Your skin is more complex than you may realize — consider how easy it is for a breakout to come on if you touch your face, or for your skin to get irritated if you add a new product into your routine, or for the weather to make your face dry. There's a science behind skin care — a lot of it, actually. Do you remember learning about pH levels in high school science class? It applies to more than just experiments; keeping your skin's natural pH level in check is important for maintaining healthy and happy skin.
In terms of beauty, pH — otherwise known as potential hydrogen — refers to the acidity of your skin. The pH scale ranges from 0 to 14, with 7 being neutral. On average, skin is around a 5. "The key concept here is the importance of the skin barrier function, which is influenced by pH, as well as other factors," said Hadley C. King, MD, FAAD. Your skin barrier acts as a shield for your skin and keeps moisture in and bacteria out. As you probably guessed, when your skin barrier function is disrupted or the pH is thrown off, it can leave to skin problems like irritation and breakouts.
Factors That Affect Your Skin's Natural pH Level
"The outermost protective layer of the skin is referred to as the acid mantle," said Dr. King. "The acid mantle is made up of sebum (free fatty acids), which mixes with lactic and amino acids from sweat to create the skin's pH."
A lot of factors can influence the barrier function of the skin. "The microbiota on the skin play an important role in the barrier function," said Dr. King. "The microbes on the skin impact the way it looks and feels, and its ability to serve as a barrier between your body and the outside world." Healthy microbiomes can fight against external and environmental factors, as well as keep inflammation in check and promote healthy skin healing.
In addition to microbiomes, sweat, oil, and skin-care products can all disrupt your skin's pH level. If your skin is imbalanced, it can feel and look dry and irritated. "Alkaline products strip away natural oils and disrupt the skin barrier, increasing transepidermal water loss," said Dr. King. To negate this issue, Dr. King recommended using gentle cleansers and moisturizers and limiting potentially irritating active ingredients.
"At the opposite side of the pH spectrum, products that are overly acidic can also be problematic," Dr. King said. "They can over-strip natural oils, which can temporarily disrupt the lipid barrier." This is why you should be careful when using acids like alpha hydroxy, retinoic, beta hydroxy, and amino fruit — they can weaken the skin's natural defenses if overused.
How to Keep Your Skin's pH Level Balanced
If you suspect your skin barrier function is compromised, Dr. King recommended using humectants like glycerin and hyaluronic acid to hydrate and barrier restoring lipids like ceramides and petrolatum to lock in moisture and restore the barrier. "Soothing agents to reduce skin irritation and inflammation can also be helpful, such as sea whip extract," said Dr. King. "Products that support healthy and diverse skin microbiota are also beneficial to the skin barrier."
When stocking your skin-care routine, she recommended sticking to gentle moisturizers, like the GoodJanes H2O My God Water Cream that don't contain actives like alpha or beta hydroxy acids or fruit acids or retinol — leave those to your serums and topical treatments to ensure you don't overdo it.