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In part 1 I explained about nomenclatures and the most used actives in Asia to treat different problems. In part 2 we’ll learn how to build the routine itself. Remembering that most of the information here is just my opinion, feel free to debate.

What do I need to get started?

Cleansing Oil/Balm/Cream to remove oil-based substances from your skin such as heavy makeup, silicones, sunscreen waste.

to remove oil-based substances from your skin such as heavy makeup, silicones, sunscreen waste. Water-based cleanser (Foam, Cleansing Water, Gel) to complete cleaning, removing water-based substances such as old skin cells, perspiration, micro-dust.

(Foam, Cleansing Water, Gel) to complete cleaning, removing water-based substances such as old skin cells, perspiration, micro-dust. Hydration is one of the most important steps. There is no healthy and beautiful skin without hydration. Hydration can be achieved through FTE, Toner, Essence/Serum.

is one of the most important steps. There is no healthy and beautiful skin without hydration. Hydration can be achieved through FTE, Toner, Essence/Serum. Sunscreen doesn’t need to be quoted, right? In addition to protecting the skin from hyperpigmentation, the sunscreen also protects your collagen, keeping your skin younger for a longer time. It’s the best anti-aging out there.

So far so good? These are the items that you will need to start a skin care routine with Asian products. With these steps, you will be cleansing, moisturizing, and be protecting the skin.

What is unnecessary to start with?

Masks in general (Sheet Mask, Modeling Mask, Clay Mask), exfoliators with granules (can be done at home with corn powder + Cleansing Oil), Face Mist, Eye Patches… These you can add later.

Choosing the Products

Double attention when choosing the water-based cleanser

When choosing a water-based cleanser (Cleansing Water, Foam, Cleansing Gel) you should pay attention to two super important points.

The pH of the formula;

The surfactants used in the formula.

I’ll start by explaining the importance of the pH of the product. This point is very important because we must maintain the skin at a pH close to 5.5. Remembering that acid pH is below 7, neutral pH is equal to 7, alkaline pH is above 7.

Stratum corneum and enzymes

The formation of the stratum corneum, specifically the generation of its lipophilic components, involves several pH dependent enzymes. Two major lipid processing enzymes, β-glucocerebrosidase, and acid sphingomyelinase have optimum pH of 5.6 and 4.5, respectively. Both are involved in the synthesis of ceramides. Studies have shown that pH elevations in normal skin create a disturbed barrier, linked to increased activity of serine proteases* and reduced activities of ceramide-generating enzymes. As pH increases, these serine proteases are activated, while the enzymes responsible for generating ceramides, which work best at acid pH, are inactivated and compromise the structure and function of the stratum corneum.

*Enzymes that cleave peptide bonds in proteins, in which one of the amino acids in the active site is serine.

Antimicrobial properties

Skin microflora consists of transient, resident-temporary, and resident-permanent species, including coagulase-negative staphylococci. Normal plant growth is optimized at acidic pH, while pathogenic bacteria such as S. aureus thrive at neutral pH levels (pH 7). Dermicidin, an antimicrobial peptide found in sweat, demonstrates antimicrobial activity against a variety of pathogenic microorganisms. Incubation of S. aureus with a sweat fraction containing Dermidine induced >90% bactericidal effect when buffered at a pH of 5.5 and only 60% when buffered at a pH of 6.5, that is, the pH is actually very important.

Diseases

Several dermatoses are related to the unregulated pH of the skin. I’ll mention two.

Atopic dermatitis: In a study of 100 children with AD (atopic dermatitis), pH was observed to be significantly higher in the eczematous skin compared to the skin of 21 healthy children. Why is the pH altered in the atopic skin? Several factors were proposed. Free amino acids and urocanic acid, believed to be involved in creating the acidic environment of the stratum corneum, are markedly reduced in atopic skin. Filaggrin, a protein deficient in atopic dermatitis, serves as an important precursor of free amino acids and urocanic acid. Sweat secretions, which are rich in lactic acid, which may also help maintain an acid mantle, are reduced in atopic dermatitis.

In a study of 100 children with AD (atopic dermatitis), pH was observed to be significantly higher in the eczematous skin compared to the skin of 21 healthy children. Why is the pH altered in the atopic skin? Several factors were proposed. Free amino acids and urocanic acid, believed to be involved in creating the acidic environment of the stratum corneum, are markedly reduced in atopic skin. Filaggrin, a protein deficient in atopic dermatitis, serves as an important precursor of free amino acids and urocanic acid. Sweat secretions, which are rich in lactic acid, which may also help maintain an acid mantle, are reduced in atopic dermatitis. Acne: In vitro, P. acnes grows well at pH values between 6 and 6.5 and growth is greatly reduced at pH values lower than 6. In a study of acne-prone patients, the number of facial inflammatory lesions was compared in subjects using a standard alkaline soap versus those using an acid syndet bar (pH <7). The number of inflammatory lesions increased in the alkaline soap group (pH >7) and decreased in the group using syndet* acid soap at statistically significant levels up to the 4th week of application.

