With the exception of one recent breakout (which was the result of excessively sweating in the hot, humid, unforgiving, North Carolina sun), I’ve been entirely acne free for going on 5 months. Not only that, but my formerly very reactive skin has massively decreased in sensitivity. I’m ecstatic about the changes, but it took me a long time to get here. I’m actually a little frustrated with myself because it didn’t have to take so long. The solution was in front of me the whole time, but it wasn’t until 6 months ago that I truly recognized it. I just made a single change to how I thought about my skincare product selection, which I directly credit with the elimination of my chronic, hormonal breakouts and sensitive skin: I started really caring about my moisture barrier.

It’s not that I didn’t care about my moisture barrier before. I just didn’t think about actively nurturing it. The only time I consciously considered my moisture barrier was if it had been disrupted and needed repair. Otherwise, I only acknowledged it by making passive efforts to avoid injuring it. This, it turns out, wasn’t enough. The realization I had was that I needed to vigorously and strategically strengthen that layer of my skin, so that’s what I set about doing. I’m going to talk about what I did and why it worked, but first, let’s talk a little bit about what the moisture barrier is and why it’s so important.

What is the Moisture Barrier?

The epidermis, which is the visible part of our skin, is comprised of multiple layers, with the outermost layer being the stratum corneum. The stratum corneum is the protective layer, and what we also know as the “moisture barrier” or “lipid barrier.” It’s comprised of dead, flattened cells called keratinocytes, which are continuously shed and replaced by newer keratinocytes, and held together by fatty acids, ceramides, and other lipids. Together, the lipids and keratinocytes act as a waterproof barrier that effectively keeps water in the skin and prevents bacteria, irritants, allergens, and other microorganisms from permeating it. The lipids also play a key role in encouraging new cell proliferation in the deeper layers of the epidermis.

When our moisture barrier is compromised, our skin is left unprotected and we begin experiencing trans epidermal water loss (TEWL). This leaves our skin susceptible to dryness, irritation, stinging, redness, sensitivity, and acne. Additionally, moisture barrier damage can also cause an increase in sebum production as the body tries to repair what’s been done. If you’ve ever had skin that’s somehow simultaneously dry and oily (often referred to as “dehydrated-oily skin”), that’s the result of a weakened moisture barrier struggling to correct itself. The most common cause of a damaged moisture barrier is over exfoliation (either manually or chemically), but it can also be a result of sunburn, over cleansing, or using skincare products with a pH that’s too high/alkaline. The pH detail is important, and I’ll talk more about that in just a minute.

The good news is that moisture barrier damage is not irreparable, though repairing it does take time. It can take anywhere from a couple of weeks to a couple of months, depending on the severity of the damage. However, there are active steps that can be taken to assist with the repair process. Remember how the moisture barrier is held together by all those fatty acids and ceramides? Our skin is actually able to effectively make use of topically applied essential fatty acids, such as oleic acid and linoleic acid. Essential fatty acids are found in abundance in many plant based oils, including argan, rose hip, baobob, passionfruit seed, olive, jojoba, and literally hundreds more.

How I Changed my Routine:

In the same way that topically applying oils high in essential fatty acids assist with repairing a damaged barrier, they are also very useful for strengthening a perfectly healthy moisture barrier. I’ve been a champion of face oils for a long time and have used them myself for years, so I didn’t actually have to change much about my routine in regards to essential fatty acids. However, stopping to think about why they work so well has greatly increased my appreciation for what these oils are doing for me on a daily basis, and has made me more aware of how varying levels of oleic and linoleic acids in individual plant oils work with my skin.

For face oils, most plant based oils will work, though oils higher in linoleic acid such as passionfruit seed oil tend to have a better success rate with acne prone skin. A very small sampling of some of my favorite oils includes:

• Shea Terra Organics 100% Organic Moroccan Argan Oil ($24)

• Sunday Riley Juno Hydroactive Cellular Face Oil ($125)

• Tarte Maracuja Oil ($46)

• Shea Terra Organics 100% Pure African Baobob Oil ($18)

It’s worth noting that there’s no need to worry about pH where oils are concerned. Only materials and solutions containing water have a pH, so plant oils are neither acid nor alkaline. EDIT 06/01/2014: Plant oils do have a pH, but it’s not easily measurable using a pH strip since the strips can only measure the acidity/alkalinity of aqueous solutions. I’ll be updating with more information about this when I know of a way oil pH can easily be measured at home.

Sources:

The regulation and role of epidermal lipid synthesis

Advances in Lipid Research, 1991

Barrier function regulates epidermal lipid and DNA synthesis

British Journal of Dermatology, 1993

What is the Acid Mantle?

I think most of us have at least a vague awareness of the importance of pH when it comes to skin health. I talk about pH a lot in my product reviews, but I’m usually referring to an optimal pH for a particular product or ingredient to work effectively. In addition to product efficacy, the actual pH of our skin has a lot of relevance in the overall health of our epidermis.

The outermost layers of our stratum corneum/moisture barrier have an acidic pH that can range from 4.0-6.0, with the average being 4.7. The acidic layers are often referred to as the “acid mantle,” which plays an extremely important role in the condition of our skin. The acid mantle’s low pH serves to stop the growth of harmful bacteria, fungi, parasites, and other pathogens, as well as maintain the durability and structural integrity of the keratin proteins in our keratinocytes. Those with a pH on the lower end of the 4.0-6.0 scale have greater overall skin health.

