Skin Biology

Did you know that your skin is like an onion? It has layers, and we are going to focus on the ones you need to know to understand the skincare landscape: epidermis and dermis.


Your epidermis is the top layer of the skin that you can see and touch. It is made of cells called keratinocytes. On your dermis is where most of your skincare products are going to work, so let’s see what it is inside: 
Lipid Matrix: it develops barrier functions. It keeps away outside aggressors, like UV rays or pollution, and it keeps in good things like water. It is very important for your skin health.
Hyaluronic Acid: this well-known ingredient is naturally found in your epidermis and dermis. It works to support and get water.
Natural Moisturizing Factors (NMFs): they help your skin function correctly. As the Hyaluronic Acid, they get water. We are sure you are familiar to some of them: Urea, lactic acid, 
Acid Mantle & Microbiome: they work together to make up your first line of defense against the environment.
Melanocytes: they are responsible for the pigment in your skin. And, for the freckles and hyperpigmentation.


The dermis is the second main layer of your skin. It has an important role because it has structure components responsible of skin issues such as suppleness, sagging, and even wrinkle formation. What is inside your dermis? 
Fibroblasts: they are responsible of most of skin functions, like collagen synthesis or wound healing. - Collagen & Elastin: they are structural proteins that hold your skin up. Their loss causes fine lines and wrinkles.
Fat: this is a “good fat” because it does a lot of for your skin!
Dermal-epidermal junction. It is very important in the aging process because over time its structure changes and leads to sagging and wrinkle formation.
Hypodermis: it is the innermost and thickest layer of skin.

Skin types

Most likely, your skin belongs to the 3 main categories (dry skin, normal skin, oily skin) and that throughout your life you go from one to another due to hormonal causes, climate changes, stress, …

What kind of skin do you have? Let's analyze each type to find out.

Dry Skin

Normal Skin

Oily Skin

Sensitive Skin

Combination Skin

Eczema, Psoriasis, and Rosacea

How to guess you have dry skin? Pay attention to tightness, flaking, roughness, itchiness, and an overall lack of pliability. Why is this the cause? Because there’s a lack of fluids in your skin.
Pros: less acne and blackheads.
Cons: Flakiness, uneven texture, fine lines, and wrinkles. And they can get worse cause of aging, if you usually travel by plane, the climate you live in, etc.
Maybe you belong to this group: people with normal and healthy skin, with an optimal water concentration. But that doesn’t mean that this will last forever: pay attention to possible skin changes!
This skin type is characterized by excess sebum, acne, blackhead congestion, large pores, shines at the end of the day, … And all this is generated by an enlargement of the sebaceous glands. But don't let this make you hate sebum because it has an important role in overall skin health and immunity.
Pros: it usually has less issues with fine lines and wrinkles.
Cons: shines all over your face as the hours go by, breakouts, trouble finding the right products,
It is not easy to define or categorize sensitive skin because it can be due to many causes: an allergic reaction, a reaction to a change in climate or lifestyle, ... Investigating the peculiarities and causes of your sensitive skin is key to build a right skincare routine.
Combination skin has dry patches and an oily T-zone (the area with more sebaceous glands). It usually needs different products for specific skin areas because it is not easy to manage its hydration.
Pros: you will learn a lot about cosmetics building the best routine for your combination skin.
Cons: it is very complicated to find all your skin needs in only one product.
These kinds of skins are characterized by compromised stratum corneum function and must be diagnosed and treated by dermatologists.


Many people underestimate this really important step in their skincare routine. Are you one of them? Let’s stop for a second and think about how many microbes and contaminants are in contact with your skin every day. You touch your face after touching the stair railings, your car’s steering wheel, your computer keys, the elevator buttons… Meanwhile, your skin is absorbing kitchen smoke, tobacco smoke, gas from cars in the street…

Do you need even more reasons?

Cleaning your face daily will help retard the aging process. A deficient cleansing or even worse, not cleansing at all, improves the creation of free radicals that attack the cells on your skin and accelerate wrinkling. 
Cleansing is an absolutely essential step in order for a skincare routine to work. Applying products over a dirty face is always a bad idea, the products won’t work as expected -in many cases they can even backfire. Plus, these products may spread dirt and microbes causing even more breakouts. 