*Cleaners with non-soap based surfactants.

How to know the pH of a cleanser?

Using a pH meter, a tape to measure the pH of the product, or asking the company what the pH of the product is. As we have a wonderful community on Reddit (Asian Beauty), people have made a list with over 500 facial cleansers. This is the link. It will help you when choosing the cleanser. Remember that an ideal pH is between 4 and 6.

Now I’ll explain about surfactants.

Attention to the surfactants

The surfactants in cleansing products solubilize hydrophobic materials in the aqueous phase and allow their subsequent removal from the surface of the skin. The amphiphilic structure of the surfactants, consisting of a hydrophilic polar head group and a nonpolar lipophilic tail, conducts surfactants at the oil/water interfaces to facilitate cleansing. It is known that aggressive surfactants in cleansers can cause damage to skin proteins and lipids, leading to that “tight” sensation after washing, dryness, barrier damage, irritation, and even itching.

The most commonly used aggressive surfactants

Sodium Lauryl Sulfate, Sodium Laureth Sulfate, Sodium Dodecyl Sulfate, Sodium Myreth Sulfate, Sodium C14-16 Olefin Sulfonate, Sodium Alkylbenzene Sulfonate, Sodium Coco Sulfate, Ammonium/Sodium Xylene Sulfonate, Ammonium Lauryl Sulfate, TEA Lauryl Sulfate, TEA-Dodecylbenzene Sulfonate.

The first three are the most commonly used in face products. The rest is seen mainly in shampoos, but they may also come in face/body cleansers.

The least aggressive surfactants

Cocoamidopropul Betaine, PEG-7 Glyceryl Cocoate, Decyl Glucoside, Sodium Cocoamphoacetate, Lauryl Glucoside, Coco-glucoside, Sodium Lauryl Sulfoacetate, Sodium Cocoyl Isethionate, Sodium Cocoyl Sarcosinate, Sodium Cocoyl Glutamate, Sodium Cocoyl Glycinate, Sodium Lauryl Glucose Carboxylate, Sodium Lauroyl Methyl Isethionate, TEA-Cocoyl Glutamate.

Can you see how many mild surfactants there are? These are just a part of them. There is no need to use high pH and harsh surfactant cleanser.

You already know the importance of using a cleanser with acid pH and no aggressive surfactants, right? So let’s continue.

What to use after cleansing?

I, Rafael, am opposed to the use of acids (AHA, BHA, PHA, retinoic…) right after cleansing the skin, especially for those who have dry or dehydrated skin. The use of acids (especially the potent ones) after skin cleansing can worsen the problem of dehydration. This is personal and varies from skin to skin, obviously.

When we wash the skin, what it needs most is hydration, and we get this hydration in a very simple way that will not decrease the absorption of the products used after. How? By using FTEs, which are mostly liquid-based fermented ingredients (such as rice) that moisturize the skin deeply and tend to leave no residue. FTEs are products that can be easily used as many layers as you want, that is, you adjust how much of hydration you want. Some people use 1 layer, 2 layers, 3 layers, or more.

After this semi-hydration, we proceed to the use of “active” (vitamin C, AHA, BHA). But answer me, do you think we need a toner to readjust the pH of the skin after washing it with a cleanser whose pH is acidic? I’ll explain my point of view just below.

Do I really need a toner just to acidify the pH of my skin?

In my humble opinion, no. When the tests were done to know at which pH scale some acids work best, it has been observed that BHA works best at a pH of about 3, AHA between about 3 and 4, and ascorbic acid ideally between 2.5 and 3.5. These tests were done by applying the acid to human skin, which has a natural pH around 5. I haven’t seen any of these tests done with the use of a “pH-adjusting toner” before applying the acid. So if you use a facial cleanser with an acidic pH, there is no need to use the toner.

After washing the face with a cleanser with acidic pH, and moisturizing it with FTE, our face still remains slightly acidic, considering that most FTEs have an acidic pH. When applying the acid, what I suggest, and usually do, is divide the amount of product into two layers. The first layer will acidify the pH of the epidermis and the second layer will perform in a stronger way.

Using a toner with acidic pH will possibly make your skin irritated. Who has ever made the CosRX AHA/BHA Toner (or any low-pH toner) + some exfoliating acid combo and regretted because their skin got irritated? I’ve seen many comments.

I use a toner with acidic pH before my acid and I feel that the exfoliation is better, should I stop? No, if it’s bringing you good results, keep it

Free acid

Please, bear with me. This part might sound difficult.

