If you’re not getting great results from your skincare, I suggest that you stop blaming aging, the products, the ingredients, the salesperson at Sephora, or even that sunscreen-free weekend in Cabo. Instead, consider the fact that it might be your skin cells’ environment — or, more specifically, the pH at which your skin cells reside. Keep in mind that your skin’s pH can affect everything from the rate at which skin care ingredients are absorbed to the extent to which they penetrate the skin altogether, as has been definitively shown to be the case with vitamin C as L-ascorbic acid (Dermatologic Surgery, 2001). Factors like UV light, environmental pollution, and climate change all can affect your skin’s pH – causing dry flaky skin, inflammation or eczema.
Here’s everything you wanted to know about how pH could be negatively affecting your skincare results — and what to do about it.
How to Tell If Your Skin’s pH is Off
First off, recognize that if your skin has been changing, its pH has probably changed. For instance, if you’re saying your skin has changed due to the weather, it’s probably more like the weather has caused a pH change in your skin.
The best thing you can do to keep your skin looking its best is to maintain its naturally slightly acidic pH level.
Normal skin pH ranges from 4.5 to 6.5, which means it is always on the slightly acidic side. This acidity of the skin is termed the “acid mantle” and is maintained by sebaceous glands, sweat glands, and normal skin flora. The acid mantle provides a film of amino/lactic acids and oils that effectively protect skin from environmental factors (bacteria, pollutants) that contribute to premature aging and irritation.
The relative success or failure of your own skincare products depends on the integrity of your acid mantle, and hence pH level. The acid mantle of the skin serves many functions to the skin, one of which is killing unwanted bacteria. It has even been found that people suffering from chronic acne have a slightly higher skin pH, and that bringing it down with use of slightly acidic skincare products helps to control acne. A disruptive acid mantle will also not allow for products to absorb into the skin as well.
If this sounds a bit like revisiting AP Chemistry class, don’t fret. Keeping whatever you slather on your face in the mid-range of pH neutrality is a good move to nix the negative side effects of straying in either direction too much.
How to Determine Your Skin’s pH
A skin care product may claim to be pH balanced, but you can verify the actual pH of a product by using an at-home pH testing kit (available at most drug stores). Saliva tests will accurately indicate your body’s overall pH level.
What to Do if Your Skin’s pH is Off
If it is alkaline (or neutral), above 6.5: The stratum corneum (uppermost layer of the skin) is disrupted, damaging the barrier function of the skin, which translates into skin dryness and decreased antibacterial defense. A study has shown that using a skin cleanser that is basic – alkaline – like regular soap, can cause this kind of damage even after one use, and the effect is cumulative, meaning it gets worse with repeated use.
This basic pH will also leave your skin stripped of essential oils and lipids (Dermatology, 1997). Your skin may feel “tight” after washing. For this reason, very rarely, if ever, do I recommend using an ingredient in a formulation at a pH greater than 7.5. These effects will of course be more pronounced in people suffering from dermatitis, people who have sensitive skin, and in the elderly, as this subgroup already has some damage going on, and their skin’s ability to fight these assaults is suboptimal.
To reverse this, consider adding a cleanser with 10% salicylic acid, or a 15% or higher L-ascorbic acid serum to your skin care regimen.
If it is too acidic, below 4.5: By that same token, acidic pH is not a “be all, end all.” A low acidic pH can also cause for ingredients to be more irritating for those with sensitive skin. What’s more, ingredients like zinc oxide and titanium oxide – your mineral or physical sunscreens – have a “pH window” in which their efficacy is optimized. According to chemist Dr. Konstantinos Lahanas, Ph.D., “If the pH of zinc oxide or titanium oxide is too low (or acidic), the oxides will actually dissolve, leaving you with zero effects. So lowering the pH of mineral sunscreens is not a great idea.” That’s why you rarely see sunscreens with high concentrations of acids, like 10% glycolic acid or salicylic acid.