When we use products with a high/alkaline pH, we are disrupting our acid mantle. Alkaline products cause the keratin proteins to soften, and as they lose their structure, they also lose their protective qualities. When our acid mantle is disrupted, our skin becomes prone to infection, acne, roughness, flaking, irritation, and dehydration. Once the acid mantle has been compromised, it takes somewhere between 14 and 20 hours for the pH to return to normal, assuming you’re vigilant about the pH of your skincare products throughout the healing process. During that time, your skin is more vulnerable to pathogens.

This disruption happens most commonly as a result of using the wrong facial cleanser, as most bar soaps and foaming facial cleansers have a pH of 8.0 or higher. I’ve also seen an alarming number of Pinterest posts over the past year encouraging the use of baking soda as a facial scrub, and I die a little inside every time I see one. The problem with baking soda is that many people don’t see the immediate harm to their skin, so they think it’s fine to keep using it. This thinking is flawed, because even if they don’t see immediate injury, there is cumulative damage that results from the frequent use of such a highly alkaline product. Continued use of baking soda as a facial scrub can permanently raise your skin’s pH to a 6.0 or higher, leaving the skin open to dryness, infection, and damage on a perpetual basis. It’s a bit like smoking in that way – people don’t die because they smoked one cigarette, or a pack of cigarettes, or even several packs. But if they keep on smoking, chances are good they’re going to wake up one day with cancer, emphysema, or heart disease.

How I Changed my Routine:

Even though I’ve never used baking soda on my face, I have been guilty of breaking the pH rule. I have a huge weakness for the rich texture and lather of a creamy, foaming, facial cleanser, so I’ve looked the other way when it came to the high pH. I didn’t realize it at the time, but I was paying for it in acne and sensitivity. Eliminating cleansers with a pH of 6 or higher from my skincare universe had a very marked impact on the frequency of my acne. My breakout occurrences decreased tremendously when I became more vigilant about the pH of my cleansers (I aim for 5.5), and none of my breakouts since banning those high pH cleanser were of the cystic variety. I was able to keep one of my old favorites (Cerave Foaming Cleanser) in rotation, but I also had the added joy of discovering 4 new cleansers that I like even more than any of my old cleansers:

• Su:m37 Miracle Rose Cleansing Stick (pH 5.5 | $26)

• FutureDerm Skin Reborn Facial Cleanser 8.31 (pH 5.0 | $39)

• Sunday Riley Ceramic Slip Cleanser (pH 5.0 | $45)

• Biologique Recherche Lait U Cleansing Milk (pH 4.5 | $26)

• Cerave Foaming Facial Cleanser (pH 5.5 | $10)

In addition to switching cleansers, I also added in a dedicated daily acid treatment in the form of an acid toner. I’m currently extremely loyal to Biologique Recherche Lotion P50 (the phenol-free formula) because it has the lowest pH of any of the others I’ve tried, as well as the most visible impact on my overall skin texture, but there are other acid toner options available at lower price points:

• Biologique Recherche Lotion P50 (pH 3.0 | $59)

• Silk Naturals 8% AHA Toner (pH 4.0 | $9)

• Pixi Glow Tonic Beauty Elixir (pH 4.0 | $29)

Sources:

Natural skin surface pH is on average below 5, which is beneficial for its resident flora

International Journal of Cosmetic Science, 2006

The Concept of the Acid Mantle of the Skin: Its Relevance for the Choice of Skin Cleansers

Dermatology, 1995

Nurturing the Moisture Barrier / Stratum Corneum

It took about month of adherence to the changes I made to see the true impact of my skin’s overall improvement. The decrease and eventual disappearance of my acne was obviously the most visible benefit, but the massive reduction in my skin’s sensitivity was also a key aspect in the improvement of my skin’s health. Strenghtening my moisture barrier helped a lot in terms of keeping my acne away in and of itself, but so did the use of Tretinoin and BHA. The thing is, there is no way I could have used or continued to use the amount of BHA I need if my moisture barrier was in the state it was last year. I would have been far too sensitive and suffered from frequent irritation, especially when using the Tretinoin and BHA together. Because my skin is now more resilient, I’m able to treat it with the actives it needs to keep my hormonally triggered breakouts out of the picture. And when I do have breakout, such as the one I experienced just recently – it’s far less severe, and I’m able to spot treat it somewhat vigorously without worrying that I’m going to wake up with red, rough, peeling skin and an army of cystic volcanoes surrounding it.

Everyone’s skin is different, and acne happens to people in varying degrees of severity with a broad range of possible causes. A strong moisture barrier alone may not be enough to get rid of very severe acne, but it will most certainly help improve the odds, as well as make skin more resilient to some of the more intense topical treatments available.

If you’re interested in strengthening your own moisture barrier, here are my recommendations:

1. Don’t use skincare products with a pH of 6 or higher. Pay special attention to the pH of your cleanser.

2. Use an acid toner or a daily acid treatment (2%-8% at a pH of 3.0-4.0).

3. Incorporate plant oils containing essential fatty acids into your routine.

4. Don’t over exfoliate, over cleanse, or put yourself at risk for sunburn.

Also, now that you know all of this, don’t be surprised if you find yourself looking at somebody’s clear, dewy skin and thinking, “That is one fantastically functioning moisture barrier! How does she do it?” I experience this at least twice a day.

EDIT May 26, 2014: I’m getting lots of questions about where to buy pH strips! You can find pH strips at almost any store that sells fish tanks, many drug stores, and big box stores such as Wal-Mart. You can also find them on Amazon. All pH strips are not created equal – some strips are more accurate and consistent than others. I’ve tried a few brands, and so far these are the best I’ve tried:

SEOH 0-14 pH Indicator Strip ($11 + $5 shipping) – available on Amazon.

Be sure to store your strips in a dry place – any exposure to moisture before using can damage them.