Impact of pH on Acne

Last updated on: July 15, 2020

All right, let’s talk about acne.  As one who battled acne during my teens, finally gave in and decided to go on Accutane in my early 20s, and who still can get acne if I use the wrong skin care products, here’s what I’ve learned:

Acne is a terrible ailment. Putting things in perspective, it’s not like cancer or MS or Parkinson’s or a whole litany of other debilitating and possibly terminal diseases (and indeed, one of my good friends would remind me, it’s such a first world problem), BUT it still renders an emotional and psychological toil that can be devastating (I’m almost forty, and the emotional scars are still with me).

What didn't help my acne

-Light therapy didn’t help.

And, honestly? Light therapy? REALLY? I'm talking blue light therapy that penetrates the hair follicle. Slightly longer wavelengths than UVA, it just really doesn't seem like a good idea when we think of skin aging and hyperpigmentation spots. I guess I was just young and dumb when I thought this was a good idea. 

-Oral antibiotics didn’t help. 

Again, systemic antibiotics as a first line of treatment for acne, REALLY, ? Your intestinal flora will appreciate it if you skip this mode of "therapy", which has been shown to work in only about 10 to 20% of acne cases. My excuse - this was the '90s, we had NO idea there were good bacteria :) 

-OTC and prescription acne treatments didn’t help.

At this point, I honestly can’t remember ALL the ones I tried, but I know these were some of the actives I tried: benzoyl peroxide, salicylic acid, Retin-A. ALL of these increase photosensitivity, again, NOT a good idea for my skin's appearance in 20 years. 

-Dermatologists (including the state renowned doc) didn’t help.

I couldn't try all the above in a vacuum (aside from the OTC acne treatments). Dermatologists were the ones recommending these "therapies". 

Had I known then what I know today about Western medicine (that it is all too often used as a BandAid approach to fix symptoms of a deeper issue rather than trying to determine the root cause of the issue), then I would have given more thought to the above treatment options.

Brief clarification here: Don't get me wrong, NOTHING beats Western medicine when it is used appropriately and when it is necessary - i.e. when your gallbladder or appendix ruptures or when vaccinating against smallpox, measles, mumps, rubella or treating Ebola, BUT it could be so much more effective if doctors used a more holistic approach when treating people.

What about Accutane?

 -Accutane helped but at a cost I would NOT pay if I had it to do over again. In my early 20s, I broke down, threw in the towel, and asked for a prescription of Accutane. 

Accutane largely helped my acne, but the side effects were so severe, I didn’t complete the course (headaches, increased bile production), and I’m not entirely sure some of the health issues I’ve experienced in my 30s (extremely dry skin, gallbladder problems, allergies) aren’t at least in part (if not entirely) due to Accutane. 

It’s incredibly difficult to find solid information on side effects from Accutane, especially long-term side effects, and honestly, the damage is done now, so there’s no use crying over spent milk.  While I can’t go back in time and reverse MY decision, I can ask other people to PLEASE consider EVERY other option before choosing Accutane.

I’ve learned a ton since my 20s, and I’m going to share that knowledge with you below.

Disclaimer:  I am NOT a medical doctor.  I do not conduct dermatology studies in petri dishes or investigate enzymatic effects .  In the words of Baz Luhrmann (don’t worry, you’re ALL too young to know who I’m talking about), the rest of my advice has no basis more reliable than my own meandering experience.  So, please, take what you read here with a grain of salt, it’s only my own evidence-based experience I’m presenting below (yes, in my life, I base my faith in everything on evidence 😊).

I stopped using traditional acne products when I stopped taking Accutane.

What I learned during my personal battle with acne?

My skin looks and feels healthier when I treat it well.

My skin tends to break out more when I use alpha hydroxy acids (example: lactic acid) or beta hydroxy acids (ex. salicylic acid).

My skin can tolerate carnitine (another beta hydroxy acid) very well. I firmly believe the kitchen sink worth of products, medicines, and treatments I used in my youth to battle acne have contributed to the uneven pigmentation I have today (if you’re currently using acne treatments like benzoyl peroxide or Retin-A or any product with limonene, please, do yourself a favor, and keep your face out of the sun).

Okay, enough about my experience.  Let’s look at the big picture.

Skin Anatomy

It’s about to get technical, so please, hang with me here.  Let’s start out with a basic cartoon of the skin (Reference 1).  The epidermis is the outermost skin layer and the dermis is below it. 
The epidermis itself is composed of four skin layers as shown in the picture below (Reference 2).

