Peptide Skincare & BeautySkin science and ingredient guides

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The INKEY List Peptide Moisturizer Versus The INKEY List Collagen Peptide Serum

The INKEY List Peptide Moisturizer Versus The INKEY List Collagen Peptide Serum This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture. What's inside Key Ingredients Benefits Concerns Ingredie

The INKEY List Peptide Moisturizer Versus The INKEY List Collagen Peptide Serum

This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Caprylic/Capric Triglyceride

Glycerin

C12-15 Alkyl Benzoate

Cetearyl Alcohol

Glyceryl Stearate Se

Betaine

Butylene Glycol

Phenoxyethanol

Benzyl Alcohol

Carbomer

Butyrospermum Parkii Butter

Sodium Stearoyl Glutamate

Sodium Hydroxide

Ethylhexylglycerin

Sodium Gluconate

Tocopheryl Acetate

Dehydroacetic Acid

Hydrogenated Lecithin

Phenethyl Alcohol

Acetyl Hexapeptide-37

Maltodextrin

Pentapeptide-48

Water, Caprylic/Capric Triglyceride, Glycerin, C12-15 Alkyl Benzoate, Cetearyl Alcohol, Glyceryl Stearate Se, Betaine, Butylene Glycol, Phenoxyethanol, Benzyl Alcohol, Carbomer, Butyrospermum Parkii Butter, Sodium Stearoyl Glutamate, Sodium Hydroxide, Ethylhexylglycerin, Sodium Gluconate, Tocopheryl Acetate, Dehydroacetic Acid, Hydrogenated Lecithin, Phenethyl Alcohol, Acetyl Hexapeptide-37, Maltodextrin, Pentapeptide-48

Propanediol

Hydroxyethylcellulose

Sodium Phytate

Citric Acid

Leuconostoc/Radish Root Ferment Filtrate

Hyaluronic Acid

Sodium Lactate

Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine

Palmitoyl Dipeptide-5 Diaminohydroxybutyrate

Polysorbate 20

Polysorbate 60

Disodium Phosphate

Sodium Phosphate

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellulose, Sodium Phytate, Citric Acid, Leuconostoc/Radish Root Ferment Filtrate, Carbomer, Hyaluronic Acid, Sodium Lactate, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Palmitoyl Dipeptide-5 Diaminohydroxybutyrate, Polysorbate 20, Polysorbate 60, Disodium Phosphate, Sodium Phosphate, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

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.

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.

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 Side-by-side

  1. 01Water
  2. 02Caprylic/Capric Triglyceride
  3. 03Glycerin
  4. 04C12-15 Alkyl Benzoate
  5. 05Cetearyl Alcohol
  6. 06Glyceryl Stearate Se
  7. 07Betaine
  8. 08Butylene Glycol
  9. 09Phenoxyethanol
  10. 10Benzyl Alcohol
  11. 11Carbomer
  12. 12Butyrospermum Parkii Butter
  13. 13Sodium Stearoyl Glutamate
  14. 14Sodium Hydroxide
  15. 15Ethylhexylglycerin
  16. 16Sodium Gluconate
  17. 17Tocopheryl Acetate
  18. 18Dehydroacetic Acid
  19. 19Hydrogenated Lecithin
  20. 20Phenethyl Alcohol
Source · skinsort.com
02

Product index

Related product references

Product

The Inky List Collagen Peptide Serum

The Inky List Collagen Peptide Serum The Inky List Collagen Peptide Serum ingredients explained: Water (Aqua/Eau), Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellul…

Source: incidecoder.comView reference →

Product

Madara Derma Collagen Peptide Serum

Madara Derma Collagen Peptide Serum Ingredients in Madara Derma Collagen Peptide Serum explained: benefits, concerns, and detailed analysis of 28 ingredients including Aloe Barbadensis Leaf…

Source: skinsort.comView reference →
03

Comparison edit

Read side by side