To penetrate into the skin and to work properly, the hydroxy acids need to be in the free acid form. As the pH level decreases, the free acid level increases. The lower the pH level is, the greater the power of exfoliation and the greater the irritation and inflammation coming from the acid.

Does your product with a hydroxy acid have enough concentration to exfoliate (in a right pH) but it does not? I suggest checking the pH of your product, it may not have a pH low enough to perform the exfoliation. Stating that it has an acidic pH does not mean much because pH 6.9 is acidic pH and, for example, 10% glycolic acid in a pH of 6.9 won’t do anything.

Below is a table showing how much salicylic, glycolic, and lactic acid is free to exfoliate at different pH levels. This table was made by the great Michelle, from LabMuffin (go check her website out).

Remembering that the more acidic, the greater the chances of irritation and inflammation. If you want to decrease the irritation, you can either choose a product that has a good concentration of acid with a pH close to its pKa (let’s say 10% glycolic acid in a +/- 3.6 pH) or you can choose a highly concentrated acid with a not-so-acidic pH. You might ask me “Why a highly concentrated acid with a not-so-acidic pH?” because you can still get a good concentration of free acid in a not-so-acidic pH if your acid is highly concentrated, and being a not-so-acidic product means the irritation due to its acidity won’t be too much.

However, it’s very difficult to find a highly concentrated hydroxy acid OTC. For example, a 8% glycolic acid at pH 2.5 has 7.6% of free acid. If you’re looking for similar effects from a product with higher pH, you will need much more! FYI, you’d need 43% of glycolic acid at pH 4.5 so you can have the same amount of free acid that you’d have from a 8% glycolic acid at pH 2.5.

pKa

pKa implies the availability of the acid. Equal pH and pKa values mean that there is 50% free acid and 50% ionized. What does that mean? It means that if a product contains 15% glycolic acid at a pH of 3.6, there will be 7.5% of acid in the free form and 7.5% of acid in the ionized form. A portion of this 7.5% of the acid in the ionized form will at some point turn into free acid and will be absorbed by the skin.

Below there’s the pKa of some acids.

Glycolic acid +/- 3.6.

Lactic acid +/- 3.8.

Mandelic acid and malic acid +/- 3.4.

Salicylic acid +/- 3.0.

A pH lower than that means greater exfoliation and a greater chance of irritation, and a higher pH means less instantly exfoliation and less chance of irritation.

Most formulations containing exfoliating acids (AHA/BHA) at a high pH are generally time-release formulas (some are just badly formulated), which are forms where the level of ionized acid (IA) is higher. The IA gradually converts itself to free acid, which is the acid the skin absorbs, and the exfoliation type. This is why it is called “time-release“. This type of product is suitable for very sensitive skin.

Is it too much at once for your head? So do the following, when you are buying a product with hydroxy acid, try to look for its pH. Then you come back here and take a look at the pKa of the acid. Ideally, for it to have a better efficacy, the pH should be close to its respective pKa. Or you can choose a highly concentrated hydroxy acid with a not-so-acidic pH, it’ll still have a fair free acid concentration and won’t cause much irritation. Although, I still prefer a moderately concentrated acid with a pH close to its pKa as it’s very difficult to find a highly concentrated acid in cosmetics.

P.S.: I sent an e-mail to Michelle asking if she could read this part and tell me if there was anything she would change. She said: “It looks good! Here are a few changes I would suggest (they’re pretty minor and my opinion only so it’s up to you). Having pH = pKa isn’t necessarily the best situation in my opinion. For example, if you have a higher concentration of acid, you can get the same concentration of free acid at a higher pH than if you have a lower concentration of acid at a lower pH. The higher concentration acid will be more effective AND less irritating (since there’s less unnecessary irritation from low pH).”

She also said that “there’s some evidence that salicylic acid doesn’t need to be in the free acid form to exfoliate because it’s lipophilic enough to penetrate the skin when ionised, unlike AHAs, so it can work at a higher pH.”

Thank you, Michelle! =)

Which acids to use first?

It is not recommended to use AHA, BHA, and ascorbic acid together if your skin is not strong enough. However, if your skin tolerates a combination of acids and you want to do so, I suggest starting with BHA (salicylic acid) because it is a fat soluble acid. Then ascorbic acid (vitamin C) and then AHA (glycolic, mandelic, lactic, tartaric acid). I recommend taking a few minutes break between each acid because as they are drugs that work best at different pHs, this interaction can change the performance of each one (20 minutes is what works perfectly for me, but each case is different).

Interaction between ingredients

As I explained in part 1, of the most used actives, as far as I’m concerned niacinamide, and ascorbic acid can interact. This interaction doesn’t neutralize the effect of each other but can give that flushing effect. Also, retinoids shouldn’t be mixed with benzoyl peroxide.

What to use after acids?