Let’s go ahead and look at the lowest layer of the epidermis, the stratum basale. 

The stratum basale is composed primarily of basal keratinocyte stem cells (there are also melanocytes, which produce melanin, immune cells, and touch receptors, but by and large, the cells in the stratum basale are keratinocyte stem cells).

Let’s move up to the stratum spinosum layer.  This layer is composed mainly of keratinocyte cells and is where cornification starts.  In this layer, keratinocytes (these cells are called keratinocytes because they’re great at making a protein known as keratin (you know you’ve heard that word somewhere before, right?  Think, hair!)).

The keratin proteins contain high quantities of sulfur containing amino acids, which react with the sulfur containing amino acids in other keratin protein molecules and allow cross-linking to happen. 

Cross-linking allows these proteins to become something greater than themselves – strong, impenetrable fibers.  

At the same time that the keratinocytes are busy making keratin, cornification also starts in the stratum spinosum layer (no, cornification is not what happens to the TV when The Big Bang Theory comes on, when your goofy uncle tells a joke, or when I walk into a room 😊), cornification is the process where the keratinocyte cell begins programmed cell death… it’s nucleus starts to die, the cell starts to flatten, and the cell membrane starts to degrade.

And, as cornification continues for each keratinocyte, the cell eventually stops making keratin.  It’s then called a corneocyte (I know, right, its name keeps changing), and it keeps getting pushed closer and closer to the skin surface pushing up into the stratum granulosum layer and then the stratum lucidum layer, and finally (once the cell nucleus is completely gone and there’s essentially only the fibrous cross-linked keratin left) into the stratum corneum.

Like an onion, the stratum corneum is also composed of layers.  About 15-20 layers of corneocytes in facial skin, and about 200 layers on the palms of your hands and the soles of your feet (Reference 3).

And, one more thing about the epidermis before we finally talk about acne.  The stratum corneum does not just cover the surface.  It also lines each individual hair follicle, so cornification also happens within the hair follicle.

All right, so, what does ANY of this have to do with acne?

The Pathogenesis of Acne

Well, acne is considered to be a problem with keratinization (aka cornification).  In fact, there’s a term for it:  follicular hyperkeratinazition (this info comes from multiple references below, and sorry, I didn’t keep track here).  Keratinocytes/corneocytes are designed to push each other up and out of the way and eventually (once they reach the skin surface) to slough off. 

Well, when things go awry, the keratinocytes stick to each other too well and do NOT shed as they should.  When this happens inside the hair follicle, the excess keratinocytes can plug the pilosebaceous apparatus causing one of four things:

-Acne pustule
-Acne cyst

Reference 4

So, why won’t the keratinocytes just act normal?  Why won’t they migrate like they should, what’s going on?

Several papers demonstrate that lower pH impairs wound healing by reducing keratinocyte viability and keratinocyte/corneocyte migration (see references 5 through 7).  

Why is this? 

Well, if we look at how desquamation happens, enzymes help promote shedding (aka sloughing aka desquamation) of the corneocytes.  These enzymes perform optimally at neutral pH of 7.0 (Reference 3). 

Wait, but skin is acidic, right? 

We all know our skin has an acid mantle.  This acid mantle is a very thin film composed of free fatty acids, sweat, and normal skin flora and this film is on top of our outermost layer of corneocytes at the very top of the stratum corneum.  The pH of this acid mantle is usually reported to be between 4.5 to 5.5.

And, there are literally TONS of papers showing that the acid mantle for acne prone individuals is typically higher than for normal individuals (Reference 8).  

However, when we look up pH and acne prone skin on google instead of google scholar, we find mainstream sites state that lower pH of the acid mantle contributes to acne and inflammation and higher pH of the acid mantle contributes to dry skin (Reference 9, 10).

So, we’ve got conflicting evidence of whether raising or lowering our skin pH is desirable if we suffer from acne.

Let’s take another look at the acid mantle 


The acid mantle is a very thin surface layer sitting on top of the surface of the stratum corneum.  If we focus just on the pH of the acid mantle, we lose sight of the pH distribution throughout the rest of the stratum corneum.  

Skin Deep (Stratum Corneum)

When we start stripping layers from the stratum corneum, the skin pH increases pretty dramatically from the surface (acid mantle) of 4.5 to 5.5 in folks with normal skin to about 6.8 at the bottom layer of the stratum corneum (reference 3). 

The "normal" pH gradient of skin is either more shallow or deeper when a person has skin disorders.
It's unclear why this abnormal gradient exists... in other words, is the gradient part of the cause of the skin condition or is it simply a symptom of the skin condition?

