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Naturium Vegan Lactic Acid Emulsion 5% Versus The INKEY List Lactic Acid Serum

Naturium Vegan Lactic Acid Emulsion 5% Versus The INKEY List Lactic Acid Serum This smoothing serum is formulated around Lactic Acid and 3-O-Ethyl Ascorbic Acid to refine skin texture and brighten dull-looking skin. This smoothing serum is formulated around La

Naturium Vegan Lactic Acid Emulsion 5% Versus The INKEY List Lactic Acid Serum

This smoothing serum is formulated around Lactic Acid and 3-O-Ethyl Ascorbic Acid to refine skin texture and brighten dull-looking skin.

This smoothing serum is formulated around Lactic Acid to refine skin texture and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Caprylic/Capric Triglyceride

Helianthus Annuus Seed Oil

Glyceryl Stearate

Lactic Acid

Cetyl Alcohol

Glycerin

3-O-Ethyl Ascorbic Acid

Niacinamide

Glyceryl Stearate Citrate

Aloe Barbadensis Leaf Juice

Bisabolol

Tocopheryl Acetate

Evodia Rutaecarpa Fruit Extract

Propanediol

Tocopherol

1,2-Hexanediol

Caprylyl Glycol

Xanthan Gum

Sodium Hydroxide

Water, Caprylic/Capric Triglyceride, Helianthus Annuus Seed Oil, Glyceryl Stearate, Lactic Acid, Cetyl Alcohol, Glycerin, 3-O-Ethyl Ascorbic Acid, Niacinamide, Glyceryl Stearate Citrate, Aloe Barbadensis Leaf Juice, Bisabolol, Tocopheryl Acetate, Evodia Rutaecarpa Fruit Extract, Propanediol, Tocopherol, 1,2-Hexanediol, Caprylyl Glycol, Xanthan Gum, Sodium Hydroxide

PPG-26-Buteth-26

Sodium Hyaluronate

Phenoxyethanol

PEG-40 Hydrogenated Castor Oil

Ethylhexylglycerin

Trisodium Ethylenediamine Disuccinate

Agastache Mexicana Flower/Leaf/Stem Extract

Water, Lactic Acid, Propanediol, Glycerin, Sodium Hydroxide, PPG-26-Buteth-26, Sodium Hyaluronate, Phenoxyethanol, PEG-40 Hydrogenated Castor Oil, Ethylhexylglycerin, Trisodium Ethylenediamine Disuccinate, Agastache Mexicana Flower/Leaf/Stem Extract

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.

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Read more about some other popular AHA's here:

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.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

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 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 Olivate is a plant-derived emulsifier and texture enhancer. It helps keep the oil and water phases from separating so your formulas stay stable.
  4. 04You'll likely see it combined with Sorbitan Olivate (together sold as the trade name Olivem 1000). This combination generates a liquid crystal structure that closely resemble the lipid organization of the stratum corneum.
  5. 05These "skin-like" liquid crystals improve skin barrier integrity and promote the delivery of actives into the skin.
  6. 06This ingredient is well-tolerated and has no significant sensitization data.
  7. 07Because it is derived from the fatty acids in olive oil, this ingredient may not be fungal acne safe.
  8. 08Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  9. 09The 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 …
  10. 10Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  11. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your 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.
  14. 14Aquaporin-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.
  15. 15This 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.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  19. 19It 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.
  20. 20On 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.
Source · skinsort.com
02

Product index

Related product references

Product

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The Inkey List Advanced Retinal Serum The Inkey List Advanced Retinal Serum ingredients explained: Aqua (Water), Glycerin, Caprylic/Capric Triglyceride, Dicaprylyl Carbonate, Polyglyceryl-6…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side