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K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo Versus L'Oréal Professionnel Absolut Repair Molecular Repair Leave In Mask

K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo Versus L'Oréal Professionnel Absolut Repair Molecular Repair Leave In Mask What's inside Key Ingredients No key ingredients Benefits Concerns Ingredients Side-by-side Water Sodium C14-16 Olefin Sulfonate Cocamido

By Peptide Skincare & Beauty Editorial TeamPublished

K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo Versus L'Oréal Professionnel Absolut Repair Molecular Repair Leave In Mask

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Sodium C14-16 Olefin Sulfonate

Cocamidopropyl Hydroxysultaine

Salicylic Acid

Charcoal Powder

Sh-Oligopeptide-78

Panthenol

Glycerin

Sodium Phytate

Guar Hydroxypropyltrimonium Chloride

Caprylyl Glycol

Caprylhydroxamic Acid

Citric Acid

Potassium Hydroxide

Sodium Hydroxide

Parfum

Benzyl Salicylate

Limonene

Water, Sodium C14-16 Olefin Sulfonate, Cocamidopropyl Hydroxysultaine, Salicylic Acid, Charcoal Powder, Sh-Oligopeptide-78, Panthenol, Glycerin, Sodium Phytate, Guar Hydroxypropyltrimonium Chloride, Caprylyl Glycol, Caprylhydroxamic Acid, Citric Acid, Potassium Hydroxide, Sodium Hydroxide, Parfum, Benzyl Salicylate, Limonene

Isopropyl Myristate

Dimethicone

Amodimethicone

Triethanolamine

Phenoxyethanol

Carbomer

Polyquaternium-4

Potato Starch Modified

Hydroxypropyl Guar

Behentrimonium Chloride

Arginine

Trideceth-6

Isopropyl Alcohol

Cetrimonium Chloride

Linalool

Glycine

Serine

Tyrosine

Glutamic Acid

Coumarin

Benzyl Alcohol

Benzyl Benzoate

Alpha-Isomethyl Ionone

Water, Isopropyl Myristate, Dimethicone, Amodimethicone, Triethanolamine, Phenoxyethanol, Carbomer, Polyquaternium-4, Potato Starch Modified, Hydroxypropyl Guar, Behentrimonium Chloride, Arginine, Trideceth-6, Isopropyl Alcohol, Cetrimonium Chloride, Linalool, Glycine, Serine, Tyrosine, Citric Acid, Glutamic Acid, Coumarin, Benzyl Alcohol, Benzyl Benzoate, Alpha-Isomethyl Ionone, Parfum

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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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.

Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.

For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.

The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.

For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.

One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.

Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.

Parfum can also be used to mask or cover an unpleasant scent.

The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.

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.

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. 03Benzoic Acid is an organic acid that shows up in cosmetics as a preservative. It helps keep a product from spoiling by holding back the growth of yeast, mold, and some bacteria.
  4. 04This ingredient also functions as a fragrance ingredient that helps mask the unpleasant scent of other ingredients.
  5. 05The way it works is worth understanding; benzoic acid works when the formula is acidic. It is able to sneak into a microbe's cell and mess up how it functions to stop it from growing in an acidic product.
  6. 06However, the acid switches to an inactive form and stops working if a product isn't acidic enough (above ~5 pH). This is why you'll often see it in low pH products or teamed up with other preservatives to cover the gap.
  7. 07Safety wise, it's one of the better studied preservatives out there.
  8. 08The Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe for use in cosmetic formulations at concentrations up to 5%.
  9. 09A large international review found this ingredient had no effects on the human body and had low irritation potential.
  10. 10Just so you know, real world use is usually much lower than the 5% ceiling (usually 1% of less).
  11. 11The EU caps it at 2.5% in rinse-off products, 1.7% in oral care, and 0.5% in leave-on products.
  12. 12One thing worth mentioning (it's nothing to worry about): some people get a little stinging or flushing where they apply it. This isn't a true allergy; it's a temporary and harmless reaction. This is the same kind of mild tingle you might notice fro…
  13. 13Caprylhydroxamic Acid is a chelating agent that helps cosmetics stay fresh, stable, and consistent over time.
  14. 14Chelating agents help prevent metal ions from binding to other ingredients. This helps prevent unwanted reactions and effects from using the product. It also helps prevent the growth of unwanted microbes in products that contain water.
  15. 15Caprylhydroxamic Acid is often used with natural antimicrobial products as an alternative to preservatives.
  16. 16Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  17. 17Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  18. 18Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  19. 19Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  20. 20Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
Source · skinsort.com ⟶
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