Follow us on our new Insta page »
Kiehl’s Ferulic Brew Antioxidant Facial Treatment With Lactic Acid

Ferulic Brew Antioxidant Facial Treatment With Lactic Acid

An antioxidant facial treatment fortified with ferulic & lactic acids (aha) to visibly boost glow, smooth skin's texture, & reduce fine lines in just seven days.
Uploaded by: abrooksmoyer on

Skim through

Ingredient name what-it-does irr., com. ID-Rating
Aqua/Water solvent
Arginine skin-identical ingredient goodie
Saccharomyces/Rice Ferment Filtrate (4.7%)
Dicaprylyl Ether emollient, solvent
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Pentylene Glycol solvent, moisturizer/​humectant
Lactic Acid (3.7%) exfoliant, moisturizer/​humectant, buffering superstar
Propanediol solvent, moisturizer/​humectant
Squalane skin-identical ingredient, emollient 0, 1 goodie
Butylene Glycol moisturizer/​humectant, solvent 0, 1
Sodium Chloride viscosity controlling
Tocopherol antioxidant 0-3, 0-3 goodie
Ascorbyl Glucoside antioxidant, skin brightening goodie
Salicylic Acid exfoliant, anti-acne, soothing, preservative superstar
Ferulic Acid (0.1%) antioxidant, antimicrobial/​antibacterial goodie
Caramel colorant
Adenosine cell-communicating ingredient goodie
Lavandula Hybrida Oil emollient
Helianthus Annuus Seed Oil/Sunflower Seed Oil emollient 0, 0 goodie
Cupressus Sempervirens Leaf/Nut/Stem Oil emollient
Anthemis Nobilis Flower Oil soothing, perfuming goodie
Linalool perfuming icky
Pelargonium Graveolens Flower Oil perfuming icky
Brassica Campestris Extract/Rapeseed Extract
Brassica Campestris Sprout Extract moisturizer/​humectant
Grape Seed antioxidant, emollient goodie
Sprout Extract antioxidant
Mentha Piperita Oil/Peppermint Oil perfuming icky
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Citronellol perfuming icky
Geraniol perfuming icky
Limonene perfuming, solvent icky
Origanum Majorana Leaf Oil

Kiehl’s Ferulic Brew Antioxidant Facial Treatment With Lactic Acid
Ingredients explained

Also-called: Aqua;Water | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

Arginine - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

We don't have description for this ingredient yet.

What-it-does: emollient, solvent

A clear, colorless and odorless oily liquid that works as a fast-spreading emollient with a dry skin feel

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent and a broad spectrum antimicrobial. According to manufacturer info, it's also a moisturizer and helps to make the product feel great on the skin. It works synergistically with preservatives and helps to improve water-resistance of sunscreens. 

Lactic Acid (3.7%) - superstar
  • It’s the second most researched AHA after glycolic acid
  • It gently lifts off dead skin cells to reveal newer, fresher, smoother skin
  • It also has amazing skin hydrating properties
  • In higher concentration (10% and up) it improves skin firmness, thickness and wrinkles
  • Choose a product where you know the concentration and pH value because these two greatly influence effectiveness
  • Don’t forget to use your sunscreen (in any case but especially so next to an AHA product)
Read all the geeky details about Lactic Acid here >>

Also-called: Zemea | What-it-does: solvent, moisturizer/humectant

Propanediol is a natural alternative for the often used and often bad-mouthed propylene glycol. It's produced sustainably from corn sugar and it's Ecocert approved. 

It's quite a multi-tasker: can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. 

Squalane - goodie
What-it-does: skin-identical ingredient, emollient | Irritancy: 0 | Comedogenicity: 1

It seems to us that squalane is in fashion and there is a reason for it. Chemically speaking, it is a saturated  (no double bonds) hydrocarbon (a molecule consisting only of carbon and hydrogen), meaning that it's a nice and stable oily liquid with a long shelf life. 

