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Skin science article

PCA Skin Collagen Hydrator Versus SkinMedica Ultra Sheer Moisturizer

PCA Skin Collagen Hydrator Versus SkinMedica Ultra Sheer Moisturizer This calming moisturizer is formulated around Butyrospermum Parkii Butter and Tetrahexyldecyl Ascorbate to calm redness and hydrate skin. This calming moisturizer is formulated around Tetrahe

PCA Skin Collagen Hydrator Versus SkinMedica Ultra Sheer Moisturizer

This calming moisturizer is formulated around Butyrospermum Parkii Butter and Tetrahexyldecyl Ascorbate to calm redness and hydrate skin.

This calming moisturizer is formulated around Tetrahexyldecyl Ascorbate and Panthenol to calm redness and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

C12-15 Alkyl Benzoate

Glycerin

Glyceryl Stearate

Cetearyl Alcohol

Isopropyl Palmitate

Butyrospermum Parkii Butter

Cyclopentasiloxane

Dimethicone

Cetyl Alcohol

Polysorbate 60

Tetrahexyldecyl Ascorbate

Allantoin

Aloe Barbadensis Leaf Extract

Chamomilla Recutita Flower Extract

Cucumis Sativus Fruit Extract

Ethylhexylglycerin

Glycol Distearate

Helianthus Annuus Seed Oil

Hydrolyzed Wheat Protein

Olea Europaea Fruit Oil

Phenoxyethanol

Potassium Cetyl Phosphate

Prunus Amygdalus Dulcis Oil

Sodium Hyaluronate

Sodium PCA

Tocopherol

Xanthan Gum

Carbomer

Sodium Hydroxide

Tetrasodium EDTA

Water, C12-15 Alkyl Benzoate, Glycerin, Glyceryl Stearate, Cetearyl Alcohol, Isopropyl Palmitate, Butyrospermum Parkii Butter, Cyclopentasiloxane, Dimethicone, Cetyl Alcohol, Polysorbate 60, Tetrahexyldecyl Ascorbate, Allantoin, Aloe Barbadensis Leaf Extract, Chamomilla Recutita Flower Extract, Cucumis Sativus Fruit Extract, Ethylhexylglycerin, Glycol Distearate, Helianthus Annuus Seed Oil, Hydrolyzed Wheat Protein, Olea Europaea Fruit Oil, Phenoxyethanol, Potassium Cetyl Phosphate, Prunus Amygdalus Dulcis Oil, Sodium Hyaluronate, Sodium PCA, Tocopherol, Xanthan Gum, Carbomer, Sodium Hydroxide, Tetrasodium EDTA

Cetyl Ethylhexanoate

Sorbitan Stearate

Methyl Gluceth-20

Tocopheryl Acetate

Panthenol

Ceteareth-20

Aminomethyl Propanol

Disodium EDTA

Potassium Sorbate

Water, Cetyl Ethylhexanoate, Sorbitan Stearate, Methyl Gluceth-20, Polysorbate 60, Dimethicone, Tocopherol, Tocopheryl Acetate, Tetrahexyldecyl Ascorbate, Panthenol, Sodium Hyaluronate, Cetearyl Alcohol, Ceteareth-20, Aminomethyl Propanol, Carbomer, Disodium EDTA, Phenoxyethanol, Ethylhexylglycerin, Potassium Sorbate

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Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite 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.

It plays several roles in a formula:

Typical 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.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl 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.

Here'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.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

Polysorbate 60 is used to help stabilize products. It is a surfactant and emulsifier. These properties help keep ingredients together in a product. Surfactants help reduce surface tension between ingredients with different states, such as liquids and solids. Emulsifiers help prevent oils and waters from separating.

Polysorbate 60 is sorbitol-based and created from the ethoxylation of sorbitan. Ethoxylation is a chemical reaction used to add ethylene oxide. Sorbitan is a the dehydrated version of sorbitol, a sugar found in fruits.

In this case, the 60 comes from reacting 60 units of ethylene oxide with sorbitan.

Polysorbates are commonly used in medicine and foods.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

Tetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.

THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).

Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) that mainly works on the surface.

Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.

Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on stubborn discoloration, even in melasma-prone skin.

A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).

While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.

THD is pretty stable, but it’s still vulnerable to degradation like ascorbic acid. Too much light or heat (above 113°F / 45°C) can break it down over time. Go for dark and opaque packaging that keeps it safe and shady!

Read more about other types of Vitamin C:

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

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

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Kaolin
  3. 03Charcoal Powder
  4. 04Glycerin
  5. 05Magnesium Aluminum Silicate
  6. 06Phenoxyethanol
  7. 07Caprylyl Glycol
  8. 08Xanthan Gum
  9. 09Citric Acid
  10. 10Ethylhexylglycerin
  11. 11Hexylene Glycol
  12. 12Disodium EDTA
  13. 13Water, Kaolin, Charcoal Powder, Glycerin, Magnesium Aluminum Silicate, Phenoxyethanol, Caprylyl Glycol, Xanthan Gum, Citric Acid, Ethylhexylglycerin, Hexylene Glycol, Disodium EDTA
  14. 14Alcohol Denat.
  15. 15Mel
  16. 16Prunus Amygdalus Dulcis Seed Meal
  17. 17Camphor
  18. 18Calcium Chloride
  19. 19Magnesium Chloride
  20. 20Sodium Chloride
Source · skinsort.com
02

Product index

Related product references

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PCA Skin Pro-max Age Renewal PCA Skin Pro-max Age Renewal ingredients explained: Water, Polysilicone-11, Propanediol, Glycerin, Butylene Glycol, PPG-3 Benzyl Ether Myristate, Polysorbate 20…

Source: incidecoder.comView reference →

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PCA Skin Pigment Gel Pro

PCA Skin Pigment Gel Pro PCA Skin Pigment Gel Pro ingredients explained: Water, Alcohol, Hamamelis Virginiana (Witch Hazel) Water, Butylene Glycol, Niacinamide, Lactic Acid, Gluconolactone,…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side