Cleansers from a scientific perspective

Any cleanser is composed fundamentally of surfactants that have a hydrophilic head and a hydrophobic tail. These surfactants group in sphere-like micelles that work like this: micelles get in contact with dirt, adhere to it, and when you rinse out, both cleanser and dirt go away together.
How would a perfect cleanser be? The ideal cleanser should erase all kinds of dirt without altering the stratum corneum. Some surfactants may alter your skin, dry it out, irritate it due to a high pH… That’s why our cleansers are very carefully formulated, in order to get the perfect equilibrium between a deep cleanse and a gentle treatment. 

The Cleanser Landscape

What types of cleansers are there?

Micellar water


Gel Cleanser

Cream Cleanser

Powder cleanser

Cleansing balm

Bar Soap

Cleansing Oil

It is not only gentle but also highly effective at removing dirt, makeup and oil; it helps to clear out your pores. There are plenty of options depending on your skin type and needs: normal to dry skin, sensitive, acne-prone,...
The most handy option, quick and comfortable. But keep in mind that you should rinse your face after using them, to make sure no particles remain.
There are loads of options according to your skin type and necessities. Always read carefully the instructions to confirm that you are using it correctly (for example, some of them require hot water rinsing, others don’t, etc).
This kind of cleansers are deeply clarifying, but they also can be too stripping. It is highly recommended to read carefully the ingredients, specially if you have dry or sensitive skin.
Very effective, usually features a light exfoliation to the skin. If you have dry or sensitive skin beware of using it too often.
Probably the best alternative to oil cleansers if you like this kind of texture. They offer deep cleansing and are comfortable to use.
Mostly used in oily skin formulas, these are the most classic cleansers. Check the ingredients specially if you have sensitive or very dry skin, since some of them have a high pH that could be potentially irritating.
A great option to get rid of all kind of dirt in a gentle way. Choose the one that doesn’t leave a residue on your skin.
How to choose between so many options? You must search for a cleanser that effectively does its work, but gently, always keeping in mind what is your skin type and what are your favorite ingredients. Check out the surfactants, the pH, and if necessary, use more than one type of cleanser. 

Let’s take a look at each and every one of these aspects.

Know Your Surfactants

Here you have a detailed list of the main surfactants you may find in a cleanser, so you are prepared to choose the one that best suits your skin: 
On detailRecommended forNot recommended forHow to recognize it
CLASSIC SOAPVery effective regarding cleansing, but pay attention to their pH since some of them have a high pH that can irritate your skinNormal skin, oily skinDry skin, sensitive skin; problematic skin with issues such as eczema or rednessSodium hydroxide or potassium hydroxide appear in the ingredients list
SULFATESLow pH with a nice cleansing powerAlmost every skin typeSkin sensitive to sulfates surfactantsSLS (sodium lauryl sulfate) and SLES (sodium laureth sulfate) are the two main surfactants in this category. If you can choose, SLES is more skin-friendly
COCO BETAINEThe most usual type of cleanser. It’s gentle to the skin, purifies correctly, and usually makes bubblesPeople searching for a mild cleanserVery sensitive skin, or allergic to its surfactant (see below)Make sure you’re not allergic to “cocoamidopropyl betaine” or “coco betaine”, since this is the main surfactant and can be slightly allergic for some people. If you’re not sure, try it on your hand first
OTHER GENTLE SURFACTANSIf you have tried several cleansers but none of them seems the perfect one for you, check these out: sodium laureth sulfate (SLES), sodium cocoyl isethionate, alkyl sulfosuccinates,...Sensitive skin, skin suffering chronic drynessPeople who like bubbly cleansersCheck for ingredients like SCI (sodium cocoyl isethionate), glucosides (coco glucoside, lauryl glucosides), cocoamphoacetates or amino acids

Consider the pH

Skin’s natural acidity is something very important for its microbiome and general health. Normally, your skin’s pH is 5.5. If your skin is healthy, it will auto regulate the acidity even if you use a cleanser with a pH higher than that. But if your skin is dry, sensitive or if you suffer from eczema or psoriasis, you should pay special attention to your cleanser’s pH -it should be no higher than 5.5. Always keep in mind this advice: don’t listen to the miraculous promises of some cleanser brands. Even if this is an essential step, the cleanser’s goal is just to clean as gently as possible, and that’s it. 

Boost Your Cleansing Power

So, you already have your perfect cleanser, the one that does not irritate or dehydrate your skin, but you feel it’s not enough? You may complete your cleansing routine with these options:

Double cleansing

Cleansing device

You sure heard about this, since it’s pretty common in Asia. The first step is using an oil based cleanser, for example a cleansing oil or balm. This gets rid of all makeup and dirt. Then you apply a gentle cream or gel cleanser to make sure nothing remains over the skin, nor dirt nor oil.
These are gadgets that will help your cleanser penetrate the skin and develop their full power.