It occurs naturally in certain fish and plant oils (e.g. olive), and in the sebum (the oily stuff our skin produces) of the human skin. As f.c. puts it in his awesome blog post, squalane's main things are "emolliency, surface occlusion, and TEWL prevention all with extreme cosmetic elegance". In other words, it's a superb moisturizer that makes your skin nice and smooth, without being heavy or greasy.

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

Also-called: Salt | What-it-does: viscosity controlling

Sodium chloride is the fancy name of salt. Normal, everyday table salt

If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. The reason for this is that salt acts as a fantastic thickener in cleansing formulas created with ionic cleansing agents (aka surfactants) such as Sodium Laureth Sulfate. A couple of percents (typically 1-3%) turns a runny surfactant solution into a nice gel texture.

Tocopherol - goodie
Also-called: Vitamin E | What-it-does: antioxidant | Irritancy: 0-3 | Comedogenicity: 0-3
  • Primary fat-soluble antioxidant in our skin
  • Significant photoprotection against UVB rays
  • Vit C + Vit E work in synergy and provide great photoprotection
  • Has emollient properties
  • Easy to formulate, stable and relatively inexpensive
Read all the geeky details about Tocopherol here >>

Also-called: Form of Vitamin C | What-it-does: antioxidant, skin brightening

A form of skincare superstar, vitamin C. If you do not know why vitamin C is such a big deal in skincare, we have a really detailed, geeky description that's good to read. :) 

So now you know that because pure vitamin C is such a diva (very unstable and hard to formulate) the cosmetic industry is trying to come up with some derivatives that have the badass anti-aging properties of vitamin C (antioxidant protection + collagen boosting + fading hyperpigmentation) but without the disadvantages. This is a hard task, and there is not yet a derivative that is really proven to be better in every aspect, but Ascorbyl Glucoside is one of the best options when it comes to vitamin C derivatives. Let's see why:

Salicylic Acid - superstar
Also-called: BHA | What-it-does: exfoliant, anti-acne, soothing, preservative
  • It's one of the gold standard ingredients for treating problem skin
  • It can exfoliate skin both on the surface and in the pores
  • It's a potent anti-inflammatory agent
  • It's more effective for treating blackheads than acne
  • For acne combine it with antibacterial agents like benzoyl peroxide or azelaic acid
Read all the geeky details about Salicylic Acid here >>

Ferulic Acid (FA) is a goodie that can be found naturally in plant cell walls. There is a lot of it especially in the bran of grasses such as rice, wheat and oats. 

FA - whose main job is to be an antioxidant - owes its fame to a 2005 research that discovered that adding in 0.5% FA to a 15% Vitamin C + 1% Vitamin E solution not only stabilizes the highly unstable, divaish Vit C, but it also doubles the photoprotection abilities of the formula. 

What-it-does: colorant

The caramel in cosmetics is pretty much the same one that you know from the kitchen. It is derived by controlled heat treatment of food-grade carbohydrates (sugars) and works as a brown colorant

Adenosine - goodie

Adenosine is an important little compound in our body that has a vital cell-signalling role. Research on smearing it on our face is also promising and shows so far a couple of things:

  • It can help with wound healing
  • It’s a good anti-inflammatory agent
  • It might even help with skin’s own collagen production and improve skin firmness and elasticity
  • It helps with barrier repair and protection
  • It might be even useful for the hair helping with hair thickness and hair growth
What-it-does: emollient

We don't have description for this ingredient yet.

Also-called: Sunflower Oil;Helianthus Annuus Seed Oil | What-it-does: emollient | Irritancy: 0 | Comedogenicity: 0

Sunflower does not need a big intro as you probably use it in the kitchen as cooking oil, or you munch on the seeds as a healthy snack or you adore its big, beautiful yellow flower during the summer - or you do all of these and probably even more. And by even more  we mean putting it all over your face as sunflower oil is one of the most commonly used plant oils in skincare.

