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Skin science article

La Roche-Posay Toleriane Double Repair Face Moisturizer Versus rhode Peptide Glazing Fluid

La Roche-Posay Toleriane Double Repair Face Moisturizer Versus rhode Peptide Glazing Fluid This barrier-repair moisturizer is formulated around Squalane and Niacinamide to strengthen the skin barrier and hydrate skin. This barrier-repair serum is formulated ar

La Roche-Posay Toleriane Double Repair Face Moisturizer Versus rhode Peptide Glazing Fluid

This barrier-repair moisturizer is formulated around Squalane and Niacinamide to strengthen the skin barrier and hydrate skin.

This barrier-repair serum is formulated around Sclerocarya Birrea Seed Oil and Niacinamide to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Squalane

Dimethicone

Zea Mays Starch

Niacinamide

Ammonium Polyacryloyldimethyl Taurate

Myristyl Myristate

Stearic Acid

Ceramide NP

Potassium Cetyl Phosphate

Glyceryl Stearate Se

Sodium Hydroxide

Myristic Acid

Palmitic Acid

Capryloyl Glycine

Caprylyl Glycol

Xanthan Gum

Water, Glycerin, Squalane, Dimethicone, Zea Mays Starch, Niacinamide, Ammonium Polyacryloyldimethyl Taurate, Myristyl Myristate, Stearic Acid, Ceramide NP, Potassium Cetyl Phosphate, Glyceryl Stearate Se, Sodium Hydroxide, Myristic Acid, Palmitic Acid, Capryloyl Glycine, Caprylyl Glycol, Xanthan Gum

Butylene Glycol

Sclerocarya Birrea Seed Oil

Tetradecane

Capryloyl Glycerin/Sebacic Acid Copolymer

Diheptyl Succinate

Benzyl Alcohol

Glyceryl Oleate

Sucrose Palmitate

Hydroxyacetophenone

Carbomer

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Disodium Phosphate

Sodium Phosphate

Sodium Hyaluronate

Dilauryl Thiodipropionate

Acetyl Hexapeptide-8

Water, Butylene Glycol, Glycerin, Sclerocarya Birrea Seed Oil, Niacinamide, Tetradecane, Capryloyl Glycerin/Sebacic Acid Copolymer, Diheptyl Succinate, Benzyl Alcohol, Glyceryl Oleate, Sucrose Palmitate, Hydroxyacetophenone, Carbomer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Caprylyl Glycol, Sodium Hydroxide, Disodium Phosphate, Sodium Phosphate, Sodium Hyaluronate, Dilauryl Thiodipropionate, Acetyl Hexapeptide-8

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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

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.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

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.

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
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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. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.
  6. 06A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.
  7. 07Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  8. 08Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  9. 09Though 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.
  10. 10Carbomer 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.
  11. 11Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  12. 12It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  13. 13Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  14. 14A 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.
  15. 15Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  16. 16Topically, glycerin does several things at once:
  17. 17Your 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.
  18. 18Aquaporin-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.
  19. 19This 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.
  20. 20Just know very high concentrations (>40%) can feel tacky in low humidity.
Source · skinsort.com
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