To reverse this, consider adding a slightly higher pH product to your skincare regimen, such as a moisturizer completely free of acids.
How Do Skincare Ingredients Affect Skin’s pH?
Let’s look at citrus extracts, for instance. Citric acid is a major component of citrus extracts and is one of the alpha hydroxy acids. It is used as a skin peel. It exfoliates the skin and help bring youth back to sun damaged and aged skin.
Citrus extracts have a pH of about 2-3, and that is quite a bit below the ideal range of 4.5-6.5. So regular use of citrus extracts by themselves (not neutralized by any other ingredients) makes them likely to cause skin irritation, sun sensitivity, and skin hyperpigmentation.
Another point to take into account when considering citrus extracts (or any other ingredient, for that matter) is their water content. YES, applying water to your skin WILL dry it out. How? These fruits are made of 80% or more water, but contain NO occlusive ingredients. So when you apply lemon juice on your skin and let it air dry, you’ll end up with even drier skin after it evaporates.
These effects are notable for about 48-72 hours, with a decreasing gradient over time. So while you can neutralize your skin’s pH back to the 4.5-6.5 range, you want to be sure that you take gradual steps. Don’t think you can neutralize skin with a pH of 7.0 back down in a day with use of a 30% AHA solution — or you might be sorry.
What Other Factors Play a Role in Skincare pH?
1- The amount of time you leave products on your skin. In general, products left on longer will become more acidic as the water in them evaporates.
2- Its concentration: a little acidity is good for the skin, but stronger acidity turns the product into a peeling agent. That’s when you need to be careful.
3- The other ingredients in the formulation: Acidic ingredients, like L-ascorbic acid, glycolic acid, and lactic acid, generally perform better at a lower pH. The lower the pH, the more exfoliating the formulation tends to be – and the deeper the ingredients tend to penetrate.
4- The chemical nature of the ingredients. As stated before, certain ingredients, like mineral sunscreens zinc or titanium oxide, can’t handle low acidic pH levels. You need a neutral pH for these to function properly, lest they dissolve in solution.
Does Race Play a Factor in Skin’s pH?
Interestingly, yes. One independent study from 1994 by Dikstein and Zlotogorski suggests that skin pH is more acidic in Caucasian skin, and is slightly more alkaline in Indian skin. However, there is a documented pH range present in the skins of all races, as resolved by fluorescence imaging in this 2002 study in the Biophysical Journal.
How Does the Food You Ingest Affect Your Skin’s pH?
According to Dr. Jeannette Graf, a dermatologist from Great Neck, NY and author of Stop Aging, Start Living: The Revolutionary 2-Week pH Diet, the pH of the food you consume and products you use affect the state of your skin. According to Dr. Graf, the skin should be kept at a pH slightly higher (more alkaline) than 7 (neutral pH) because most of the foods consumed by Americans result in acidity, including meat, sugar, alcohol, and processed foods. The foods are converted into acids in the bloodstream, and then the slightly-acidic epidermis becomes superacidic, and your complexion suffers.
Graf‘s opinion is further supported by homeopath Heather Osler, who states in this article that “80 to 90 percent of the average American’s diet contains acidifying foods.” Three servings of a healthy, alkaline food for every soft drink will help keep pH in line.
Bottom Line: So, How Do You Keep Your Skin’s pH in Balance?
Unfortunately, with increasing age, the skin’s pH becomes less acidic, and thus more susceptible to bacterial growth. This reduced acidity kills fewer bacteria than before, leaving the skin susceptible to bacterial growth and infections. The skin weakens as a result and begins developing problems with increasing age.
So it’s a great idea to get a read of your skin’s pH level regularly. If it is above 4.5-6.5, make sure you use slightly acidic products. On the other hand, if it is below 4.5-6.5, make sure you use products with a pH of about 7.0. Do not overdo it and expect overnight reversal of your skin’s pH level.