More hydration. You can enjoy more of your FTE, or if you prefer, use some toner with glycerin, glycols, and hyaluronic acid. Remembering that after the acids, theoretically there should be no pH dependent products, then the “rule” is as follows: the product that is absorbed to a deeper level comes first. I see a lot of people using the “rule” “the most liquid product first”, but not always the most liquid product is the best absorbed (hello, Sulwhasoo Timetreasure Water). I made a chart to better aid in the order of application.

Order of application

Below there’s a chart made by me.

So it’s more or less like this: Cleansing Oil (PM only), Water-Based Cleanser (AM+PM), Wash-Off Mask/Scrub (PM ideally), FTE (AM+PM), Actives and Prescription* (PM ideally), Toner (AM+PM), Essence/Serum/Ampoule (AM+PM), Sheet Mask (PM ideally), Emulsion (AM+PM), Eye Cream (AM+PM), Spot Treatment (AM+PM), Cream (PM ideally), Sunscreen (AM), Sleeping Pack (PM).

*Wait a few minutes to apply the next product after the acid so it can perform better.

Remembering that this order will not always be this way because there is, for example, Ampoules that are lighter and absorb better than an Essence, Serum. I think it’s very important to make this order up to the acid part, where you will give a few minutes break (I give 20 minutes) between one acid and another. After the acid, whatever absorbs faster and best comes first.

Waiting time between each product

People ask me a lot about the waiting time between one product and another. What I say is: there is no rule. Only in the case of some acids (vitamin C, AHA, BHA), I would suggest waiting 20 minutes to apply next product because of the dependence on a pH of some acids. In the case of FTE, Toner, Essence, Serum, Ampoule etc., just apply the product and make the skin absorb it. It usually takes less than a minute for each product to absorb, but as the routine comes to the end, it may take a little longer. I suggest not applying the product and waiting for it to dry on the skin, gently press your fingers on the face or tap it to help absorption.

Examples of routines

I recommend starting with a few products only. Buy a Cleansing Oil, a second cleanser, a moisturizer, a Serum/Essence/Ampoule for treating a problem*, and sunscreen (5 products in total, to begin). Add the products gradually (1 every 2-3 days), because if you add all at once, and something undesirable happens, it will be more difficult to know whose fault it was.

*In part 1 I mentioned the most used actives and what they do.

For normal/dry skin: I made a very generalized routine, for normal to dry skin, with dark spots and signs of aging. In this routine, you can find hyaluronic acid, vitamin C, mandelic acid, tranexamic acid, arbutin, niacinamide, many antioxidants botanical extracts, fermented soybeans, fermented rice, aloe vera, peptides, ceramide, horse fat, and more.

Products with * are products that I have never used however by the analysis of the formula and pH, look like good ones. I’d love to make these examples with only products I’ve used but I haven’t tried many cleansers so far.

🌞 = morning routine.

🌙 = night routine.

🌞🌙 = both routines.

From left to right.

For combination/oily/acne skin: In this routine, you will find ingredients that treat oiliness, acne and dark spots. The main actives are fermented soybeans, rice bran, tea tree extract, mandelic acid, tranexamic acid, betaine salicylate, niacinamide, peptides, aloe vera, charcoal powder, arbutin, cocoa extract.

🌞 = morning routine.

🌙 = night routine.

🌞🌙 = both routines.

From left to right:

The Saem Natural Condition Pore Deep Cleansing Oil.🌙

CosRX Low pH Good Morning Gel Cleanser.* 🌞🌙

Innisfree Soybean Energy Essence (Light).🌞🌙

Neulii Tea Tree Blemish Control Serum.🌞🌙

Narüko AM+PM Total Brightening Mandelic Acid 5%.🌙

Swanicoco Bitamin C Calmdown Skintoner.🌞🌙

Sidmool Skin Returning Niaten Serum Niacinamide 10%.* 🌞🌙

Benton Cacao Moist and Mild Cream.🌙 (optional during the 🌞)

Bioré UV Perfect Face Milk.🌞

Where to buy

I buy wherever is cheaper. Testerkorea, W2Beauty*, Jolse, BBCosmetics… There are plenty of websites.

*Affiliate.

That’s it, guys. Now you are already experts! You already know that the pH of the product with exfoliating acid needs to be preferably close to its pKa, you already know that the pKa value of each acid is different and will always be the same for that acid, you already know that each product has its own pH, already know the importance of a slightly acidic pH for the skin, already know what harsh sulfates can do, already know how to apply the products, already know the order of the acids, already know which actives to choose.

If you have any doubts or compliments, leave a comment here. Don’t forget to register your email and follow me on Instagram so you don’t lose any posts. xoxo

The information above is not intended as a prescription. Consult a dermatologist.

Sources

Skin pH: from basic science to basic skin care;

Free acid calculator for exfoliants at specific pH levels;

Why does pH matter for AHAs and BHAs?