It’s a real oldie: expressed directly from the seeds, the oil is used not for hundreds but thousands of years. According to The National Sunflower Association, there is evidence that both the plant and its oil were used by American Indians in the area of Arizona and New Mexico about 3000 BC. Do the math: it's more than 5000 years – definitely an oldie.

What-it-does: emollient

We don't have description for this ingredient yet.

Also-called: Roman Chamomile Flower Oil | What-it-does: soothing, perfuming

The essential oil coming from the second most common type of chamomile, the Roman Chamomile. It also contains the biologically active anti-inflammatory componentsbisabolol, and chamazulene, but less than the more commonly used German Chamomile.  It's not clear what Roman Chamomile knows that the German one does not. 

Linalool - icky
What-it-does: perfuming, deodorant

Linalool is a super common fragrance ingredient. It’s kind of everywhere - both in plants and in cosmetic products. It’s part of 200 natural oils including lavender, ylang-ylang, bergamot, jasmine, geranium and it can be found in 90-95% of prestige perfumes on the market. 

The problem with linalool is, that just like limonene it oxidises on air exposure and becomes allergenic. That’s why a product containing linalool that has been opened for several months is more likely to be allergenic than a fresh one.

Also-called: Rose Geranium Flower Essential Oil | What-it-does: perfuming

The fragrant essential oil coming from the flowers of Rose Geranium. Like most essential oils, it contains antioxidant and antimicrobial components, but the main ones are fragrant constituents (like citronellol and geraniol). Be careful with it, if your skin is sensitive. 

Also-called: Rapeseed Extract;Brassica Campestris Extract

We don't have description for this ingredient yet.

What-it-does: moisturizer/humectant

We don't have description for this ingredient yet.

Grape Seed - goodie
Also-called: Grape Seed Oil;Vitis Vinifera Seed Oil | What-it-does: antioxidant, emollient

A goodie plant oil coming from the polyphenol-rich seeds of the grape. It's a light emollient oil that makes your skin feel smooth and nice and also contains a bunch of good-for-the-skin stuff. It's a great source of antioxidant polyphenols, barrier repair fatty acid linoleic acid (about 55-77%, while oleic acid is about 12-27%) and antioxidant, skin-protectant vitamin E

What-it-does: antioxidant

We don't have description for this ingredient yet.

Also-called: Peppermint Oil;Mentha Piperita Oil | What-it-does: perfuming

The essential oil coming from steam distillation of freshly harvested, flowering peppermint sprigs. Its major component is menthol that gives the oil its well-known refreshing and cooling properties. Peppermint oil is traditionally used as an inhalant for cold and coughs and there is also some clinical data validating its use against headaches by rubbing a peppermint oil cream on the forehead. 

As for skincare, other than the nice grassy-minty smell and the refreshing sensations, we cannot write good things. It can be a skin irritant, so much so that it is a well-known counterirritant for muscle pains creating mild surface irritation to make things better in the deeper layers. But for everyday skincare, counterirritation is not something you wanna do, so we think that peppermint oil is better to avoid, especially if your skin is sensitive. 

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

What-it-does: perfuming

Citronellol is a very common fragrance ingredient with a nice rose-like odor. In the UK, it’s actually the third most often listed perfume on the ingredient lists. 

It can be naturally found in geranium oil (about 30%) or rose oil (about 25%). 

Geraniol - icky
What-it-does: perfuming

Geraniol is a common fragrance ingredient. It smells like rose and can be found in rose oil or in small quantities in geranium, lemon and many other essential oils. 

Just like other similar fragrance ingredients (like linalool and limonene) geraniol also oxidises on air exposure and becomes allergenic. Best to avoid if you have sensitive skin.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

We don't have description for this ingredient yet.