Cleanser Summarized

Still not sure about which cleanser to choose? We’ll give you some advice about which one to choose according to your skin type and lifestyle:

Makeup lovers

Too little time for your skincare routine?

Sensitive, itchy skin

Dry skin

Oily skin

If you use makeup on a daily basis, and specially if you like long lasting makeup, double cleansing is your perfect match! Use an oil, balm, or biphase cleanser as a first step, and finish with a mild gel or cream cleanser. 
Choose wet wipes and micellar water. Don’t forget to rinse for a flawless skin. 
You definitely want to choose a pH 5.5 cleanser, and check its surfactants to avoid any irritating ingredients.
Oil and balm cleansers are your perfect choice. Start with a fragrance-free, non foaming cream cleanser.
this may sound counterintuitive, but it’s absolutely true: don’t over clean your skin! It will backfire with grease production and unwanted shine. Choose a specific gel cleanser, or a soap formulated for oily skin.
And remember…
  • Don’t overdo it! There’s no need to cleanse more than twice a day (morning and night). If you overdo it you’ll end up dehydrating your skin. 
  • The ideal scenario is cleansing morning and night, right before bed. If you can’t do this, do it al least at nights.  
  • Don’t get carried away by frivolous fashions and flashy packagings. Check for the most effective cleanser according to your skin type. That will not always be the most expensive or the one on every ad.  
  • There’s no just one ideal cleanser for each type of skin. It depends on your skin’s current needs and preferences.  
  • If your skin feels dry or tight, either you’re cleaning too much or you need milder products. Pay attention to what your skin is telling you. 
  • Using SPF on a daily basis does not mean you need extra cleansing. Your usual routine will do.


A good skin hydration is key for a good skin barrier that keeps the good things in and keeps away the negative agents. Without this balance, all subsequent treatments will be useless. 
Let's take a quick look at the structure of our skin to understand the importance of moisturizers for your skin health. Do you remember that the outermost layer is called stratum corneum? Well, most cosmetics are developed to act at this level of the skin.

Skin Barrier Function 2: keep the good things in and the bad ones out

Moisturizers help your stratum corneum to properly develop its skin protection function: first line of defense to retain water and stop external damaging agents.

The Water-Based Stuff

Another key component of your skin's health is natural moisturizing factors (NMFs). These are water-based molecules that maintain skin elasticity and participate in the enzyme activity necessary for healthy cell turnover. PCA, lactic acid, free amino acids or urea are some of the most common NMFs.

All the bads of dry skin

Your stratum corneum may find that defending your skin from pollutants, UV rays, aging, etc. prevents it from performing its skin barrier function properly. When this happens, it especially affects dry and irritated skin and a vicious circle ensues: the stratum corneum fails to retain enough water, external agents enter, and inflammation, dehydration and less moisturizer absorption take place. If you don't do something about it, itchiness and skin flaking will appear, as well as wrinkles and fine lines in the long run.

Moisturizer Science

There are three main categories of moisturizer ingredients based on their function: humectants, emollients, and occlusives. Understanding how these ingredients work and finding the balance between them will help you unlock the key to moisturizing your skin. Keep in mind that your skin is constantly changing and there will be times when you may need to modify the moisturizing code that worked so well for you and adjust the categories.




What are humectants? They are ingredients that help your skin maintain the perfect level of hydration. This job is already done naturally by the NMFs in your skin, and humectants help them to do so.
What skin type needs products with humectants? All of them, from oily to dry. That’s why you will find them in many products such as moisturizing serums, ampoules, mists,.... 
Some of the best known humectants are: glycerin, hyaluronic acid, and glycols.
Emollients are moisturizers that soften your skin. They are usually made from substances such as jojoba oil, squalane, coconut alkanes and caprylic triglyceride. It won't come as a surprise then that the most common emollient products are face oils.  Emollients are perfect for both dry and oily skin. We recommend adding a few drops of them as a last step of your routine on those days when you feel your hydration is not enough.
Occlusives are substances that help our skin to protect itself from external agents such as UV light or pollution. How do they do it? Thanks to being heavy, fatty, waxy, they form an hydrophobic barrier and keep your skin moist.. Some of the most common occlusives: petrolatum, butters, waxes, and heavier silicones. Any skin type can benefit from the advantages of occlusives, especially dry skin.

Moisturizing Ingredients

Now that we know the categories, let's talk about the most effective ingredients within each category.


