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Skin science article

Neutrogena Hydro Boost City Shield Water Gel SPF 25 Versus Paula's Choice Clinical Ultra-Rich Moisturizer

Neutrogena Hydro Boost City Shield Water Gel SPF 25 Versus Paula's Choice Clinical Ultra-Rich Moisturizer This barrier-repair day moisturizer is formulated around Tocopheryl Acetate and Sodium Hyaluronate to strengthen the skin barrier and hydrate skin. This b

Neutrogena Hydro Boost City Shield Water Gel SPF 25 Versus Paula's Choice Clinical Ultra-Rich Moisturizer

This barrier-repair day moisturizer is formulated around Tocopheryl Acetate and Sodium Hyaluronate to strengthen the skin barrier and hydrate skin.

This barrier-repair moisturizer is formulated around Butyrospermum Parkii Butter Unsaponifiables and Ceramide NP to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Butyl Methoxydibenzoylmethane 2%

Homosalate 4%

Ethylhexyl Salicylate 4%

Octocrylene 2%

Water

Glycerin

Caprylyl Methicone

Methyl Methacrylate Crosspolymer

Propylene Glycol

Sodium Acryloyldimethyltaurate/Vp Crosspolymer

Phenoxyethanol

Glyceryl Stearate

Chlorphenesin

Tocopheryl Acetate

Sodium Hyaluronate

Disodium EDTA

Ethylhexylglycerin

Parfum

Sodium Hydroxide

Blue 1 Lake

CI 16035

Butyl Methoxydibenzoylmethane 2%, Homosalate 4%, Ethylhexyl Salicylate 4%, Octocrylene 2%, Water, Glycerin, Caprylyl Methicone, Methyl Methacrylate Crosspolymer, Propylene Glycol, Sodium Acryloyldimethyltaurate/Vp Crosspolymer, Phenoxyethanol, Glyceryl Stearate, Chlorphenesin, Tocopheryl Acetate, Sodium Hyaluronate, Disodium EDTA, Ethylhexylglycerin, Parfum, Sodium Hydroxide, Blue 1 Lake, CI 16035

Butyrospermum Parkii Butter Unsaponifiables

Caprylic/Capric Triglyceride

Glyceryl Stearate Se

Olea Europaea Fruit Oil

Dimethicone

Stearic Acid

Mangifera Indica Seed Butter

Cetyl Alcohol

Cocos Nucifera Fruit Extract

Ceramide NP

Ceramide AP

Ceramide EOP

Sphingolipids

Phospholipids

Phytosphingosine

Squalene

Cholesterol

Tocopherol

Simmondsia Chinensis Seed Oil

Persea Gratissima Oil

Glycine Soja Oil

Oryza Sativa Bran Extract

Avena Sativa Kernel Extract

Panthenol

Ascorbyl Palmitate

Beta-Sitosterol

Hydrogenated Vegetable Glycerides Citrate

Sodium Lauroyl Lactylate

Xanthan Gum

Carbomer

Water, Butyrospermum Parkii Butter Unsaponifiables, Caprylic/Capric Triglyceride, Glyceryl Stearate Se, Olea Europaea Fruit Oil, Dimethicone, Stearic Acid, Glyceryl Stearate, Mangifera Indica Seed Butter, Cetyl Alcohol, Cocos Nucifera Fruit Extract, Ceramide NP, Ceramide AP, Ceramide EOP, Sphingolipids, Phospholipids, Phytosphingosine, Squalene, Cholesterol, Tocopherol, Simmondsia Chinensis Seed Oil, Persea Gratissima Oil, Glycine Soja Oil, Oryza Sativa Bran Extract, Avena Sativa Kernel Extract, Glycerin, Panthenol, Ascorbyl Palmitate, Beta-Sitosterol, Hydrogenated Vegetable Glycerides Citrate, Propylene Glycol, Sodium Lauroyl Lactylate, Xanthan Gum, Carbomer, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol

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.

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.

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.

Propylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.

As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

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.

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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. 03Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  4. 04Despite 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.
  5. 05It plays several roles in a formula:
  6. 06Typical 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.
  7. 07Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  8. 08However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  9. 09Cetearyl 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.
  10. 10Here'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.
  11. 11Remember 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.
  12. 12This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.
  13. 13A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.
  14. 14Disodium EDTA is a chelating agent. It grabs onto and deactivates metal ions that sneak into your products from water, packaging, or air.
  15. 15This ingredient mainly works behind the scenes and helps with:
  16. 16On top of that, this ingredient can counteract the effects of hard water by binding to the minerals in it.
  17. 17One 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 st…
  18. 18Clinical patch testing showed no significant skin irritation at typical use concentrations and minimal dermal absorption.
  19. 19You'll most likely see this ingredient near the end of an ingredient list. It's typically found in concentrations less than 1%.
  20. 20Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
Source · skinsort.com
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Related product references

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Comparison edit

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