You may also want to take a look at...

what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does emollient | solvent
A clear, colorless and odorless oily liquid that works as a fast-spreading emollient with a dry skin feel. 
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does solvent | moisturizer/humectant
A multi-functional, silky feeling helper ingredient that can do quite many things. It's used as an emulsion stabilizer, solvent, and a broad spectrum antimicrobial. [more]
what‑it‑does exfoliant | moisturizer/humectant | buffering
A superstar AHA that not only exfoliates skin but is also a very good moisturizer. In higher concentration (10% and up) it can even improve skin firmness, thickness, and wrinkles. [more]
what‑it‑does solvent | moisturizer/humectant
A natural corn sugar derived glycol. It can be used to improve skin moisturization, as a solvent, to boost preservative efficacy or to influence the sensory properties of the end formula. [more]
what‑it‑does skin-identical ingredient | emollient
irritancy, com. 0, 1
An emollient and natural moisturizer that can be found also in the sebum (oily stuff our skin produces). It leaves a nice non-greasy, non-heavy feeling on the skin. [more]
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does viscosity controlling
Sodium chloride is the fancy name of salt. Normal, everyday table salt.  If (similar to us) you are in the weird habit of reading the label on your shower gel while taking a shower, you might have noticed that sodium chloride is almost always on the ingredient list. [more]
what‑it‑does antioxidant
irritancy, com. 0-3, 0-3
Pure Vitamin E. Great antioxidant that gives significant photoprotection against UVB rays. Works in synergy with Vitamin C. [more]
what‑it‑does antioxidant | skin brightening
A stable and easy to formulate form of skincare superstar, vitamin C. In-vitro studies show that it shows all the three anti-aging benefits (antioxidant protection + collagen boosting + fading hyperpigmentation) that pure vitamin C does. [more]
what‑it‑does exfoliant | anti-acne | soothing | preservative
One of the gold standard ingredients for treating problem skin. It can exfoliate skin both on the surface and in the pores and it's a potent anti-inflammatory agent. [more]
what‑it‑does antioxidant | antimicrobial/antibacterial
A great antioxidant that is most famous for stabilizing the highly unstable Vitamin C. It also doubles the photoprotection abilities of Vit C+E formulas. [more]
what‑it‑does colorant
The caramel in cosmetics is pretty much the same one that you know from the kitchen. It is derived by controlled heat treatment of food-grade carbohydrates (sugars) and works as a brown colorant.  [more]
what‑it‑does cell-communicating ingredient
An important compound in our body that has a vital cell-signalling role. It is wound healing, anti-inflammatory and can help with barrier repair. [more]
what‑it‑does emollient
what‑it‑does emollient
irritancy, com. 0, 0
Sunflower Oil - it's a great emollient that protects & enhances the skin barrier. [more]
what‑it‑does emollient
what‑it‑does soothing | perfuming
The essential oil coming from the second most common type of chamomile, the Roman Chamomile. It also contains the biologically active anti-inflammatory components, bisabolol, and chamazulene, but less than the more commonly used German Chamomile. [more]
what‑it‑does perfuming
A super common fragrance ingredient that can be found among others in lavender, ylang-ylang, bergamot or jasmine. The downside of it is that it oxidises on air exposure and might become allergenic. [more]
what‑it‑does perfuming
The essential oil coming from the flowers of Rose Geranium. Like most essential oils, it contains antioxidant and antimicrobial components, but the main ones are fragrant constituents. [more]
what‑it‑does moisturizer/humectant
what‑it‑does antioxidant | emollient
A goodie plant oil coming from the polyphenol-rich seeds of the grape. It's a light emollient oil that is a great source of antioxidant polyphenols, barrier repair fatty acid linoleic acid and antioxidant, skin-protectant vitamin E. 
what‑it‑does antioxidant
what‑it‑does perfuming
The essential oil coming from steam distillation of freshly harvested, flowering peppermint sprigs. Its major component is menthol that gives the oil its well-known refreshing and cooling properties. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does perfuming
A common fragrance ingredient with a nice rose-like smell. [more]
what‑it‑does perfuming
A common fragrance ingredient that smells like rose and can be found in rose oil. [more]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]