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The INKEY List Hyaluronic Acid Hydrating Hair Treatment Versus The INKEY List Salicylic Acid Exfoliating Scalp Treatment

The INKEY List Hyaluronic Acid Hydrating Hair Treatment Versus The INKEY List Salicylic Acid Exfoliating Scalp Treatment What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Water PEG-40 Hydrogenated Castor Oil Betaine Panthenol Phenoxyetha

The INKEY List Hyaluronic Acid Hydrating Hair Treatment Versus The INKEY List Salicylic Acid Exfoliating Scalp Treatment

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

PEG-40 Hydrogenated Castor Oil

Betaine

Panthenol

Phenoxyethanol

Polyquaternium-37

Citronellyl Methylcrotonate

Ethylhexylglycerin

Hydrolyzed Hyaluronic Acid

Trisodium Ethylenediamine Disuccinate

Lactic Acid

Sodium Hyaluronate

Water, PEG-40 Hydrogenated Castor Oil, Betaine, Panthenol, Phenoxyethanol, Polyquaternium-37, Citronellyl Methylcrotonate, Ethylhexylglycerin, Hydrolyzed Hyaluronic Acid, Trisodium Ethylenediamine Disuccinate, Lactic Acid, Sodium Hyaluronate

Propanediol

Salicylic Acid

Hexylene Glycol

Capryloyl Glycine

Sodium Hydroxide

Xylitylglucoside

Water, Propanediol, Salicylic Acid, Betaine, Panthenol, PEG-40 Hydrogenated Castor Oil, Phenoxyethanol, Polyquaternium-37, Hexylene Glycol, Capryloyl Glycine, Citronellyl Methylcrotonate, Sodium Hydroxide, Ethylhexylglycerin, Xylitylglucoside, Trisodium Ethylenediamine Disuccinate

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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.

Betaine 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.

Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.

Some studies suggest betaine may support making skin tone more even.

Fun 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.

Betaine is also known as trimethylglycine.

Citronellyl Methylcrotonate is a fragrance.

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.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

PEG-40 Hydrogenated Castor Oil is an emulsifier derived from castor oil.

As an emulsifying agent, it helps other ingredients like fragrances and fat-soluble vitamins dissolve cohesively.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

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.

We don't have a description for Polyquaternium-37 yet.

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!

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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. 03Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.
  4. 04This 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.
  5. 05As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.
  6. 06The 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.
  7. 07This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.
  8. 08It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.
  9. 09Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.
  10. 10At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.
  11. 11Cocamidopropyl Betaine is a fatty acid created by mixing similar compounds in coconut oil and dimethylaminopropylamine, a compound with two amino groups.
  12. 12This ingredient is a surfactant and cleanser. It helps gather the dirt, pollutants, and other impurities in your skin to be washed away. It also helps thicken a product and make the texture more creamy.
  13. 13Being created from coconut oil means Cocamidopropyl Betaine is hydrating for the skin.
  14. 14While Cocamidopropyl Betaine was believed to be an allergen, a study from 2012 disproved this. It found two compounds in unpure Cocamidopropyl Betaine to be the irritants: aminoamide and 3-dimethylaminopropylamine. High-grade and pure Cocamidopropyl…
  15. 15Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  16. 16The 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 …
  17. 17Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  18. 18Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, …
  19. 19Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.
  20. 20Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.
Source · skinsort.com
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Product index

Related product references

Product

The Inkey List Glucoside Serum

The Inkey List Glucoside Serum The Inkey List Glucoside Serum ingredients explained: Aqua, Glycerin, Sodium Carbomer, Benzyl Alcohol, Phenoxyethanol, Citric Acid, Tocopheryl Acetate, Dehydr…

Source: incidecoder.comView reference →
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Comparison edit

Read side by side