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Skin science article

Paula's Choice Resist Anti-Aging Clear Skin Hydrator Versus La Roche-Posay Rosaliac UV Legere

Paula's Choice Resist Anti-Aging Clear Skin Hydrator Versus La Roche-Posay Rosaliac UV Legere This anti-aging moisturizer is formulated around Sodium Ascorbyl Phosphate and Niacinamide to soften the look of wrinkles and balance excess oil. This calming day moi

Paula's Choice Resist Anti-Aging Clear Skin Hydrator Versus La Roche-Posay Rosaliac UV Legere

This anti-aging moisturizer is formulated around Sodium Ascorbyl Phosphate and Niacinamide to soften the look of wrinkles and balance excess oil.

This calming day moisturizer is formulated around Niacinamide and Ascorbyl Glucoside to calm redness and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Cyclopentasiloxane

Octyldodecyl Neopentanoate

Vinyl Dimethicone/Methicone Silsesquioxane Crosspolymer

Glycerin

Sodium Ascorbyl Phosphate

Cetyl Alcohol

Niacinamide

Dimethicone

Cetearyl Alcohol

Butylene Glycol

Glyceryl Stearate

PEG-100 Stearate

Adenosine

Epigallocatechin Gallate

Glucose Oxidase

Lactoperoxidase

Boerhavia Diffusa Root Extract

Cocos Nucifera Fruit Extract

Lactobacillus

Polysilicone-11

Sodium Chloride

Potassium Thiocyanate

Glucose

Xanthan Gum

Ceteareth-20

Decyl Glucoside

Citric Acid

Phenoxyethanol

Water, Cyclopentasiloxane, Octyldodecyl Neopentanoate, Vinyl Dimethicone/Methicone Silsesquioxane Crosspolymer, Glycerin, Sodium Ascorbyl Phosphate, Cetyl Alcohol, Niacinamide, Dimethicone, Cetearyl Alcohol, Butylene Glycol, Glyceryl Stearate, PEG-100 Stearate, Adenosine, Epigallocatechin Gallate, Glucose Oxidase, Lactoperoxidase, Boerhavia Diffusa Root Extract, Cocos Nucifera Fruit Extract, Lactobacillus, Polysilicone-11, Sodium Chloride, Potassium Thiocyanate, Glucose, Xanthan Gum, Ceteareth-20, Decyl Glucoside, Citric Acid, Phenoxyethanol

Isononyl Isononanoate

Octocrylene

Ethylhexyl Salicylate

Diisopropyl Sebacate

Sucrose Tristearate

Butyl Methoxydibenzoylmethane

Cyclohexasiloxane

Ammonium Polyacryloyldimethyl Taurate

Methylsilanol/Silicate Crosspolymer

Drometrizole Trisiloxane

Ascorbyl Glucoside

Polysorbate 61

PEG-12 Dimethicone

Dimethiconol

Caffeine

Sodium Citrate

Sodium Hydroxide

Sodium Stearoyl Glutamate

Disodium EDTA

Sodium Benzoate

Caprylyl Glycol

CI 19140

CI 42090

Water, Isononyl Isononanoate, Glycerin, Octocrylene, Niacinamide, Ethylhexyl Salicylate, Diisopropyl Sebacate, Dimethicone, Sucrose Tristearate, Butyl Methoxydibenzoylmethane, Cyclohexasiloxane, Ammonium Polyacryloyldimethyl Taurate, Methylsilanol/Silicate Crosspolymer, Drometrizole Trisiloxane, Ascorbyl Glucoside, Polysorbate 61, PEG-12 Dimethicone, Dimethiconol, Caffeine, Sodium Citrate, Sodium Hydroxide, Sodium Stearoyl Glutamate, Disodium EDTA, Citric Acid, Xanthan Gum, Sodium Benzoate, Phenoxyethanol, Caprylyl Glycol, CI 19140, CI 42090

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

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.

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.

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.

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.

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. 03This ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.
  4. 04Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).
  5. 05In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).
  6. 06Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
  7. 07Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
  8. 08While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
  9. 09This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
  10. 10Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
  11. 11You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.
  12. 12The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.
  13. 13Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.
  14. 14Ceramide EOP is formally known as Ceramide 1.
  15. 15It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.
  16. 16EOP stands for a linked Ester fatty acid, a linked Omega hydroxy fatty acid, and the Phytosphingosine base.
  17. 17What makes Ceramide EOP special is its ultra-long fatty acid chain; this unique structure allows it to bridge the lipid layers in your skin barrier to prevent water loss (something no other ceramide can do).
  18. 18Low levels of Ceramide EOP have been found in people with eczema and psoriasis.
  19. 19Using it together with other ceramides, cholesterol, and linoleic acid have been shown to meaningfully improve hydration and reduce water loss.
  20. 20In one clinical study, a regimen using Ceramide EOP, NP, and AP led to significant symptom improvements in patients with eczema, psoriasis, and dry skin in just 4 weeks.
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

Read side by side