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The Ordinary Hyaluronic Acid 2% + B5 Serum Versus The INKEY List Collagen Booster

The Ordinary Hyaluronic Acid 2% + B5 Serum Versus The INKEY List Collagen Booster This hydrating serum is formulated around Sodium Hyaluronate and Panthenol to hydrate skin and strengthen the skin barrier. This anti-aging serum is formulated around Palmitoyl T

The Ordinary Hyaluronic Acid 2% + B5 Serum Versus The INKEY List Collagen Booster

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

This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 and Palmitoyl Tripeptide-1 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Sodium Hyaluronate

Propanediol

Pentylene Glycol

Hydrolyzed Hyaluronic Acid

Sodium Hyaluronate Crosspolymer

Phospholipids

Sphingolipids

Panthenol

Ahnfeltiopsis Concinna Extract

Glycerin

Polysorbate 20

Citric Acid

Sodium Citrate

P-Anisic Acid

Tocopherol

Trisodium Ethylenediamine Disuccinate

Caprylyl Glycol

Ethoxydiglycol

Ethylhexylglycerin

Hexylene Glycol

Phenoxyethanol

Chlorphenesin

Water, Sodium Hyaluronate, Propanediol, Pentylene Glycol, Hydrolyzed Hyaluronic Acid, Sodium Hyaluronate Crosspolymer, Phospholipids, Sphingolipids, Panthenol, Ahnfeltiopsis Concinna Extract, Glycerin, Polysorbate 20, Citric Acid, Sodium Citrate, P-Anisic Acid, Tocopherol, Trisodium Ethylenediamine Disuccinate, Caprylyl Glycol, Ethoxydiglycol, Ethylhexylglycerin, Hexylene Glycol, Phenoxyethanol, Chlorphenesin

Butylene Glycol

Hydroxyethylcellulose

Disodium EDTA

Leuconostoc/Radish Root Ferment Filtrate

Carbomer

Hyaluronic Acid

Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine

Palmitoyl Dipeptide-5 Diaminohydroxybutyrate

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellulose, Disodium EDTA, Leuconostoc/Radish Root Ferment Filtrate, Carbomer, Hyaluronic Acid, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Palmitoyl Dipeptide-5 Diaminohydroxybutyrate, Polysorbate 20, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

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.

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.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

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. 03Aloe Barbadensis Leaf Juice is the filtered, stabilized liquid pressed from the inner gel of the aloe vera leaf.
  4. 04In cosmetics, it shows up as either soothing active or a water-replacement base. It is roughly 98-99% water and the last 1-2% is an interesting mix of polysaccharides, amino acids, vitamins, minerals, and enzymes.
  5. 05The polysaccharides do most of the work: they bind water at the skin surface for a light, non-greasy hydration boost. And one of the polysaccharides, glycomannan, is linked to fibroblast stimulation + collagen synthesis. This is also why aloe has su…
  6. 06This ingredient is also calming with anti-inflammatory and mild antimicrobial activity, making it a great pick for sensitive, irritated, or post-sun skin.
  7. 07Realistic expectations matter though; the solid evidence is mostly limited to hydration, soothing, and wound support. Deeper claims about anti-aging or sun protection are not well backed, and science reviews note it does not prevent radiation-induce…
  8. 08Because it plays well with almost everything, it's commonly used as a base alongside other actives like niacinamide or vitamin C.
  9. 09Typical usage concentrations range from 0.5% (where hydration benefits already show up) all the way to 90%+ (where it replaces water as the main base).
  10. 10The safety for this ingredient is well-establish as well. Overall, this is a great supporting ingredient for those who want a boost in hydration.
  11. 11Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.
  12. 12This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.
  13. 13As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.
  14. 14The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.
  15. 15This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.
  16. 16It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.
  17. 17Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.
  18. 18At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.
  19. 19Dehydroacetic Acid is a synthetic preservative that keeps your products safe from microbes.
  20. 20As an organic acid, it penetrates microbial cell walls and disrupts cellular metabolism. This makes it effective against bacteria, yeast, and mold.
Source · skinsort.com
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Product index

Related product references

Product

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Source: incidecoder.comView reference →
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Comparison edit

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