.
pH is Another Reason We Love Face Oils
As we’ve already explained, waterless products don’t have a pH. When it comes to oils, they may or may not exhibit polarity which may make them more or less likely to act as a very weak acid when in the presence of water via an emulsification system.
However, the more important feature of oils in relation to face care, is the fact they resemble (or, as in the case of something like squalane) directly mimic the natural oils and fatty acids needed by your skin barrier. Using facial oils is an amazing way to buff up the health of your skin barrier and replace some of the fatty acids that are stripped away during the cleansing process. They also help active ingredients penetrate.
Remember that, although called fatty acids, the triglycerides in our skincare to not generally function as acids at the level of our stratum corneum.
So what do you do if you're travelling and use the hotel bar soap on your face?
Get a thin layer of oil on to protect it.
Hopefully you travel with a facial oil, but if not, call room service and see what they've got in the kitchen. The best options would be grapeseed, safflower, and hempseed oils - all unlikely to clog pores (make sure none say 'high oleic.' 'High Linoleic' is great if you see those words used on the bottle).
Prakash C, Bhargava P, Tiwari S, Majumdar B, Bhargava RK. Skin Surface pH in Acne Vulgaris: Insights from an Observational Study and Review of the Literature. J Clin Aesthet Dermatol. 2017 Jul;10(7):33-39.
Blaak J, Staib P. The Relation of pH and Skin Cleansing. Curr Probl Dermatol. 2018;54:132-142.
Ali SM, Yosipovitch G. Skin pH: from basic science to basic skin care. Acta Derm Venereol. 2013 May;93(3):261-7.
Lambers H, Piessens S, Bloem A, Pronk H, Finkel P. Natural skin surface pH is on average below 5, which is beneficial for its resident flora. Int J Cosmet Sci. 2006 Oct;28(5):359-70.
Proksch E. pH in nature, humans and skin. J Dermatol. 2018 Sep;45(9):1044-1052.
Soltanizadeh N, Mousavinejad MS. The effects of Aloe vera (Aloe barbadensis) coating on the quality of shrimp during cold storage. J Food Sci Technol. 2015 Oct;52(10):6647-54.
Kuo SH, Shen CJ, Shen CF, Cheng CM. Role of pH Value in Clinically Relevant Diagnosis. Diagnostics (Basel). 2020 Feb 16;10(2):107.