What is the best humectant? The answer is: none, the success lies in combining them. Each one of them has different additional benefits and combining them will help you give your skin the perfect hydration. What are the Representatives Moisturizing Forward Products? Cosmetic waters,essences, gels, moisturizing serums and most gel creams. Let's talk about each humectant in detail.


Lactid Acid




Hyaluronic Acid


Urea is an NMF that, unlike other moisturizers, not only hydrates your skin but also reinforces the skin protective barrier. 
Molecular weight: 60

Lactic acid is an NMF that in addition to moisturizing can be used in skin chemical exfoliation. 

Molecular weight: 90
Why is glycerin one of the most common humectants? Because it is one of the most effective at keeping your skin hydrated, soft, and supple. 

Molecular weight: 92
Panthenol is both a moisturizing and emollient ingredient. It stands out for its soothing properties. 

Molecular weight: 205
Perhaps when you hear collagen you think of anti-aging treatments, but the reality is that topical collagen cannot replace your natural collagen. However, it is a very effective ingredient to hydrate your skin. 

Molecular weight: 300,000
Perhaps when you hear collagen you think of anti-aging treatments, but the reality is that topical collagen cannot replace your natural collagen. However, it is a very effective ingredient to hydrate your skin. 

Molecular weight: 300,000
Most of the Hyaluronic Acids found in cosmetic products are high-molecular-weight polymers that are very effective in keeping the skin hydrated all day long. It is also present in smaller amounts in products that promise to plump, hydrate, and delay skin aging. 

Molecular weight: anywhere from 20,000 to 2 million+

Emollients and Face Oils 

Which is the Representative Emollient-Forward Product? Face oils! Facial oils go a long way in improving your skin's nourishment, softness, suppleness, and glow. On their own, they are not enough, but it can be very beneficial to add them to other moisturizers in your routine. In what cases?
  • When your moisturizer works well but you feel like you still need a little more hydration. A couple of drops of facial oil will complete the job of your favorite moisturizer. 
  • When your skin is dry but you don't want to use petrolatum/balm. Facial oils are lighter, but also less efficient. 
  • Lack of glowing skin? Facial oils will bring light back to your skin. 
  • Skin following an anti-acne treatment that is drying out the skin. A lightweight emollient can be very helpful to restore skin hydration. 
Remember: Face oils should be stored in cool places and avoid direct light or they may oxidize, go rancid, change color and have a bad odor. 
  • Face oils recommended for dry skin: Argan, Avocado, Jojoba, Marula, Olive, Macadamia Nut,... 
  • Face oils recommended for oily skin: Squalane, Hemp Seed, Rose Hip Seed, Evening Primrose, Chia,..


When the skin barrier is compromised, occlusives come into action to protect your skin from external elements and retain moisture.  Since occlusives can be heavier and greasier than other moisturizing ingredients, we recommend that oily skin use light creams with little or no occlusives, and dry skin use heavier creams with more occlusives. Let’s get closer to common occlusives...


Mineral Oil

Shea Butter




The occlusive par excellence. Petrolatum used in cosmetic products is highly refined so it does not irritate the skin or leave residues. 
A widespread belief regarding the use of petrolatum on the skin is that it is comedogenic, or that it clogs pores. But that is not true for high-purity petrolatum (the one used in cosmetics).

A lighter version of occlusives than petrolatum which makes the texture of the products more pleasant. 
This is a natural and versatile occlusive that’s produced from the nuts of the shea tree. Raw shea can be irritating so we recommend using it refined.
This occlusive is derived from wool. Many people show some kind of allergy to Lanolin, so we recommend you do a patch test before using it.
These occlusives are found naturally in beeswax, candelilla, carnauba,... Their main drawback is that their texture is not always the best, since their high melting point makes them unsuitable for high-level use. In order to apply and spread them correctly, they must be at a certain temperature, not always comfortable for your skin. 
One of the most effective and lightest occlusives. Silicone gel creams are a perfect choice for oily skin that needs extra hydration. How to find them? Look for dimethicone or "dimethicone crosspolymer" among the first ingredients.  Although you may have heard negative things about silicones, we recommend you try them on your skin. They are a very broad category and can bring you great benefits like mattifying your skin or even skin tone -in addition to providing beautiful textures and optically erasing wrinkles.

Moisturizing Products

Moisturizing products can be divided into: 
  • Basic moisturizers 
  • Enhancers
Enhancers Basic moisturizers are made of a mix of all the ingredients we have seen (humectants, emollients,...). Enhancers usually contain only one of these ingredients and serve to treat changes in our skin's hydration needs. Let's see what products we find in each category:

Basic Moisturizers


Gel Creams







Butters or salvers. They would be the last step in your moisturizing routine. Highly recommended for dry skin or to treat specific dehydrated areas.

