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Skin science article

Paula's Choice Probiotic Nutrient Moisturizer Versus Paula's Choice Omega+ Complex Moisturizer

Paula's Choice Probiotic Nutrient Moisturizer Versus Paula's Choice Omega+ Complex Moisturizer This barrier-repair moisturizer is formulated around Lactobacillus Ferment and Bifida Ferment Lysate to strengthen the skin barrier and hydrate skin. This barrier-re

Paula's Choice Probiotic Nutrient Moisturizer Versus Paula's Choice Omega+ Complex Moisturizer

This barrier-repair moisturizer is formulated around Lactobacillus Ferment and Bifida Ferment Lysate to strengthen the skin barrier and hydrate skin.

This barrier-repair moisturizer is formulated around Butyrospermum Parkii Butter and Linoleic Acid to strengthen the skin barrier and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Isoamyl Laurate

Glycerin

Butylene Glycol

Sodium Polyacrylate Starch

Cetyl Alcohol

Lauroyl Lysine

Lactobacillus/Rye Flour Ferment

Lactobacillus Ferment

Bifida Ferment Lysate

Glucomannan

Saccharomyces Lysate

Leuconostoc/Radish Root Ferment Filtrate

Glycine Soja Seed Extract

Camellia Sinensis Leaf Extract

Tetrahexyldecyl Ascorbate

Acetyl Hexapeptide-1

Palmitoyl Dipeptide-10

Ceramide Ng

Orbignya Oleifera Seed Oil

Palmitoyl Proline

Glycine

Serine

Threonine

Alanine

Valine

Arginine

Proline

Lysine Hcl

Rubus Idaeus Fruit Extract

Niacinamide

Adenosine

Lecithin

Phytic Acid

Yeast Extract

Faex

Tocopherol

Sodium PCA

Sodium Lactate

PCA

Magnesium Palmitoyl Glutamate

Sodium Palmitoyl Sarcosinate

Isopropyl Palmitate

Glutamic Acid

Betaine

Glyceryl Stearate

Hydroxyacetophenone

Sodium Acrylates Copolymer

Ceteth-20

Steareth-20

Polysorbate 20

PEG-75 Stearate

Caprylyl Glycol

Propylene Glycol

1,2-Hexanediol

Phenoxyethanol

Ethylhexylglycerin

Water, Isoamyl Laurate, Glycerin, Butylene Glycol, Sodium Polyacrylate Starch, Cetyl Alcohol, Lauroyl Lysine, Lactobacillus/Rye Flour Ferment, Lactobacillus Ferment, Bifida Ferment Lysate, Glucomannan, Saccharomyces Lysate, Leuconostoc/Radish Root Ferment Filtrate, Glycine Soja Seed Extract, Camellia Sinensis Leaf Extract, Tetrahexyldecyl Ascorbate, Acetyl Hexapeptide-1, Palmitoyl Dipeptide-10, Ceramide Ng, Orbignya Oleifera Seed Oil, Palmitoyl Proline, Glycine, Serine, Threonine, Alanine, Valine, Arginine, Proline, Lysine Hcl, Rubus Idaeus Fruit Extract, Niacinamide, Adenosine, Lecithin, Phytic Acid, Yeast Extract, Faex, Tocopherol, Sodium PCA, Sodium Lactate, PCA, Magnesium Palmitoyl Glutamate, Sodium Palmitoyl Sarcosinate, Isopropyl Palmitate, Glutamic Acid, Betaine, Glyceryl Stearate, Hydroxyacetophenone, Sodium Acrylates Copolymer, Ceteth-20, Steareth-20, Polysorbate 20, PEG-75 Stearate, Caprylyl Glycol, Propylene Glycol, 1,2-Hexanediol, Phenoxyethanol, Ethylhexylglycerin

Butyrospermum Parkii Butter

Ceteareth-6 Olivate

C13-15 Alkane

Polyglyceryl-4 Laurate

Decyl Oleate

Linum Usitatissimum Seed Oil

Salvia Hispanica Seed Oil

Olea Europaea Fruit Oil

Passiflora Edulis Seed Oil

Borago Officinalis Seed Oil

Hydrogenated Olive Oil

Psidium Guajava Fruit Extract

Olea Europaea Oil Unsaponifiables

Limnanthes Alba Seed Oil

Linoleic Acid

Linolenic Acid

Oleic Acid

Euterpe Oleracea Sterols

Ceramide AP

Ceramide EOP

Ceramide NP

Squalane

Cholesterol

Phytosphingosine

Anastatica Hierochuntica Extract

Sodium Hyaluronate

Boerhavia Diffusa Root Extract

Pullulan

Carbomer

Sclerotium Gum

Xanthan Gum

Sodium Lauroyl Lactylate

Water, Butyrospermum Parkii Butter, Ceteareth-6 Olivate, Butylene Glycol, C13-15 Alkane, Glycerin, Glyceryl Stearate, Polyglyceryl-4 Laurate, Decyl Oleate, Linum Usitatissimum Seed Oil, Salvia Hispanica Seed Oil, Olea Europaea Fruit Oil, Passiflora Edulis Seed Oil, Borago Officinalis Seed Oil, Hydrogenated Olive Oil, Psidium Guajava Fruit Extract, Olea Europaea Oil Unsaponifiables, Limnanthes Alba Seed Oil, Linoleic Acid, Linolenic Acid, Oleic Acid, Euterpe Oleracea Sterols, Ceramide AP, Ceramide EOP, Ceramide NP, Serine, Alanine, Glycine, Proline, Lysine Hcl, Threonine, Arginine, Squalane, Cholesterol, Phytosphingosine, Anastatica Hierochuntica Extract, Lecithin, Sodium Hyaluronate, Sodium Lactate, Boerhavia Diffusa Root Extract, Adenosine, Phytic Acid, Glutamic Acid, Betaine, Pullulan, PCA, Sodium PCA, Carbomer, Sodium Polyacrylate Starch, Sclerotium Gum, Xanthan Gum, Sodium Lauroyl Lactylate, Phenoxyethanol, Ethylhexylglycerin

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.

