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Skin science article

Makeup Artist's Choice Fade Serum Versus PCA Skin Hydrating Serum

Makeup Artist's Choice Fade Serum Versus PCA Skin Hydrating Serum This brightening serum is formulated around Alpha-Arbutin and Kojic Acid to fade the look of dark spots and brighten dull-looking skin. This hydrating serum is formulated around Sodium PCA and A

Makeup Artist's Choice Fade Serum Versus PCA Skin Hydrating Serum

This brightening serum is formulated around Alpha-Arbutin and Kojic Acid to fade the look of dark spots and brighten dull-looking skin.

This hydrating serum is formulated around Sodium PCA and Aloe Barbadensis Leaf Juice to hydrate skin and calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Sd Alcohol 40

Ethoxydiglycol

Propylene Glycol

Alpha-Arbutin

Kojic Acid

Glycerin

Glycyrrhiza Glabra Root Extract

Morus Alba Leaf Extract

Panax Ginseng Berry Extract

Resveratrol

Hydroxyethylcellulose

Butylene Glycol

Sodium Lactate

Sodium PCA

Glycine

Fructose

Urea

Niacinamide

Inositol

Sodium Benzoate

Lactic Acid

Sd Alcohol 40, Ethoxydiglycol, Propylene Glycol, Alpha-Arbutin, Kojic Acid, Glycerin, Glycyrrhiza Glabra Root Extract, Morus Alba Leaf Extract, Panax Ginseng Berry Extract, Resveratrol, Hydroxyethylcellulose, Butylene Glycol, Sodium Lactate, Sodium PCA, Glycine, Fructose, Urea, Niacinamide, Inositol, Sodium Benzoate, Lactic Acid

Water

Sodium Polyacrylate

Aloe Barbadensis Leaf Juice

Gluconolactone

Sodium Hyaluronate

Wheat Amino Acids

Triticum Vulgare Germ Extract

Panthenol

Symphytum Officinale Leaf Extract

Saccharomyces Lysate Extract

Hydroxyproline

Water, Glycerin, Sodium Polyacrylate, Sodium PCA, Aloe Barbadensis Leaf Juice, Sodium Lactate, Gluconolactone, Sodium Hyaluronate, Wheat Amino Acids, Triticum Vulgare Germ Extract, Sodium Benzoate, Panthenol, Symphytum Officinale Leaf Extract, Saccharomyces Lysate Extract, Hydroxyproline, Fructose, Glycine, Inositol, Niacinamide, Urea

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Fructose is fruit/plant sugar. It can be found in apples, figs, and honey.

This ingredient is a humectant. Humectants help draw moisture from the air to your skin, keeping your skin hydrated.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Glycine is the smallest amino acid and a key building block of collagen. It's part if your skin's Natural Moisturizing Factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

A study from 2022 found that an amino acid complex featuring taurine, arginine, and glycine significantly reduced skin irritation, improved redness, and accelerated the skin repair process.

Inositol is a sugar alcohol naturally found in the human body. Our bodies use this ingredient in the process of growing new cells.

Studies show inositol to be a key component for keratinocyte growth.

Keratinocytes make up the majority of the outermost layer of skin. These cells protect our skin from UV exposure, infection, and help keep skin hydrated.

This ingredient is also considered a humectant. Humectants help hydrate the skin by drawing moisture to it.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Sodium Lactate is the sodium salt of lactic acid, an AHA. It is a humectant and sometimes used to adjust the pH of a product.

This ingredient is part of our skin's NMF, or natural moisturizing factor. Our NMF is essential for the hydration of our top skin layers and plasticity of skin. NMF also influences our skin's natural acid mantle and pH, which protects our skin from harmful bacteria.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Sodium PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

Urea is also called carbamide and is the diamide of carbonic acid. In cosmetics, urea is used to hydrate the skin. It also provides exfoliation in higher concentrations.

As a humectant, urea helps draw moisture from the air and from deep within the skin. This helps hydrate your skin. Studies show urea is an effective moisturizer for dry skin conditions. 40% urea is typical in medications for treating eczema and other skin conditions.

Urea has the strongest exfoliation effect in concentrations higher than 10%. It is a keratolytic agent, meaning it breaks down the keratin protein in the top layer of skin. This helps remove dead skin cells and flaking skin.

In medicine, urea has been shown to help increase the potency of other ingredients, such as fungal treatments.

Humans and animals use urea to metabolize nitrogen-containing compounds. Urea is highly soluble in water. Once dissolved, it is neither acidic nor alkaline.

Urea is actually one of the more well-studied and well-supported ingredients out there if you have eczema.

Clinical trials have shown that urea creams in the 5 - 10% range can:

Higher concentrations (20 -30%) can also help with thickened, scaly patches but is also more likely to sting on active flares.

Skip urea if you have rosacea. The AAD (American Academy of Dermatology) lists it alongside alcohol, menthol, and fragrance as a potential irritant for rosacea-prone skin. Urea's keratolytic and penetration-enhancing properties can trigger stinging, burning, and redness.

As always, your skin is unique, so definitely check in with your dermatologist.

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.
  4. 04Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.
  5. 05In practice, that translates to a long shelf life and a consistently elegant skin feel.
  6. 06While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.
  7. 07Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
  8. 08This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  9. 09This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures…
  10. 10Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  11. 11Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  12. 12Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  13. 13Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  14. 14Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.
  15. 15It plays several roles in a formula:
  16. 16Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.
  17. 17Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  18. 18However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  19. 19Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.
  20. 20Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.
Source · skinsort.com
02

Product index

Related product references

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PCA Skin Nutrient Toner

PCA Skin Nutrient Toner PCA Skin Nutrient Toner ingredients explained: Water/Aqua/Eau, Lactobacillus/Pumpkin Ferment Extract, Sucrose, Lactic Acid, Propylene Glycol, Citric Acid, Glutathion…

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Comparison edit

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