This moisturizer has a high presence of humectants and usually contains silicon. Many of the moisturizers that claim "oil-free" are gel creams.
Heavier than moisturizing lotions. They are ideal for dry skin because they have more occlusives than other moisturizers. Most traditional moisturizers and night moisturizing masks belong to this type of moisturizer.
Toners, micellar waters, mists,... More than moisturizers, they would be a step after cleansing that gives a nice feeling.
Hydrating gels, serum or ampoules. The perfect booster for dry skin or the best moisturizer for oily skin.
Nowadays most of them are sheet masks. Recommended for all skin types who want to enjoy a “hydrating time”.
Nowadays most of them are sheet masks. Recommended for all skin types who want to enjoy a “hydrating time”.
Nowadays most of them are sheet masks. Recommended for all skin types who want to enjoy a “hydrating time”.

Your moisturizing routine

Well, at this point you are ready to build the best moisturizing routine for your skin. But, if you feel you still need some help, we are going to give you some keys depending on your skin type.

Normal Skin

Oily Skin

Sensitive Skin

Your ideal will be a mix of humectants, moisturizers, and balm or petrolatum. You need to combine them according to your skin needs.  
  • Humectants: an hydrating serum blend of humectants. 
  • Moisturizer: look for a cream or lotion with an occlusive such as mineral oil, petrolatum, or shea butter on the third or fifth position on the ingredients list. 
  • Balm or petrolatum: for dehydrated areas.

Oily skins have easier retaining moisture than dry skins, so their moisturizing routines are simpler. 
  • Build a routine centered around humectants and complement it with a few lightweight face oils. 
  • Another good option is to use silicone creams.
If you have sensitive skin always keep in mind: make it simple! More steps, more products, more chances of irritation. 
  • Look for ingredients and products that help you care for your skin barrier and retain moisture. 
  • For example, ceramides. We also recommend including softening ingredients.  

And remember: always follow your dermatologist's recommendations.

Seasonal Changes

Now you have everything under control… Seasonal changes appear! Skin is so dynamic and  sensitive to environmental changes: temperature, humidity,... 
For example, if you are moving to a colder place you should have a facial balm or oil at hand; however, if you are going to be in a warmer place we recommend using a gel or lighter moisturizer. 

Sun Protection

Sun protection is so important for your skin that it deserves an exclusive chapter. Imagine how important it is that if we could only stick to one step of the skincare routine, it would definitely be sunscreen. 
Let’s talk a little bit about sun rays to understand why they can be so harmful for our skin and health. 
The sun radiates its energy mainly as light, ultraviolet, and infrared radiation; and ultraviolet is the main responsible of skin damage and premature photoaging. 
There are three types of UV rays:




They are absorbed by the Earth’s atmosphere. The UV light you experience on Earth is either UVA or UVB, not UVC.

They can damage the outermost layers of your skin. They can cause sunspots, tanning, sunburns, and blistering, which can lead to skin cancer. 
They represent 95% of the UV rays that reach our skin. They go further than UVB and they reach out to our dermis. UVA rays are responsible for deep photoaging and enhanced skin cancer development. 

Spectrum of the Sun's Radiation

Too much sun exposure can damage the DNA in our skin cells. DNA tells our cells how to function. If enough DNA damage builds up over time, it can cause cells to start growing out of control, which can lead to skin cancer. Sun exposure can change depending on where you are. For example, in the mountains the atmosphere is thinner which also means more UV exposure; indoors the glasses protect you from UVB but not from UVA; on cloudy days there is less visible light but UV rays are still there touching your skin;...
Your skin tone also influences how your skin reacts to sun exposure. For that, dermatologists use the Fitzpatrick scale.
Here you can see how lighter skins burn more easily and have a higher risk of skin cancer. On the other extreme, darker skins are less likely to do both. But it does not mean darker skin should not use sunscreen: UV rays damage all skin types! 
In addition to skin cancer risks, too much sun exposure is the main cause of skin aging: spots, wrinkles, dullness,... 
How does it happen? As a defense mechanism to that exposure, your fibroblasts start to break down your collagen, you experience an overproduction of melanin that produces hyperpigmentation, the skin thickens, and in the long term wrinkles appear, dry, dull skin,... 
As you can see, the sun is one of the main external agents that cause premature aging. So much so that it has its own term: photoaging. Remember: using sun protection every day would be the best anti-aging product in your skincare routine!