Adenosine is a purine nucleoside that your body already makes in every cell. In skincare, it acts mainly as a skin conditioning and anti-aging agent.

The way it works is fairly well mapped out:

Your skin has cells called fibroblasts that build collagen (the stuff that keeps skin firm and smooth). Adenosine basically flips a switch on these cells that tells them to get to work making more collagen and other proteins. These cells slow down on their own as skin ages, so Adenosine helps give them a little nudge to keep going.

The clinical backing is pretty solid too.

A blind, randomized, placebo-controlled trial of 126 women aged 45-65 tested a 0.1% cream twice daily and found real improvements in crow's feet and frown lines using a precise 3D skin-mapping technique; these changes showed up by week 3 and held at 2 months.

A later study using Adenosine-loaded dissolving microneedle patches reported gains in wrinkle depth, dermal density, elasticity, and hydration.

On concentrations, South Korea's Ministry of Food and Drug Safety has set 0.04% as the approved functional anti-wrinkle level. You'll typically see this ingredient used somewhere in the 0.04-0.1% range since it works at low doses.

This ingredient has been found safe for cosmetics with the data showing no irritation or sensitization.

Overall, this is a great ingredient for any anti-aging routine and has no photosensitizing effect, so it suits both AM and PM use.

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.

Betaine is a humectant. Like hyaluronic acid, it helps attract and retain moisture in the skin. It’s known for being gentle and for helping the skin maintain balanced hydration.

Betaine is mainly used to improve hydration and support calmer skin. It helps skin cells regulate water balance because it functions as an osmolyte.

Some studies suggest betaine may support making skin tone more even.

Fun fact: Betaine naturally exists in the skin and the body. In cosmetic products, it can be either plant-derived (most commonly from sugar beets) or synthetically produced for consistency and stability.

Betaine is also known as trimethylglycine.

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.

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.

Glutamic Acid is an amino acid that is found in all living organisms. Our bodies use this to help nerve cells in the brain communicate with other cells.

In cosmetics, glutamic acid is a famous humectant. It draws water from the air to your skin, keeping your skin hydrated (like hyaluronic acid).

An in-vitro study from 2024 found glutamic acid to play a role in inhibiting inflammation and thus a potential skin-soothing ingredient.

Other studies show it to be have potential wound healing, skin barrier repair, and hair growth properties.

Glutamic acid has poor solubility in water and other solvents.

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.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

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.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

Lysine HCl is an alpha amino acid salt.

Our skin uses amino acids as a precursor for building protein, and therefore keratins, collagen and elastin.

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.

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.

Phytic Acid is a gentle AHA and antioxidant. AHAs are chemical exfoliants that help remove dead skin cells. Phytic Acid has a slight and mild exfoliating effect.

The chemical makeup makes it classified as an AHA, much like lactic acid.

In some cases, it is a chelating agent. Chelating agents help prevent metals from binding to water, helping to stabilize the ingredients in a product.

An interesting fact about phytic acid is that it is considered an antinutrient. People do not have the enzyme needed to properly breakdown and digest phytic acid. When ingested, phytic acid binds to minerals and prevents them from being absorbed.

Read more about some other popular AHA's here:

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 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%.

We don't have a description for Sodium Polyacrylate Starch yet.

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.

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. 03Phytosphingosine is a phospholipid naturally found in our skin as a building block for ceramides.. It helps moisturize, soothe, and protect skin.
  4. 04Phytosphingosine contributes to your skin's natural moisturizing factor (NMF). The NMF is responsible for hydration, a strong barrier, and plasticity. Our NMF decreases with age. Increasing NMF leads to more healthy and hydrated skin.
  5. 05Studies show products formulated with NMF ingredients help strengthen our skin's barrier. Having a healthy skin barrier reduces irritation and increases hydration. Our skin barrier is responsible for having plump and firm skin. It also helps protect…
  6. 06Fun fact: Phytosphingosine is abundant in plants and fungi.
  7. 07More ingredients that help boost collagen in skin:
  8. 08Salicylic 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, …
  9. 09Unlike 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.
  10. 10Salicylic 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.
  11. 11Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.
  12. 12It 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.
  13. 13While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.
  14. 14If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.
  15. 15Tetrasodium EDTA is the salt formed from neutralizing ethylenediamine tetraacetic acid with sodium hydroxide. It is a chelating agent and used to prevent metal ions from binding to other ingredients. This helps keep the product and ingredients stable.
  16. 16Tetrasodium EDTA comes as a white solid and is soluble in water.
  17. 17Water. 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.
  18. 18So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.
  19. 19You'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!
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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