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The INKEY List Peptide Moisturizer Versus DR's Secret Emulsion A6

The INKEY List Peptide Moisturizer Versus DR's Secret Emulsion A6 This hydrating emulsion is formulated around Squalane and Panthenol to hydrate skin and strengthen the skin barrier. What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Wate

The INKEY List Peptide Moisturizer Versus DR's Secret Emulsion A6

This hydrating emulsion is formulated around Squalane and Panthenol to hydrate skin and strengthen the skin barrier.

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

Cyclopentasiloxane

Cyclohexasiloxane

Squalane

Glyceryl Stearate

Bis-PEG-18 Methyl Ether Dimethyl Silane

Polysorbate 60

PEG-100 Stearate

Panthenol

Sorbitan Sesquioleate

Caprylyl Glycol

Vitis Vinifera Seed Oil

Citrus Limon Peel Oil

Lactobacillus

Lactobacillus/Punica Granatum Fruit Ferment Extract

Polyacrylate-13

Glyceryl Polyacrylate

Triethanolamine

Polyisobutene

Disodium EDTA

Polysorbate 20

Sorbitan Isostearate

Apium Graveolens Root Extract

Brassica Oleracea Capitata Leaf Extract

Brassica Oleracea Italica Extract

Brassica Rapa Leaf Extract

Daucus Carota Sativa Root Extract

Oryza Sativa Extract

Solanum Lycopersicum Fruit Extract

Pentylene Glycol

PEG-40 Hydrogenated Castor Oil

PPG-26-Buteth-26

1,2-Hexanediol

Lecithin

Sodium Phosphate

Copper Tripeptide-1

Palmitoyl Tripeptide-1

Oligopeptide-1

Water, Butylene Glycol, Glycerin, Cyclopentasiloxane, Cyclohexasiloxane, Squalane, Glyceryl Stearate, Bis-PEG-18 Methyl Ether Dimethyl Silane, Caprylic/Capric Triglyceride, Polysorbate 60, Cetearyl Alcohol, PEG-100 Stearate, Panthenol, Sorbitan Sesquioleate, Ethylhexylglycerin, Caprylyl Glycol, Vitis Vinifera Seed Oil, Citrus Limon Peel Oil, Lactobacillus, Lactobacillus/Punica Granatum Fruit Ferment Extract, Polyacrylate-13, Glyceryl Polyacrylate, Carbomer, Triethanolamine, Polyisobutene, Disodium EDTA, Polysorbate 20, Sorbitan Isostearate, Apium Graveolens Root Extract, Brassica Oleracea Capitata Leaf Extract, Brassica Oleracea Italica Extract, Brassica Rapa Leaf Extract, Daucus Carota Sativa Root Extract, Oryza Sativa Extract, Solanum Lycopersicum Fruit Extract, Pentylene Glycol, PEG-40 Hydrogenated Castor Oil, PPG-26-Buteth-26, 1,2-Hexanediol, Lecithin, Sodium Phosphate, Copper Tripeptide-1, Palmitoyl Tripeptide-1, Oligopeptide-1, Phenoxyethanol

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.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

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.

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 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. 03This ingredient is also known as shea butter. It is a plant-derived extract from the nuts of the Africa shea tree and one of the most well-studied emollients.
  4. 04Because it has a high concentration of fatty acids (primarily oleic, stearic, and linoleic) it is able to form a protective barrier on the skin's surface. This helps seal in moisture and prevents transepidermal water loss (TEWL).
  5. 05In vitro research found an increase in skin hydration by 58% and a decrease in TEWL by 37.8% after 24 hours of applying this ingredient (pretty impressive for a single ingredient!).
  6. 06Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
  7. 07Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
  8. 08While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
  9. 09This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
  10. 10Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.
  11. 11Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.
  12. 12In practice, that translates to a long shelf life and a consistently elegant skin feel.
  13. 13While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.
  14. 14Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.
  15. 15This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  16. 16This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures…
  17. 17Carbomer 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.
  18. 18Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  19. 19It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  20. 20Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
Source · skinsort.com
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Comparison edit

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