The Science of Sunscreen 

How do sunscreens help you protect yourself from the sun? By absorbing harmful UVA and UVB rays. At this point we have to differentiate between:

Inorganic (mineral)

Organic (chemical)

They are minerals that are ground into fine particles. They sit on the surface of the skin and reflect UV rays away from your skin.

Chemical sunscreen ingredients form a thin protective film that absorbs UV radiation before it penetrates the skin. They usually have a nicer texture and less risk of leaving your face white.
What three things will be key to choosing your sunscreen? UVB protection (SPF), UVA protection, and texture. Let's look at each in detail.

UVB Protection (SPF)

There is a popular misconception that SPF relates to the time of solar exposure. This is not true because SPF is not directly related to the time of solar exposure but to the amount of solar exposure. Also, SPF is not on a linear scale. It means that for example, SPF30 doesn’t have twice the protection of SPF15. Actually, SPF15 means that it lets 1/15th, or about 7% of UVB through; and SPF 1/30th, about 3%.

UVA Protection

SPF protects your skin from UVB rays but you also need to protect it from UVB, the ones responsible for photoaging. Unfortunately, there is no universal label for UVB protection: in the US you will find a simple ”Broad spectrum”,  in the EU a ”UVA” label, and in Asia a ”PA+” label. We recommend you use sunscreen in the SPF 30-50 range. Maybe you have heard that you should protect your skin also from UVC rays, Blue Light or Infrared. You don’t have to worry too much about these rays because: as we saw before, UVC rays are absorbed by the Earth’s atmosphere; the amount of blue light you are exposed to from your mobile or computer is substantially less than from the sun, and antioxidants help you with that; Antioxidants help you too with Infrared Rays.

Sunscreen Texture

It is not easy to formulate a non-greasy sunscreen, with a light texture, which does not leave your skin white. So, although sunscreen is essential in your routine, we know that sometimes it takes work to incorporate it because it is difficult to find one with the perfect texture. Even if you want to use the highest SPF possible, we recommend finding sunscreens that you don’t mind applying daily and reapplying every two hours (40-80 min if you plan to spend time in the water).
The main sunscreen formats you will find are:

Lotions & fluids




Balms/ Sticks

Hybrid moisturizers

The basics. With many different textures, the ingredients list will help you to choose the right one.

Great format for beach days or when you are looking for glowy skin.
Easy to use and refreshing format. Just make sure you apply the necessary amount of sunscreen on all areas that should be protected.
The best format to apply over make-up. You only must pay attention to apply the right amount.
Very useful for travel or application in specific areas (under your eyes, your lips,...)
Best choice for the laziest ones. Moisturizing and protection in only one product. Just make sure you apply enough product and you reapply as sunscreen needs.

Beyond the Basics

What are we talking about when we say "treatments"? All those ingredients and products that we use on a daily basis to treat problems such as wrinkles, spots, flaccidity, etc. It is very important to know in detail these treatments in order to build an effective routine for our skin.  Behind each treatment, there is a series of active ingredients, some of them with multiple benefits and others that focus on a single skin problem.
As you can see, one active ingredient can target different skin issues at the same time, and various actives may target the same problem. Feeling overwhelmed? Don’t worry, we’ll guide you through each treatment so you can choose the best for your skin.  
There are a lot of active ingredients on the market: some of them very beneficial and others that are good for absolutely nothing. 
As you can see, it is not a simple task to choose the right active ingredient for each skin problem, even without considering your skin type.
To simplify this whole process, in the following pages, we are going to take a look at the truly worthy active ingredients, the ones with proven efficacy.

Real Efficacy of Active Ingredients

How do chemists test whether an active ingredient is effective or not? There are several methods:

In vitro

Ex vivo

In vivo animal

In vivo human

These tests are performed inside a tube. Cons: they cannot emulate how the skin absorbs the active ingredients to reach their target. They would serve as a first test for further testing.

These tests are made on a patch of removed skin (human or pig). Pros: you can see how the skin reacts to the active ingredients. Cons: the skin can only be used for a maximum of two weeks, which is not enough time to have data on the long-term behavior of the active ingredients.
Ingredients are tested on live animals in academic environments. This type of testing is becoming less and less common in the cosmetic world.
Most real scenario but… The most expensive one too! Therefore, very few actives are tested in humans.
Unfortunately, cosmetic tests are not as rigorous as drug tests.

