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Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum Versus L'Oreal Revitalift 1.5% Pure Hyaluronic Acid Serum

Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum Versus L'Oreal Revitalift 1.5% Pure Hyaluronic Acid Serum This hydrating serum is formulated around Sodium Hyaluronate to hydrate skin and strengthen the skin barrier. This hydrating serum is formulate

Kiehl's Ultra Pure High-Potency 1.5% Hyaluronic Acid Serum Versus L'Oreal Revitalift 1.5% Pure Hyaluronic Acid Serum

This hydrating serum is formulated around Sodium Hyaluronate to hydrate skin and strengthen the skin barrier.

This hydrating serum is formulated around Sodium Hyaluronate and Dipeptide Diaminobutyroyl Benzylamide Diacetate to hydrate skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Sodium Hyaluronate

Phenoxyethanol

Chlorphenesin

Tetrasodium Glutamate Diacetate

Citric Acid

Water, Glycerin, Sodium Hyaluronate, Phenoxyethanol, Chlorphenesin, Tetrasodium Glutamate Diacetate, Citric Acid

Hydroxyethylpiperazine Ethane Sulfonic Acid

PEG-60

Hydrogenated Castor Oil

Secale Cereale Seed Extract

Calcium Pantothenate

Dipeptide Diaminobutyroyl Benzylamide Diacetate

Ascorbyl Glucoside

Disodium EDTA

Pentylene Glycol

Water, Glycerin, Hydroxyethylpiperazine Ethane Sulfonic Acid, Sodium Hyaluronate, PEG-60, Hydrogenated Castor Oil, Secale Cereale Seed Extract, Calcium Pantothenate, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Ascorbyl Glucoside, Disodium EDTA, Pentylene Glycol, Phenoxyethanol, Chlorphenesin

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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.

Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.

Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.

Chlorphenesin is soluble in both water and glycerin.

Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.

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 Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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. 03Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration.
  4. 04Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.
  5. 05Some studies suggest betaine may support making skin tone more even.
  6. 06Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.
  7. 07Betaine is also known as trimethylglycine.
  8. 08Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  9. 09Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  10. 10Though 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.
  11. 11Carbomer 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.
  12. 12Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  13. 13It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  14. 14Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  15. 15A 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.
  16. 16Dipropylene Glycol is a synthetically created humectant, stabilizer, and solvent.
  17. 17This ingredient helps:
  18. 18Dipropylene glycol is technically an alcohol, but it belongs to the glycol family (often considered part of the ‘good’ alcohols). This means it is hydrating and gentle on skin unlike drying solvent alcohols like denatured alcohol.
  19. 19As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.
  20. 20Studies show Dipropylene Glycol is considered safe to use in skincare.
Source · skinsort.com
02

Product index

Related product references

Product

Dr. Davey Hyaluronic Acid Serum

Dr. Davey Hyaluronic Acid Serum Dr. Davey Hyaluronic Acid Serum ingredients explained: Aqua, Butylene Glycol, PEG-40 Hydrogenated Castor Oil, Jojoba Oil, Ascorbic Acid, Glycerin, Tocopherol…

Source: incidecoder.comView reference →

Product

Dr. Brenner Hyaluronic Acid Serum

Dr. Brenner Hyaluronic Acid Serum Dr. Brenner Hyaluronic Acid Serum ingredients explained: Water, Calcium Pantothenate (Vitamin B5), Sodium Hyaluronate (Hyaluronic Acid), Phenoxyethanol Sho…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side

04

Ask the journal

Related questions

01When and How to Use Hyaluronic Acid in Your Routine

Products with hyaluronic acid can be used in the morning or at night (or both!). Applying the hydrating ingredient at night will restore your skin’s resilience while you sleep, and applying it in the morning will leave your skin feeling plump, hydrated and ready for makeup. Hyaluronic acid is great at providing topical hydration when it’s introduced into a balanced skincare routine. According to Dr. King, it’s important to pair your hyaluronic acid products with an emollient or occlusive moisturizer to lock in hydration.

Source · www.skincare.com
02How to Apply Face Serums

Skincare rules can get confusing, but when it comes to application the general rule of thumb is to pay attention to the product’s consistency. “Apply the lightest, thinnest product first and the heaviest, and more dense products last, since thinner products can’t penetrate thicker products,”says Dr. Lewis. After cleansing the face and following up with a toner, let the skin dry before using a serum. You can layer different serums on top of each other or opt for a product that has a precise mix of multiple hero ingredients, such as hyaluronic acid and vitamin C.

Source · www.skincare.com