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Olaplex No. 4C Bond Maintenance Clarifying Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo

Olaplex No. 4C Bond Maintenance Clarifying Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo What's inside Key Ingredients No key ingredients Benefits Concerns Ingredients Side-by-side Water Sodium Lauroyl Methyl Isethionate Cocamidopropyl Hydroxy

Olaplex No. 4C Bond Maintenance Clarifying Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Sodium Lauroyl Methyl Isethionate

Cocamidopropyl Hydroxysultaine

Sodium Lauroyl Glutamate

Coco-Betaine

Disodium Laureth Sulfosuccinate

Acrylates Copolymer

Cocamidopropyl Betaine

Cocamidopropylamine Oxide

Sodium Methyl Oleoyl Taurate

Decyl Glucoside

Bis-Aminopropyl Diglycol Dimaleate

Sodium Lauryl Sulfoacetate

Phenoxyethanol

Coco-Glucoside

Lauryl Glucoside

Chlorphenesin

Panthenol

Trisodium Ethylenediamine Disuccinate

Diethylhexyl Succinate

Sodium Benzoate

Polyquaternium-11

Benzoic Acid

Sodium PCA

Pentasodium Triphosphate

Sodium Lactate

Arginine

Aspartic Acid

PCA

Citric Acid

Glycine

Alanine

Serine

Valine

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Parfum

Citral

Hexyl Cinnamal

Limonene

Water, Sodium Lauroyl Methyl Isethionate, Cocamidopropyl Hydroxysultaine, Sodium Lauroyl Glutamate, Coco-Betaine, Disodium Laureth Sulfosuccinate, Acrylates Copolymer, Cocamidopropyl Betaine, Cocamidopropylamine Oxide, Sodium Methyl Oleoyl Taurate, Decyl Glucoside, Bis-Aminopropyl Diglycol Dimaleate, Sodium Lauryl Sulfoacetate, Phenoxyethanol, Coco-Glucoside, Lauryl Glucoside, Chlorphenesin, Panthenol, Trisodium Ethylenediamine Disuccinate, Diethylhexyl Succinate, Sodium Benzoate, Polyquaternium-11, Benzoic Acid, Sodium PCA, Pentasodium Triphosphate, Sodium Lactate, Arginine, Aspartic Acid, PCA, Citric Acid, Glycine, Alanine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Parfum, Citral, Hexyl Cinnamal, Limonene

Sodium C14-16 Olefin Sulfonate

Salicylic Acid

Charcoal Powder

Sh-Oligopeptide-78

Glycerin

Sodium Phytate

Guar Hydroxypropyltrimonium Chloride

Caprylyl Glycol

Caprylhydroxamic Acid

Potassium Hydroxide

Sodium Hydroxide

Benzyl Salicylate

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

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.

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.

Cocamidopropyl Hydroxysultaine is a synthetic cleansing agent, though it is derived from coconut oil.

It is used to enhance the texture of products by boosting lather and thickening the texture. As a cleanser, Cocamidopropyl Hydroxysultaine is mild.

Limonene is a fragrance that adds scent and taste to a formulation.

It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".

Limonene acts as an antioxidant, meaning it helps neutralize free radicals.

When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.

The term '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.

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.

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!

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. 03Limonene is a fragrance that adds scent and taste to a formulation.
  4. 04It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".
  5. 05Limonene acts as an antioxidant, meaning it helps neutralize free radicals.
  6. 06When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.
  7. 07The term '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, the…
  8. 08Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
  9. 09Also 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.
  10. 10For 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 regul…
  11. 11The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
  12. 12For 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.
  13. 13One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
  14. 14Depending 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.
  15. 15Parfum can also be used to mask or cover an unpleasant scent.
  16. 16The 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.
  17. 17Sh-Oligopeptide-78 is a peptide.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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