Chemical Exfoliant types

We are going to introduce you to the skincare ABCs: four active ingredients that help us to treat a wide variety of skin concerns (wrinkles, texture, acne, tone,...). These are four active ingredients that have been tested and proven in many high quality clinical studies over the years.

  1. Chemical exfoliants. 
  2. Retinoids. 
  3. Vitamin C. 
  4. Niacinamide

Keep in mind when analyzing Active Ingredients

Concentration: In addition to choosing the right active ingredient, its dose is also very important. You should use the right one. 

Time: active ingredients need, at least, four weeks to start showing their benefits. Be patient! 

Mixing actives: you must be careful to use several active ingredients simultaneously to achieve the benefits of all of them. It is not always convenient to combine them all because your skin may become irritated, among other things. 

Derivatives: Within some active ingredients you will find that some derivatives are more efficient than others.

Chemical Exfoliants

Why exfoliate our skin? 

Our skin naturally undergoes a process whereby new cells appear and old ones disappear. It’s called the skin turnover rate. 

This cell renewal process is fundamental for healthy skin. Over time our skin begins to fail to perform this task properly due to factors such as aging, environmental stressors, and dehydration. And it becomes dull, rough, and without glow. 

How can we help our skin? Chemical exfoliants are the answer: these are acids that weaken the bonds between dead cells that have overstayed their welcome.

Best Active Ingredients

Chemical exfoliants will help your skin remove dead skin cells, and in the long run, can help with pigmentation, acne,... 
According to their function, they can be classified as follows:

Alpha Hydroxy Acids (AHAs)

Beta Hydroxy Acid (BHA)

Gentle Polyhydroxy Acid (PHA)

Water-soluble, weak acids. They are very effective in treating pigmentation, collagen production, fine lines, and wrinkles.
Glycolic, lactic, mandelic, malic, and tartaric acids, are AHAs.

Only one acid is found in this category: salicylic acid. Thanks to it being slightly soluble in oil, it can exfoliate down to the pore level. It's perfect for inflamed, acne-prone, and oily skin, due to its antimicrobial and anti-inflammatory properties.
These acids provide gentle exfoliation and keep moisture in the skin. They are therefore perfect for dry and sensitive skin, or skin that has not been helped by other acids. 

Which is the best way to add Chemical Exfoliants to my daily routine?

Chemical Exfoliants are beneficial for all skin types. You just have to find the right one for you. What things may you consider when choosing one?

Molecular size

Product type

The smaller the molecule, the more effective. But you cannot start using Chemical Exfoliants with the strongest ones. Later we will tell you how to do it little by little.

You can find Chemical Exfoliants in toners, serums, creams,... Which one to choose? You need to consider:

  • Concentration: you should look for products around these concentrations: 5–10% glycolic acid  > 8% lactic and mandelic acids 0.2–2% salicylic acid 10% gluconolactone 
  • pH: In general, around 3.5 there is little risk of irritation and you will still get the benefits of exfoliation.
  • Other ingredients: we recommend you look for Chemical Exfoliants with pH adjusters (to maintain and establish their pH)  and soothing ingredients such as Centella Asiatica or Calendula.

Which Chemical Exfoliants are right for your skin?

Here is some advice: 
  • Apply them in the evening after cleansing. 
  • Products with 10% concentration or less can be used daily. 
  • If your skin is sensitive, alternate nights. 
  • If you want to go a step further: try once a week with exfoliants with a higher concentration (more than 20%). These products are applied like a mask: they should be rinsed off after a few minutes. 
  • Sunscreen: you should always wear sunscreen (remember the previous chapter!). Even more, if you are using chemical exfoliants because your skin may be more sensitive to sun damage. 
  • Other products can help you: Clay masks and alcoholic toners will remove skin oil excess and make your chemical exfoliants more effective, with no need for higher concentration; petrolatum or balms will help you to protect small sensitive areas; …

Chemical Exfoliants Guide According to your skin type

Oily Skin

Normal Skin

Dry Skin

Sensitive Skin

The smaller the molecule, the more effective. But you cannot start using Chemical Exfoliants with the strongest ones. Later we will tell you how to do it little by little.

