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Paula's Choice Discoloration Repair Serum Versus Eucerin Hyaluron-Filler + Elasticity Night

Paula's Choice Discoloration Repair Serum Versus Eucerin Hyaluron-Filler + Elasticity Night This brightening serum is formulated around Niacinamide and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin. This anti-aging night moistur

Paula's Choice Discoloration Repair Serum Versus Eucerin Hyaluron-Filler + Elasticity Night

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

This anti-aging night moisturizer is formulated around Sodium Hyaluronate and Isobutylamido Thiazolyl Resorcinol to soften the look of wrinkles and fade the look of dark spots.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Niacinamide

Glycerin

Tranexamic Acid

C13-15 Alkane

Caprylic/Capric Triglyceride

Dicaprylyl Carbonate

Ethyl Macadamiate

Behenyl Alcohol

Glyceryl Stearate

Butylene Glycol

Silybum Marianum Seed Oil

Tocopherol

Lactobacillus/Coconut Fruit Juice Ferment Filtrate

Lecithin

Bakuchiol

Xanthan Gum

Caprylyl Glycol

Hydrogenated Lecithin

Allantoin

Glycine Soja Oil

Hexylene Glycol

Boerhavia Diffusa Root Extract

Glycine Soja Sterols

Citric Acid

Sodium Phytate

Malic Acid

Phenoxyethanol

Ethylhexylglycerin

Water, Niacinamide, Glycerin, Tranexamic Acid, C13-15 Alkane, Caprylic/Capric Triglyceride, Dicaprylyl Carbonate, Ethyl Macadamiate, Behenyl Alcohol, Glyceryl Stearate, Butylene Glycol, Silybum Marianum Seed Oil, Tocopherol, Lactobacillus/Coconut Fruit Juice Ferment Filtrate, Lecithin, Bakuchiol, Xanthan Gum, Caprylyl Glycol, Hydrogenated Lecithin, Allantoin, Glycine Soja Oil, Hexylene Glycol, Boerhavia Diffusa Root Extract, Glycine Soja Sterols, Citric Acid, Sodium Phytate, Malic Acid, Phenoxyethanol, Ethylhexylglycerin

Cetearyl Alcohol

Panthenol

Glyceryl Stearate Citrate

Hydroxypropyl Starch Phosphate

Argania Spinosa Kernel Oil

Hydrogenated Coco-Glycerides

Butyrospermum Parkii Butter

Sodium Hyaluronate

Arctium Lappa Fruit Extract

Creatine

1-Methylhydantoin-2-Imide

Isobutylamido Thiazolyl Resorcinol

Pantolactone

Tapioca Starch

Sodium Hydroxide

Dimethicone

Trisodium EDTA

1,2-Hexanediol

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Parfum

Water, Glycerin, Cetearyl Alcohol, Butylene Glycol, Caprylic/Capric Triglyceride, Panthenol, Glyceryl Stearate Citrate, Hydroxypropyl Starch Phosphate, Argania Spinosa Kernel Oil, Hydrogenated Coco-Glycerides, Butyrospermum Parkii Butter, Sodium Hyaluronate, Arctium Lappa Fruit Extract, Creatine, 1-Methylhydantoin-2-Imide, Isobutylamido Thiazolyl Resorcinol, Pantolactone, Tocopherol, Tapioca Starch, Xanthan Gum, Sodium Hydroxide, Citric Acid, Dimethicone, Trisodium EDTA, Caprylyl Glycol, 1,2-Hexanediol, Phenoxyethanol, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Parfum

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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.

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.

Caprylic/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.

Though 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.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While 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.

Fractionated 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.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This 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 at concentrations as low as 0.2%.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

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.

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.

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. 03Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).
  4. 04It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.
  5. 05This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.
  6. 06Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.
  7. 07The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.
  8. 08It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.
  9. 09Overall, avobenzone is a safe and regulated ingredient used in sunscreen for over 40 years.
  10. 10Diethylhexyl Syringylidenemalonate (DESM) is a photostabilizer, antioxidant, and SPF booster.
  11. 11One of DESM's main roles is stabilizing UV filters, especially avobenzone. Avobenzone is notoriously unstable when exposed to sunlight. By enhancing the stability of these filters, DESM helps maintain the sunscreen's effectivess through wear. It als…
  12. 12Besides enhancing UVA protection, DESM can boost the SPF of high-SPF formulations by up to 5 units.
  13. 13DESM also preserves the color integrity of cosmetic products and helps reduce the chance of yellowing of fading due to light exposure.
  14. 14This ingredient is typically found in concentrations between 0.3% - 0.5%. There are currently no maximum usage limits by regulatory bodies.
  15. 15Though this ingredient is a chemical UV filter, it can often be found in "100% mineral" sunscreens. This is due to regulatory loopholes.
  16. 16Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
  17. 17What it does:
  18. 18Dimethicone comes in different viscosities:
  19. 19Depending on the viscosity, dimethicone has different properties.
  20. 20Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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