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Summer Fridays Dream Oasis Deep Hydration Serum Versus The INKEY List Ceramide Night Treatment

Summer Fridays Dream Oasis Deep Hydration Serum Versus The INKEY List Ceramide Night Treatment This hydrating serum is formulated around Squalane and Aloe Barbadensis Leaf Juice to hydrate skin and strengthen the skin barrier. This barrier-repair night moistur

Summer Fridays Dream Oasis Deep Hydration Serum Versus The INKEY List Ceramide Night Treatment

This hydrating serum is formulated around Squalane and Aloe Barbadensis Leaf Juice to hydrate skin and strengthen the skin barrier.

This barrier-repair night moisturizer is formulated around Sodium Hyaluronate and Ceramide NP to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Squalane

Glycerin

Cetyl Ethylhexanoate

Aloe Barbadensis Leaf Juice

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Polyester-5

Sodium Hyaluronate

Avena Sativa Kernel Flour

Sodium PCA

Panthenol

Ceramide NP

Arnica Montana Flower Extract

Laminaria Digitata Extract

Centella Asiatica Extract

Palmitoyl Tripeptide-38

Niacinamide

Acetyl Glucosamine

Arginine

Aspartic Acid

PCA

Glycine

Alanine

Serine

Valine

Proline

Threonine

Isoleucine

Phenylalanine

Histidine

Sodium Lactate

Caprylhydroxamic Acid

Glyceryl Stearate

Disodium EDTA

Sodium Hydroxide

Polyglyceryl-3 Methylglucose Distearate

Sodium Benzoate

Citric Acid

Hydroxypropyl Cyclodextrin

Xanthan Gum

Potassium Sorbate

1,2-Hexanediol

Propylene Glycol

Water, Propanediol, Squalane, Glycerin, Cetyl Ethylhexanoate, Aloe Barbadensis Leaf Juice, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Polyester-5, Sodium Hyaluronate, Avena Sativa Kernel Flour, Sodium PCA, Panthenol, Ceramide NP, Arnica Montana Flower Extract, Laminaria Digitata Extract, Centella Asiatica Extract, Palmitoyl Tripeptide-38, Niacinamide, Acetyl Glucosamine, Arginine, Aspartic Acid, PCA, Glycine, Alanine, Serine, Valine, Proline, Threonine, Isoleucine, Phenylalanine, Histidine, Sodium Lactate, Caprylhydroxamic Acid, Glyceryl Stearate, Disodium EDTA, Sodium Hydroxide, Polyglyceryl-3 Methylglucose Distearate, Sodium Benzoate, Citric Acid, Hydroxypropyl Cyclodextrin, Xanthan Gum, Potassium Sorbate, 1,2-Hexanediol, Propylene Glycol

Butylene Glycol

Simmondsia Chinensis Seed Oil

Carbomer

Phenoxyethanol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Benzyl Alcohol

Sodium Lauroyl Lactylate

Sodium Stearoyl Glutamate

Ethylhexylglycerin

Sodium Gluconate

Polysorbate 60

Dehydroacetic Acid

Sorbitan Isostearate

Ceramide AP

Phytosphingosine

Cholesterol

Ceramide EOP

Water, Butylene Glycol, Glycerin, Sodium Hyaluronate, Simmondsia Chinensis Seed Oil, Carbomer, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Benzyl Alcohol, Squalane, Sodium Lauroyl Lactylate, Sodium PCA, Sodium Hydroxide, Sodium Stearoyl Glutamate, Sodium Lactate, Arginine, Aspartic Acid, Ethylhexylglycerin, Sodium Gluconate, PCA, Polysorbate 60, Dehydroacetic Acid, Ceramide NP, Glycine, Alanine, Sorbitan Isostearate, Ceramide AP, Phytosphingosine, Serine, Cholesterol, Valine, Xanthan Gum, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Ceramide EOP

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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.

Alanine is an amino acid and is already found in the human body. Our skin uses alanine to build collagen, elastin, and keratin.

Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.

It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Aspartic Acid is an amino acid that our bodies produce naturally. It is an antioxidant.

Our body uses Aspartic Acid to help build collagen and elastin. It also plays a role in hydrating skin.

Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.

Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.

This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.

A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.

Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.

Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.

Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.

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.

Glycine is the smallest amino acid and a key building block of collagen. It's part if your skin's Natural Moisturizing Factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

A study from 2022 found that an amino acid complex featuring taurine, arginine, and glycine significantly reduced skin irritation, improved redness, and accelerated the skin repair process.

Histidine is a semi-essential amino acid used by our bodies to create protein. It has humectant and skin conditioning properties.

Our bodies use histidine to create filaggrin - filaggrin is a structural protein that the skin uses in maintaining skin barrier.

One study found histidine and carnosine to be a dynamic duo for your skin:

Oral histidine has also been found to help with filaggrin-deficit skin disorders such as atopic dermatitis.

Why is it considered a semi-essential amino acid? This is because adults are able to create it but children must get it from their diet.

Isoleucine is an amino acid that helps reinforce our skin barrier. This amino acid plays a role in creating protein for the body.

Fun fact: Isoleucine is found in meat, fish, dairy, legumes, and nuts.