  • If your skin tolerates acids, start with 5-8% glycolic acid every other night. After two-three weeks if you have experienced some irritation, reduce concentration or use it less frequently. 
  • If not, increase concentration (no more than 12%) and/or use it nightly; add once a week 20-30% Glycolic Acid or Lactic Acid Mask. 
  • If you are not sure or your skin does not tolerate well acids: check out the dry skin guidelines.
Start with 5-10% lactic acid every night. After two or three weeks, if you have experienced some irritation, reduce concentration or use it less frequently. If not, swap lactic acid for glycolic acid nightly and add once a week 20-30% Glycolic Acid or Lactic Acid Mask.
  • If you have sensitive skin, you have been using acids for a few days and you have dryness, redness, irritation,... Stop using chemical exfoliants, and keep your healthy skincare routine: cleanser, moisturizer, and sunscreen. 
  • If it seems everything is ok, keep using them! 
  • If you do not see any differences in your skin (you have to wait at least four weeks), try going one step further. Start with 10-14% gluconolactone, and if you still do not see any improvements, keep trying in the following order: 10% mandelic acid, 5-10% lactic acid, and 5-10% glycolic acid.


Retinoid is a form of Vitamin A. It has gained popularity in the skincare market due to its anti-age power and its beneficial effects on acne and skin tone. 

We are sure retinoic acid, retinol, and retinyl palmitate sound somewhat familiar to you, right? They belong to the retinoids family, a big one! How can we classify its members?


Prescription Retinoids

Pharmacy Retinoids

Retinoids you can find at beauty stores

These retinoids are usually prescribed by dermatologists to combat moderate to severe acne. For example: Tazarotene, Tretinoin, or Isotretinoin.

Adapalene is a synthetic retinoid for mild to moderate acne and is available in pharmacies. We recommend combining it with a moisturizer to avoid dryness and irritation.
Retinol, Retinaldehyde, Retinyl Palmitate, Bakuchiol,... They are going to help you with wrinkles, pigmentation, and acne.
Retinol is not the most stable molecule. It is sensitive to light, air, and heat. With this in mind, you should:
  • Look for a container that protects the product from sun exposure and expose it to the air for as little time as possible.  
  • Store in a dark, cool place away from sun exposure.

Retinoids Benefits




Retinoids are considered one of the top ingredients against wrinkles because of their ability to promote collagen production, stimulate cell turnover, and prevent collagen degradation. Additionally, they can strengthen the epidermis and reduce the amount of water that passively evaporates from the skin.

Retinoids can improve the appearance of uneven skin tone, skin texture, and brighten the skin, due to their effect on cell turnover and collagen production. 
With acne, dead skin cells and gland oils block the hair follicles of the skin. Bacteria can also invade these blocked pores and cause pimples, blackheads,... Retinoids can reduce the abnormal skin peeling that blocks pores and unclog them, they balance sebum production and have soothing and antibiotic effects. 

But as you probably know, retinoids also have side effects like redness, flaking, or dryness. How to avoid them? You should add retinoids into your skincare routine quite slowly, starting with a low concentration.

Introducing Retinoids in your Skincare Routine

  • If you are a new to retinoids, we recommend you start in the 0.1–0.3% concentration range. Use 2–3 times a week until your skin gets used to this ingredient. 
  • If you are already using retinoids and been doing so for some time, you can go one step further with concentration 0.5–1.0%. Use it 2–3 times a week until skin has acclimated.  
  • It usually takes one to six months for the skin to adjust to retinoids.
Vitamin C is a highly effective antioxidant that reduces lines and wrinkles, helps even out skin tone, In addition to its antioxidant power, Vitamin C can be used to treat melasma and hyperpigmentation. 

It boosts collagen synthesis, so it helps with minimizing fine lines and wrinkles. In summary, the main benefits of Vitamin C are photoprotection, skin tone brightening, and collagen boosting. By incorporating Vitamin C correctly into our skincare routine we will see, in the short term, how our skin tone improves, and in the long term, we will reduce the signs of aging.

Vitamin C Family

Vitamin C is a large family of molecules. At the top is L-AA (pure vitamin C), which is the most beneficial. But it is not for all skin types because it sits at a lower pH. 

Then there are other derivatives of Vitamin C that also help our skin with photoprotection, brightening, and collagen boosting. Let's talk about the most common ones:

L-Ascorbic Acid

Magnesium Ascorbyl Phosphate

Sodium Ascorbyl Phosphate

Ascorbyl Glucoside

3-0 Ethyl Ascorbic Acid

The gold standard Vitamin C, why? Because it boosts collagen, photoprotects, and brightens your skin. But it may be quite irritating. If that’s the case for you, you should look for other options.

It helps to treat pigmentation.
It helps to fight acne.
It helps to combat acne and it has collagen-boosting benefits.
It helps to combat hyperpigmentation.

About L-Ascorbic Acid