Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Hask Tea Tree Oil & Rosemary Invigorating Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo

Hask Tea Tree Oil & Rosemary Invigorating Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Water Sodium C14-16 Olefin Sulfonate Cocamide Mea Cocamidopropyl Betaine Glycerin

Hask Tea Tree Oil & Rosemary Invigorating Shampoo Versus K18 Hair PEPTIDE PREP™ Clarifying Detox Shampoo

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Sodium C14-16 Olefin Sulfonate

Cocamide Mea

Cocamidopropyl Betaine

Glycerin

Glycol Distearate

Melaleuca Alternifolia Leaf Oil

Rosmarinus Officinalis Leaf Oil

Menthol

Panthenol

Polyquaternium-68

Polyquaternium-7

Ethylhexylglycerin

PEG-150 Distearate

Guar Hydroxypropyltrimonium Chloride

Sodium Hydroxide

Phenoxyethanol

Hydroxypropyl Methylcellulose

Sodium Benzoate

Magnesium Nitrate

Sodium Chloride

Methylisothiazolinone

Methylchloroisothiazolinone

Citric Acid

Magnesium Chloride

Parfum

Limonene

Linalool

Water, Sodium C14-16 Olefin Sulfonate, Cocamide Mea, Cocamidopropyl Betaine, Glycerin, Glycol Distearate, Melaleuca Alternifolia Leaf Oil, Rosmarinus Officinalis Leaf Oil, Menthol, Panthenol, Polyquaternium-68, Polyquaternium-7, Ethylhexylglycerin, PEG-150 Distearate, Guar Hydroxypropyltrimonium Chloride, Sodium Hydroxide, Phenoxyethanol, Hydroxypropyl Methylcellulose, Sodium Benzoate, Magnesium Nitrate, Sodium Chloride, Methylisothiazolinone, Methylchloroisothiazolinone, Citric Acid, Magnesium Chloride, Parfum, Limonene, Linalool

Cocamidopropyl Hydroxysultaine

Salicylic Acid

Charcoal Powder

Sh-Oligopeptide-78

Sodium Phytate

Caprylyl Glycol

Caprylhydroxamic Acid

Potassium 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.

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.

This ingredient is derived from guar gum. It is a skin conditioning agent that creates a thin, breathable film to reduce water loss during cleansing.

This leaves the skin feeling soft rather than stripped and also contributes to a creamier lather.

Due to the large molecule size, this ingredient is unlikely to penetrate skin.

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.

Sodium C14-16 Olefin Sulfonate is a surfactant that helps water and oil mix so that dirt, sweat, sebum, and sunscreen can rinse away easily. It's not technically a sulfate, but behaves similarly in formulas.

What it does:

Sodium C14-16 Olefin Sulfonate is a strong cleansing surfactant and is much stronger than many mild cleansers. Because it works deeply, it can disrupt the skin's barrier. This can lead to dryness or irritation for those with sensitive skin.

Compared to gentler surfactants, it's effective but more likely to dry or irritate if not balanced with soothing ingredients.

CIR considers sodium α-olefin sulfonates (including C14-16) to be safe for use in rinse-off products when properly formulated. It is poorly absorbed through normal skin but absorption increases if the skin barrier is already damaged.

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.

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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. 03Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
  4. 04There are two forms of panthenol: D and L.
  5. 05D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.
  6. 06Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):
  7. 07Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.
  8. 08This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.
  9. 09Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
  10. 10This ingredient is also referred to as pro-vitamin B5.
  11. 11Salicylic 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, …
  12. 12Unlike 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.
  13. 13Salicylic 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.
  14. 14Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
  15. 15It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.
  16. 16While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
  17. 17If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.
  18. 18Sodium Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.
  19. 19Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.
  20. 20Water. 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.
Source · skinsort.com
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