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PCA Skin Collagen Hydrator Versus IMAGE skincare Vital C Hydrating Repair Cream

PCA Skin Collagen Hydrator Versus IMAGE skincare Vital C Hydrating Repair Cream This calming moisturizer is formulated around Butyrospermum Parkii Butter and Tetrahexyldecyl Ascorbate to calm redness and hydrate skin. This barrier-repair night moisturizer is f

PCA Skin Collagen Hydrator Versus IMAGE skincare Vital C Hydrating Repair Cream

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

This barrier-repair night moisturizer is formulated around Aloe Barbadensis Leaf Juice and Tetrahexyldecyl Ascorbate to strengthen the skin barrier 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

Aloe Barbadensis Leaf Juice

Isostearyl Neopentanoate

PEG-100 Stearate

Simmondsia Chinensis Seed Oil

Caprylic/Capric Triglyceride

Citrus Aurantium Dulcis Oil

Limonene

Brassica Campestris/Aleurites Fordi Oil Copolymer

Stearyl Alcohol

Ceteth-10 Phosphate

Dicetyl Phosphate

Magnesium Ascorbyl Phosphate

Panthenol

Squalane

Caprylyl Glycol

Glycine Soja Sterols

Linoleic Acid

Phospholipids

Glucosamine Hcl

Hexylene Glycol

Magnesium Aluminum Silicate

PEG-8

Butylene Glycol

Phytic Acid

Pisum Sativum Extract

Retinyl Palmitate

Bambusa Vulgaris Leaf/Stem Extract

Citrus Nobilis Peel Oil

Yeast Polysaccharides

Dipotassium Glycyrrhizate

Disodium EDTA

Benzoic Acid

Ascorbyl Palmitate

Pyruvic Acid

Tremella Fuciformis Sporocarp Extract

Citric Acid

Ascorbic Acid

Vitis Vinifera Seed Extract

Aloe Barbadensis Leaf Juice, Water, Glycerin, Dimethicone, C12-15 Alkyl Benzoate, Glyceryl Stearate, Isostearyl Neopentanoate, PEG-100 Stearate, Simmondsia Chinensis Seed Oil, Caprylic/Capric Triglyceride, Cetearyl Alcohol, Citrus Aurantium Dulcis Oil, Limonene, Brassica Campestris/Aleurites Fordi Oil Copolymer, Cetyl Alcohol, Tetrahexyldecyl Ascorbate, Stearyl Alcohol, Phenoxyethanol, Cyclopentasiloxane, Tocopherol, Ceteth-10 Phosphate, Dicetyl Phosphate, Magnesium Ascorbyl Phosphate, Panthenol, Squalane, Caprylyl Glycol, Glycine Soja Sterols, Linoleic Acid, Phospholipids, Ethylhexylglycerin, Glucosamine Hcl, Hexylene Glycol, Xanthan Gum, Magnesium Aluminum Silicate, PEG-8, Butylene Glycol, Phytic Acid, Sodium Hydroxide, Pisum Sativum Extract, Allantoin, Retinyl Palmitate, Bambusa Vulgaris Leaf/Stem Extract, Citrus Nobilis Peel Oil, Yeast Polysaccharides, Dipotassium Glycyrrhizate, Disodium EDTA, Sodium Hyaluronate, Benzoic Acid, Ascorbyl Palmitate, Pyruvic Acid, Tremella Fuciformis Sporocarp Extract, Citric Acid, Ascorbic Acid, Vitis Vinifera Seed Extract

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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.

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

C12-15 Alkyl Benzoate is a lightweight emollient made by combinig benzoic acid with fatty alcohols that are 12-15 carbons long.

In cosmetics, it plays several roles:

The Cosmetic Review Expert Panel has concluded the alkyl benzoate group to be safe as used in cosmetics; it wasn't found to be a skin irritant and unlikely to be absorbed due to its low water solubility.

This report recorded almost 1000 reported uses with concentrations up to 59% in leave-on products but your cosmetics will typically use 0.5-15% depending on the product.

It's often called a "SPF booster": this is because it keeps UV filters properly dissolved and evenly distributed to support a sunscreen's performance. It doesn't actually raise SPF on its own.

Overall, this ingredient is well tolerated.

This ingredient is fungal acne safe because it is an ester of benzoic acid.

Think of this ingredient as two parts stuck together: an oily part and an acid part. Malassezia only gets a meal when it can snip off a fatty acid to eat. With C12-15 Alkyl Benzoate, the acid part is benzoic acid, which isn't a fatty acid and which the yeast can't use as food.

Benzoic acid is actually used as a preservative to stop yeast from growing.

The oily part is a blend of C12-15 fatty alcohols but fatty alcohols in this size range can support only a little Malassezia growth (mostly for one species of Malassezia as well).

In the ingredient, those alcohols stay locked inside the molecule. The yeast can only reach them by snipping the benzoate bond, and that type of bond is harder for it to cut than a normal fatty bond.

So not much gets released. And whatever does get snipped comes packaged with benzoic acid, which discourages yeast growth.

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.

Cetyl Alcohol is a fatty alcohol. Fatty Alcohols are most often used as an emollient or to thicken a product.

Its main roles are:

Though it has "alcohol" in the name, it is not related to denatured alcohol or ethyl alcohol.

The FDA allows products labeled "alcohol-free" to have fatty alcohols.

This ingredient may not be fungal acne safe. It is a primary fatty alcohol with a chain length above 12 carbons. A study from 2019 show Malassezia can feed on fatty alcohols in this range, so it may trigger fungal acne in those prone to it.

Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.

Since D5 is volatile, it does its thing and then evaporates off the skin quickly.

The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics

There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.

Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.

The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.

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.

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.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

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.

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.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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 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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  7. 07The 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 …
  8. 08Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  9. 09Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  10. 10Topically, glycerin does several things at once:
  11. 11Your 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.
  12. 12Aquaporin-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.
  13. 13This 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.
  14. 14Just know very high concentrations (>40%) can feel tacky in low humidity.
  15. 15Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  16. 16Hexylene Glycol is a multitasker ingredient that works as a solvent, humectant, emulsifier, viscosity reducer, and preservative booster.
  17. 17It is able to dissolve both water and oil-soluble ingredients to stabilize tricky actives and make products spread more easily.
  18. 18As a humectant, it pulls water into the skin. But it's a pretty minor moisturizing ingredient compared to other humectants, like glycerin.
  19. 19Interestingly, it can act as a mild penetration enhancer. One in vitro study on human skin found a 12% concentration upped the absorption of mometasone furoate (a medicinal ingredient used to treat inflammatory skin conditions) up to 7%.
  20. 20This ingredient is typically used at levels of 0.1-10% depending on the role it's playing.
Source · skinsort.com
02

Product index

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03

Comparison edit

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