And, what's the optimal pH for your skin?

Studies show that reducing the pH (from 6.0 to 5.0) of a wound prolongs wound healing time because it interferes with normal keratinocyte function (Ref. 7), and it's possible the same thing happens in acne comedones - the acne cyst forms because pH is too low and doesn't allow normal shedding of the keratinocytes.  It's also possible that this is part of a positive feedback loop (where acne lesions beget more acne lesions). 

This podcast episode goes a bit deeper into the link between pH and skin conditions (acne and other conditions)

Results based skincare

Meanwhile, pH is a huge consideration during product development at Rain Organica.  For all products currently offered, extensive development went into evaluating relatively minor pH shifts (about 0.5 pH units, so for example pH 5.5 versus 6.0) and testing the formulations at each pH on myself and product testers. 

Over the course of about 8 years, the optimal pH range was refined as product testers with a variety of skin conditions reported back on which worked best for their skin and ultimately landed in the range supported by the real life evidence and backed by real science for being the healthiest for your skin.

Try these products out for yourself and see what a difference intentionally formulated skincare makes for your skin's health and vitality.




3. K. Kabashima (Editor). Immunology of the Skin: Basic and Clinical Sciences in Skin Immune Responses. Chapter 2. First Edition, 2016, IX, ISBN: 978-4-431-55853-8.


5. Lönnqvist S1, Emanuelsson P2, Kratz G1,3. Influence of acidic pH on keratinocyte function and re-epithelialisation of human in vitro wounds. J Plast Surg Hand Surg. 2015;49(6):346-52. doi: 10.3109/2000656X.2015.1053397. Epub 2015 Jun 7.

6. Fluhr J, W, Elias P, M: Stratum corneum pH: Formation and Function of the ‘Acid Mantle’. Exog Dermatol 2002;1:163-175. doi: 10.1159/000066140.

7. Kruse CR1,2, Singh M1, Targosinski S1, Sinha I1, Sørensen JA2, Eriksson E3, Nuutila K1. The effect of pH on cell viability, cell migration, cell proliferation, wound closure, and wound reepithelialization: In vitro and in vivo study. Wound Repair Regen. 2017 Apr;25(2):260-269. doi: 10.1111/wrr.12526. Epub 2017 Apr 24.

8. Prakash, Chaitra et al. “Skin Surface pH in Acne Vulgaris: Insights from an Observational Study and Review of the Literature” Journal of clinical and aesthetic dermatology vol. 10,7 (2017): 33-39.







 Additional references





5. M. Thiboutot (2000) The role of follicular hyperkeratinization in acne, Journal of Dermatological Treatment, 11:2, 5-8, DOI: 10.1080/095466300750163645

6. HeikeWagneraKarl-HeinzKostkabClaus-MichaelLehraUlrich F.Schaefera. European Journal of Pharmaceutics and Biopharmaceutics. Volume 55, Issue 1, January 2003, Pages 57-65. pH profiles in human skin: influence of two in vitro test systems for drug delivery testing. rights and content

7. Frank Rippke, Volker Schreiner, Hans-Joachim Schwanitz. The Acidic Milieu of the Horny Layer. American Journal of Clinical Dermatology, 2002, Volume 3, Number 4, Page 261.

8. Chan, Aegean and Theodora Mauro. “Acidification in the epidermis and the role of secretory phospholipases” Dermato-endocrinology vol. 3,2 (2011): 84-90. doi: 10.4161/derm.3.2.15140



11. Öhman, HansVahlquist, Anders et al. The pH Gradient over the Stratum Corneum Differs in X-Linked Recessive and Autosomal Dominant Ichthyosis: A Clue to the Molecular Origin of the “Acid Skin Mantle”? Journal of Investigative Dermatology , Volume 111 , Issue 4 , 674 – 677. 12.












Brandy Searcy founder Rain Organica

About the Author

Brandy's a formulation scientist and self-proclaimed health geek who loves hiking, gardening, bird-watching, and body boarding. 

Her struggle with acne during her teens and 20s led to a holistic and healthy approach to skincare, embracing skin as an organ to be loved and cared for rather than a canvas to wage war on. 

Since 2008, she's been developing all-in-one products for a simple routine at home, & Rain Organica started when her backpacking friends asked for a portable skincare routine to keep their skin healthy & happy on and off the trails.

You can try Rain Organica for yourself with The Essentials Kit, a complete skincare routine in just 3 steps.

Brandy's LinkedIn Bio

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