PCA is an amino acid derivative and one of the star players in your skin's own Natural Moisturizing Factor (NMF).

The NMF is the built-in cocktail of small molecules that keeps your outer layer of skin hydrated and your body makes it naturally.

This is why it works so well topically; PCA is a humectant that holds water in the stratum corneum and studies link higher skin PCA levels to better hydration + lower water loss. Interestingly, people show more PCA in summer and in normal vs dry skin.

Most of the benefits of this ingredient are related to hydration, softness, and barrier support.

A long-running review found that formulas with at least 2% PCA or its salts improved dry skin over both the short and long term. And the zinc salt is also used for its mild antimicrobial and astringent properties.

The salt forms are more common in cosmetics (like sodium PCA).

This ingredient is compatible with basically everything and pairs well with other humectants like glycerin or hyaluronic acid.

Usage-wise, it's typically used at low percentages (~0.2-2%).

The Cosmetic Ingredient Review Expert Panel has concluded PCA and its salts are safe as used and is non-irritating on skin even at high concentrations.

Phenylalanine is an amino acid. It is a skin soothing and hydrating ingredient. Amino acids play a crucial role in wound healing and skin hydration.

This ingredient is also used to help even out skin tone due to its ability to disrupt the melanin production process.

Two structures of phenylalanine exist: L-phenylalanine and D-phenylalanine. L-phenylalanine is essential, this means our bodies cannot produce it naturally and we must get it from foods. Our bodies convert D-phenylalanine to neurotransmitters, and D-phenylalanine is found in our bodies naturally.

Some foods that contain L-phenylalanine include eggs, soybeans, beef, milk.

Proline is a non-essential amino acid, meaning your body can make it on its own. In skincare, it is a skin conditioning ingredient that keeps skin soft and hydrated.

It makes up about 23% of the collagen molecule (collagen is the protein responsible for keeping your skin firm) and is involved in your skin's natural hyaluronic acid production. When applied topically, proline can penetrate the skin fairly well due to its small molecular size.

Reviews of this ingredient have found it to be neither a dermal irritant nor a sensitizer.

Fun fact: Proline can be found in protein-rich foods like meat, fish, eggs, and dairy.

Serine is a non-essential amino acid (your body makes it on its own!). It is a major player in your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Serine is one of your NMF's most abundant components that works as a skin-identical humectant. Its hydroxyl group grabs onto water molecules to boost hydration without any heaviness or occlusion.

Research on a hydrogel with serine confirmed this serine got delivered to your stratum corneum and demonstrated enhanced skin moisturization.

Interestingly serine also helps your skin produce filaggrin, a protein that keeps your skin barrier strong and used to create collagen.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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.

Sodium Lactate is the sodium salt of lactic acid, an AHA. It is a humectant and sometimes used to adjust the pH of a product.

This ingredient is part of our skin's NMF, or natural moisturizing factor. Our NMF is essential for the hydration of our top skin layers and plasticity of skin. NMF also influences our skin's natural acid mantle and pH, which protects our skin from harmful bacteria.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Sodium PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

Threonine is an amino-acid. It helps hydrate the skin and has antioxidant benefits.

Our skin uses threonine for creating collagen and elastin. Humans are not able to create threonine and must get it through eating foods such as fish, lentils, poultry, sesame seeds, and more.

Valine is one of the essential amino acids (meaning your body can't make it on its own and has to get it from food).

In skincare, it's usually synthetically-made or pulled from plant proteins like soy.

It's one of the small building blocks that make up your skin's natural moisturizing factor (NMF), or the built-in system that helps skin hold onto water. So its main job in a formula is to give the skin gentle hydration and help it feel more comfortable.

Typical amounts are very tiny: roughly 0.00004%-0.5% in leave on products and up to 1% in rinse-off ones.

The Cosmetic Ingredient Review panel has looked at this ingredient and found no evidence of it being a skin irritant or allergen at cosmetic levels.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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. 01Salicylic Acid 2%
  2. 02Water
  3. 03Betaine
  4. 04Butylene Glycol
  5. 05Chamomilla Recutita Flower Extract
  6. 06Glycerin
  7. 07Hydroxyacetophenone
  8. 08Pentylene Glycol
  9. 09Phenoxyethanol
  10. 10Potassium Sorbate
  11. 11Propanediol
  12. 12Sodium Benzoate
  13. 13Sodium Citrate
  14. 14Sorbic Acid
  15. 15Spirulina Platensis Extract
  16. 16Salicylic Acid 2%, Water, Betaine, Butylene Glycol, Chamomilla Recutita Flower Extract, Glycerin, Hydroxyacetophenone, Pentylene Glycol, Phenoxyethanol, Potassium Sorbate, Propanediol, Sodium Benzoate, Sodium Citrate, Sorbic Acid, Spirulina Platensi…
  17. 17Salicylic Acid
  18. 18Sodium Hyaluronate
  19. 19Zinc PCA
  20. 20Hydroxyethylcellulose
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List PHA Toner

The Inkey List PHA Toner The Inkey List PHA Toner ingredients explained: Water (Aqua/Eau), Propanediol, Gluconolactone, Niacinamide, Pentylene Glycol, Glycerin, Aloe Barbadensis Leaf Juice,…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side