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The Ordinary Glycolic Acid 7% Toning Solution Versus The INKEY List Glycolic Acid Exfoliating Scalp Scrub

The Ordinary Glycolic Acid 7% Toning Solution Versus The INKEY List Glycolic Acid Exfoliating Scalp Scrub This smoothing toner is formulated around Glycolic Acid to refine skin texture and brighten dull-looking skin. What's inside Key Ingredients Benefits Conc

The Ordinary Glycolic Acid 7% Toning Solution Versus The INKEY List Glycolic Acid Exfoliating Scalp Scrub

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycolic Acid

Rosa Damascena Flower Water

Centaurea Cyanus Flower Water

Aloe Barbadensis Leaf Water

Propanediol

Glycerin

Triethanolamine

Aminomethyl Propanol

Panax Ginseng Root Extract

Tasmannia Lanceolata Fruit/Leaf Extract

Aspartic Acid

Alanine

Glycine

Serine

Valine

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Glutamic Acid

Arginine

PCA

Sodium PCA

Sodium Lactate

Fructose

Glucose

Sucrose

Urea

Hexyl Nicotinate

Dextrin

Citric Acid

Polysorbate 20

Gellan Gum

Trisodium Ethylenediamine Disuccinate

Sodium Chloride

Hexylene Glycol

Potassium Sorbate

Sodium Benzoate

1,2-Hexanediol

Caprylyl Glycol

Water, Glycolic Acid, Rosa Damascena Flower Water, Centaurea Cyanus Flower Water, Aloe Barbadensis Leaf Water, Propanediol, Glycerin, Triethanolamine, Aminomethyl Propanol, Panax Ginseng Root Extract, Tasmannia Lanceolata Fruit/Leaf Extract, Aspartic Acid, Alanine, Glycine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Glutamic Acid, Arginine, PCA, Sodium PCA, Sodium Lactate, Fructose, Glucose, Sucrose, Urea, Hexyl Nicotinate, Dextrin, Citric Acid, Polysorbate 20, Gellan Gum, Trisodium Ethylenediamine Disuccinate, Sodium Chloride, Hexylene Glycol, Potassium Sorbate, Sodium Benzoate, 1,2-Hexanediol, Caprylyl Glycol

Hydrogenated Castor Oil

PEG-40 Hydrogenated Castor Oil

Betaine

Sodium Hydroxide

Polyquaternium-10

Phenoxyethanol

Benzyl Alcohol

Alpha-Glucan Oligosaccharide

Citronellyl Methylcrotonate

Panthenol

Ethylhexylglycerin

Dehydroacetic Acid

Mannitol

Tetraselmis Suecica Extract

Lactic Acid

Potassium Benzoate

Water, Glycolic Acid, Propanediol, Hydrogenated Castor Oil, PEG-40 Hydrogenated Castor Oil, Betaine, Glycerin, Sodium Hydroxide, Polyquaternium-10, Phenoxyethanol, Benzyl Alcohol, Alpha-Glucan Oligosaccharide, Citronellyl Methylcrotonate, Panthenol, Ethylhexylglycerin, Dehydroacetic Acid, Mannitol, Trisodium Ethylenediamine Disuccinate, Sodium Benzoate, Tetraselmis Suecica Extract, Lactic Acid, Potassium Benzoate

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.

Glycolic Acid is arguably the most famous alpha hydroxy acid (AHA) with tons of research backing its benefits.

It is found naturally in sugar cane but the form used in skincare is usually synthetic for purity and stability.

Glycolic acid removes the top layer of dead skin cells to allow newer and fresher ones to emerge.

AHAs work by breaking down the structural “glue” that holds old skin cells in place. When that buildup is gone, your skin can renew itself more efficiently.

Research also shows glycolic acid stimulates collagen production, helping to firm and thicken the skin over time. This is one of its biggest advantages over other AHAs.

Overall, glycolic acid helps with:

Fun fact: Glycolic acid boosts skin hydration by helping it produce molecules that increase hyaluronic acid naturally.

To work best, glycolic acid products should have a pH between 3-4 (that’s where exfoliation is most effective but still gentle on skin).

The pH and concentration of a product are key to its effectiveness:

It is normal to feel a slight stinging sensation when using glycolic acid. This usually fades as your skin adjusts.

Because glycolic acid has the smallest molecular size in the AHA family, it can penetrate deeper, which enhances its effectiveness but also makes it more likely to irritate sensitive skin.

If your skin is very sensitive or prone to rosacea, glycolic acid may be too strong; in that case, try milder options like lactic acid or a PHA instead.

Recent studies suggest glycolic acid might even help protect against UV damage. But don’t skip sunscreen! Freshly exfoliated skin is more sensitive to the sun.

Glycolic acid is a skincare superstar. It smooths, brightens, hydrates, and firms the skin. Unless you’re highly sensitive, it’s well worth adding to your routine.

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 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.

Trisodium Ethylenediamine Disuccinate is used to help stabilize a product.

It is a chelating agent, meaning it helps prevent metal ions from binding to other ingredients. This prevents unwanted reactions in products. Metal ions can come into a product via the water ingredient. They are found in trace amounts and are not known to be harmful.

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. 03Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.
  4. 04Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.
  5. 05In practice, that translates to a long shelf life and a consistently elegant skin feel.
  6. 06While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.
  7. 07Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
  8. 08This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  9. 09This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures…
  10. 10Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  11. 11The 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 …
  12. 12Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  13. 13Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  14. 14Topically, glycerin does several things at once:
  15. 15Your 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.
  16. 16Aquaporin-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.
  17. 17This 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.
  18. 18Just know very high concentrations (>40%) can feel tacky in low humidity.
  19. 19Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  20. 20Sorbitan Isostearate is an emulsifer. It is created from isostearic acid and sorbitol.
Source · skinsort.com
02

Product index

Related product references

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Source: incidecoder.comView reference →
03

Comparison edit

Read side by side