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Skin science article

ZO Skin Health Daily Power Defense Versus Paula's Choice Calm Repairing Serum

ZO Skin Health Daily Power Defense Versus Paula's Choice Calm Repairing Serum This barrier-repair moisturizer is formulated around Laminaria Digitata Extract and Beta-Glucan to strengthen the skin barrier and hydrate skin. This calming serum is formulated arou

ZO Skin Health Daily Power Defense Versus Paula's Choice Calm Repairing Serum

This barrier-repair moisturizer is formulated around Laminaria Digitata Extract and Beta-Glucan to strengthen the skin barrier and hydrate skin.

This calming serum is formulated around Sodium Hyaluronate and Ceramide NP to calm redness and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Dicaprylyl Carbonate

Cetearyl Isononanoate

Glycerin

Pentylene Glycol

Cetearyl Alcohol

Steareth-20

Safflower Oil/Palm Oil Aminopropanediol Esters

Laminaria Digitata Extract

Opuntia Ficus-Indica Stem Extract

Arabidopsis Thaliana Extract

Marrubium Vulgare Meristem Cell Culture

Leontopodium Alpinum Meristem Cell Culture

Retinyl Palmitate

Tocopheryl Acetate

Tocopherol

Micrococcus Lysate

Caprylyl Glycol

Hexylene Glycol

Lactose

Galactoarabinan

Lecithin

Schizophyllan

Beta-Glucan

1,2-Hexanediol

Carbomer

Cellulose

Maltodextrin

C14-22 Alcohols

Cetearyl Glucoside

C12-20 Alkyl Glucoside

Hydroxypropyl Methylcellulose

Disodium EDTA

Sodium Hydroxide

Phenoxyethanol

Ethylhexylglycerin

Sodium Benzoate

Parfum

CI 77007

Limonene

Water, Dicaprylyl Carbonate, Cetearyl Isononanoate, Glycerin, Pentylene Glycol, Cetearyl Alcohol, Steareth-20, Safflower Oil/Palm Oil Aminopropanediol Esters, Laminaria Digitata Extract, Opuntia Ficus-Indica Stem Extract, Arabidopsis Thaliana Extract, Marrubium Vulgare Meristem Cell Culture, Leontopodium Alpinum Meristem Cell Culture, Retinyl Palmitate, Tocopheryl Acetate, Tocopherol, Micrococcus Lysate, Caprylyl Glycol, Hexylene Glycol, Lactose, Galactoarabinan, Lecithin, Schizophyllan, Beta-Glucan, 1,2-Hexanediol, Carbomer, Cellulose, Maltodextrin, C14-22 Alcohols, Cetearyl Glucoside, C12-20 Alkyl Glucoside, Hydroxypropyl Methylcellulose, Disodium EDTA, Sodium Hydroxide, Phenoxyethanol, Ethylhexylglycerin, Sodium Benzoate, Parfum, CI 77007, Limonene

Sodium Lauroyl Lactylate

Sodium Hyaluronate

Polysorbate 20

Caprylic/Capric Triglyceride

PEG/PPG-14/4 Dimethicone

Xanthan Gum

Sodium Cocoyl Amino Acids

Ceramide NP

Epilobium Angustifolium Extract

Ceramide AP

Cholesterol

Phytosphingosine

Sarcosine

Chrysanthemum Parthenium Flower Extract

Sea Whip Extract

Glycine Soja Seed Extract

Hyaluronic Acid

Glycyrrhiza Glabra Root Extract

Ceramide EOP

Magnesium Aspartate

Potassium Aspartate

Ubiquinone

Leuconostoc/Radish Root Ferment Filtrate

Calcium Chloride

Propylene Glycol

Sodium Metabisulfite

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Potassium Sorbate

Water, Glycerin, Sodium Lauroyl Lactylate, Sodium Hyaluronate, Polysorbate 20, Caprylic/Capric Triglyceride, PEG/PPG-14/4 Dimethicone, Xanthan Gum, Disodium EDTA, Sodium Cocoyl Amino Acids, Ceramide NP, Ethylhexylglycerin, Epilobium Angustifolium Extract, Ceramide AP, Cholesterol, Phytosphingosine, Beta-Glucan, Sarcosine, Carbomer, Chrysanthemum Parthenium Flower Extract, Sea Whip Extract, Glycine Soja Seed Extract, Hyaluronic Acid, Glycyrrhiza Glabra Root Extract, Ceramide EOP, Magnesium Aspartate, Potassium Aspartate, Ubiquinone, Phenoxyethanol, 1,2-Hexanediol, Caprylyl Glycol, Leuconostoc/Radish Root Ferment Filtrate, Calcium Chloride, Propylene Glycol, Tocopherol, Sodium Metabisulfite, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Benzoate, Potassium Sorbate

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

Beta-Glucan is a soluble polysaccharide (a chain of glucose sugars) sourced from the cells walls of oats, baker's yeast, mushrooms, and seaweed.

It's a rare ingredient that pulls double-duty as a heavy-duty hydrator and skin-soothing repair agent.

On the surface, it acts as a humectant that holds water in place and reduces moisture loss for a plumper, smoother feel, while its anti-inflammatory and antioxidant properties make it a great pick for calming redness or sensitive skin

The more interesting story is underneath:

Despite its large molecular size, oat beta-glucan has been shown to penetrate the epidermis and reach the dermis by slipping between skin cells. Here, it interacts with fibroblasts and macrophages to nudge collagen synthesis and support wound repair.

A small 2005 split-face clinical study of 27 subjects found topical beta-glucan produced measurable reductions in wrinkle depth, height, and roughness after 8 weeks of use.

It is worth noting the trial was small and the penetration testing used frozen, irradiated skin so the anti-aging data is encouraging rather than definitive.

This ingredient gets along with pretty much everything and is typically used around 0.1-1%.

Fungal acne: This ingredient is not a food source for the Malassezia yeast because it is a glucose polysaccharide with no fatty acid or ester component.

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).

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.

Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.

This ingredient mainly works behind the scenes and helps with:

On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.

One thing worth knowing is that Disodium EDTA has been shown to be a mild penetration enhancer. It can help other ingredients absorb into skin more effectively which can be a double-edged sword (great for actives, but can also make the active too strong if you have sensitive skin).

Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.

You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.

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.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

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. 02Triethylhexanoin
  3. 03Cyclopentasiloxane
  4. 04Cetearyl Alcohol
  5. 05Cyclohexasiloxane
  6. 06Ceteareth-20
  7. 07Polymethyl Methacrylate
  8. 08Ceteareth-33
  9. 09Caprylic/Capric Triglyceride
  10. 10Ammonium Acryloyldimethyltaurate/Vp Copolymer
  11. 11Oenothera Biennis Oil
  12. 12Phenoxyethanol
  13. 13Benzoic Acid
  14. 14Disodium EDTA
  15. 15Retinal
  16. 16Tocopheryl Glucoside
  17. 17Oleoyl Dipeptide-15
  18. 18Mica
  19. 19Sodium Hydroxide
  20. 20Silica
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side