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Skin science article

Paula's Choice Resist Ultra-Light Super Antioxidant Concentrate Serum Versus Renee Rouleau Skin Care Vitamin C & E Treatment

Paula's Choice Resist Ultra-Light Super Antioxidant Concentrate Serum Versus Renee Rouleau Skin Care Vitamin C & E Treatment This anti-aging serum is formulated around Resveratrol and Niacinamide to soften the look of wrinkles and calm redness. This brightenin

Paula's Choice Resist Ultra-Light Super Antioxidant Concentrate Serum Versus Renee Rouleau Skin Care Vitamin C & E Treatment

This anti-aging serum is formulated around Resveratrol and Niacinamide to soften the look of wrinkles and calm redness.

This brightening serum is formulated around Tetrahexyldecyl Ascorbate and Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Cyclopentasiloxane

Butylene Glycol

Dimethicone

Glycerin

Polysorbate 20

Polysilicone-11

Lauryl PEG-9 Polydimethylsiloxyethyl Dimethicone

Hyaluronic Acid

Resveratrol

Niacinamide

Quercetin

Adenosine

Tetrahexyldecyl Ascorbate

Tocopherol

Phospholipids

Ubiquinone

Epigallocatechin Gallate

Sea Whip Extract

Bisabolol

Beta-Glucan

Phytic Acid

Xanthan Gum

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Hydroxide

Disodium EDTA

Ethylhexylglycerin

Phenoxyethanol

Water, Cyclopentasiloxane, Butylene Glycol, Dimethicone, Glycerin, Polysorbate 20, Polysilicone-11, Lauryl PEG-9 Polydimethylsiloxyethyl Dimethicone, Hyaluronic Acid, Resveratrol, Niacinamide, Quercetin, Adenosine, Tetrahexyldecyl Ascorbate, Tocopherol, Phospholipids, Ubiquinone, Epigallocatechin Gallate, Sea Whip Extract, Bisabolol, Beta-Glucan, Phytic Acid, Xanthan Gum, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Hydroxide, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol

Helianthus Annuus Seed Oil

Diethylhexyl Succinate

Tocopheryl Linoleate/Oleate

PPG-12/Smdi Copolymer

Cetyl Alcohol

Ascorbyl Methylsilanol Pectinate

Dipotassium Glycyrrhizate

Tocopheryl Acetate

Terminalia Ferdinandiana Fruit Extract

Ascorbic Acid

Citrus Aurantium Dulcis Peel Oil

Citrus Grandis Peel Oil

Citrus Limon Peel Oil

Ascorbyl Palmitate

Butyrospermum Parkii Butter

Glycine Soja Seed Extract

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Carbomer

Polysorbate 60

Potassium Hydroxide

PEG-8

Methylpropanediol

Citric Acid

Water, Helianthus Annuus Seed Oil, Glycerin, Diethylhexyl Succinate, Dimethicone, Tocopheryl Linoleate/Oleate, PPG-12/Smdi Copolymer, Tetrahexyldecyl Ascorbate, Cyclopentasiloxane, Cetyl Alcohol, Ascorbyl Methylsilanol Pectinate, Dipotassium Glycyrrhizate, Tocopheryl Acetate, Terminalia Ferdinandiana Fruit Extract, Ascorbic Acid, Citrus Aurantium Dulcis Peel Oil, Citrus Grandis Peel Oil, Citrus Limon Peel Oil, Ascorbyl Palmitate, Butyrospermum Parkii Butter, Glycine Soja Seed Extract, Phytic Acid, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Carbomer, Xanthan Gum, Phenoxyethanol, Butylene Glycol, Ethylhexylglycerin, Polysorbate 60, Potassium Hydroxide, PEG-8, Methylpropanediol, Citric Acid

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

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.

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.

Phytic Acid is a gentle AHA and antioxidant. AHAs are chemical exfoliants that help remove dead skin cells. Phytic Acid has a slight and mild exfoliating effect.

The chemical makeup makes it classified as an AHA, much like lactic acid.

In some cases, it is a chelating agent. Chelating agents help prevent metals from binding to water, helping to stabilize the ingredients in a product.

An interesting fact about phytic acid is that it is considered an antinutrient. People do not have the enzyme needed to properly breakdown and digest phytic acid. When ingested, phytic acid binds to minerals and prevents them from being absorbed.

Read more about some other popular AHA's here:

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:

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.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Paula's Choice Calm Rescue & Repair Weightless MoisturizerIngredients explained

  1. 01Good 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.
  2. 02It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  3. 03Expand to read more
  4. 04Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  5. 05One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
  6. 06A natural moisturizer that’s also in our skin
  7. 07A super common, safe, effective and cheap molecule used for more than 50 years
  8. 08Not 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
  9. 09Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  10. 10High-glycerin moisturizers are awesome for treating severely dry skin
  11. 11A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by ever…
  12. 12A common multi-tasker fatty acid. It makes your skin feel nice and smooth (emollient), gives body to cream type products and helps to stabilize water and oil mixes (aka emulsions).
  13. 13A light, oily liquid (triglyceride of seven carbon length fatty acid, heptanoic acid) that works as a very high spreadability and low viscosity emollient making the skin nice and smooth.
  14. 14We don't have description for this ingredient yet.
  15. 15Butylene 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.
  16. 16BG’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…
  17. 17It’s an ingredient whose safety hasn’t been questioned so far by anyone (at least not that we know about). BG is approved by Ecocert and is also used enthusiastically in natural products. BTW, it’s also a food additive.
  18. 18Propanediol 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.
  19. 19It'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.
  20. 20A naturally occurring fructose polysaccharide found in the roots and rhizomes of several plants, for example, chicory. It is used in skincare for its prebiotic activity, meaning that it reduces the growth of bad bacteria in favor of friendly microor…
Source · incidecoder.com
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Product index

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Comparison edit

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