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Kiehl's Ultra Facial Moisturizer Versus The INKEY List Peptide Moisturizer

Kiehl's Ultra Facial Moisturizer Versus The INKEY List Peptide Moisturizer This day moisturizer is formulated around Squalene to hydrate skin. What's inside Key Ingredients Benefits Concerns Ingredients Side-by-side Water Propylene Glycol Dicaprylyl Ether Glyc

Kiehl's Ultra Facial Moisturizer Versus The INKEY List Peptide Moisturizer

This day moisturizer is formulated around Squalene to hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propylene Glycol

Dicaprylyl Ether

Glycerin

PEG-100 Stearate

Glyceryl Stearate

Squalene

Hydrogenated Polyisobutene

Phenoxyethanol

Sorbitan Oleate

Caprylyl Glycol

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Triethanolamine

Beeswax

Tocopherol

Disodium EDTA

Stearic Acid

Myristyl Alcohol

Prunus Amygdalus Dulcis Oil

Prunus Armeniaca Kernel Oil

Persea Gratissima Oil

Water, Propylene Glycol, Dicaprylyl Ether, Glycerin, PEG-100 Stearate, Glyceryl Stearate, Squalene, Hydrogenated Polyisobutene, Phenoxyethanol, Sorbitan Oleate, Caprylyl Glycol, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Triethanolamine, Beeswax, Tocopherol, Disodium EDTA, Stearic Acid, Myristyl Alcohol, Prunus Amygdalus Dulcis Oil, Prunus Armeniaca Kernel Oil, Persea Gratissima Oil

Caprylic/Capric Triglyceride

C12-15 Alkyl Benzoate

Cetearyl Alcohol

Glyceryl Stearate Se

Betaine

Butylene Glycol

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

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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.

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!

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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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  6. 06This 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.
  7. 07Because 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).
  8. 08In 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!).
  9. 09Besides hydration, shea butter also contains triterpenes that have anti-inflammatory potential. In particule, lupeol cinnamate has shown the highest anti-inflammatory activity in vivo.
  10. 10Shea butter also contains vitamins A and E which may contribute to antioxidant activity.
  11. 11While Shea Butter has an SPF rating of about 3-4, it is not a sunscreen replacement.
  12. 12This ingredient may not be fungal acne safe because its fatty acids fall within the C11-C24 range that the Malassezia yeast can metabolize.
  13. 13Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.
  14. 14Despite 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.
  15. 15It plays several roles in a formula:
  16. 16Typical 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.
  17. 17Multiple assessments have found it to be non-irritating and non-sensitizing to most people.
  18. 18However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.
  19. 19Cetearyl 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.
  20. 20Here'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.
Source · skinsort.com
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