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Cetaphil Bright Healthy Radiance Perfecting Serum Versus Olay Vitamin C + Peptide 24 Brightening Serum

Cetaphil Bright Healthy Radiance Perfecting Serum Versus Olay Vitamin C + Peptide 24 Brightening Serum This brightening serum is formulated around Niacinamide and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots. This brigh

Cetaphil Bright Healthy Radiance Perfecting Serum Versus Olay Vitamin C + Peptide 24 Brightening Serum

This brightening serum is formulated around Niacinamide and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and fade the look of dark spots.

This brightening serum is formulated around Niacinamide and Lactic Acid to brighten dull-looking skin and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Niacinamide

Dimethicone

3-O-Ethyl Ascorbic Acid

Acetyl Glycyl Beta-Alanine

Sodium Polyacryloyldimethyl Taurate

Phenoxyethanol

Undecane

Xanthan Gum

Tridecane

Xylitylglucoside

Anhydroxylitol

Calcium Aluminum Borosilicate

Xylitol

Hydrolyzed Hyaluronic Acid

Sodium Hydroxide

Pancratium Maritimum Extract

CI 77891

Tin Oxide

Tocopherol

Helianthus Annuus Seed Oil

Water, Glycerin, Niacinamide, Dimethicone, 3-O-Ethyl Ascorbic Acid, Acetyl Glycyl Beta-Alanine, Sodium Polyacryloyldimethyl Taurate, Phenoxyethanol, Undecane, Xanthan Gum, Tridecane, Xylitylglucoside, Anhydroxylitol, Calcium Aluminum Borosilicate, Xylitol, Hydrolyzed Hyaluronic Acid, Sodium Hydroxide, Pancratium Maritimum Extract, CI 77891, Tin Oxide, Tocopherol, Helianthus Annuus Seed Oil

Lactic Acid

Polyacrylate Crosspolymer-6

Palmitoyl Pentapeptide-4

Panthenol

Trehalose

PEG-11 Methyl Ether Dimethicone

Sodium Lactate

Sodium Benzoate

Parfum

Hydroxylauric Acid

Ascorbic Acid

Avena Sativa Peptide

Water, Glycerin, Dimethicone, Niacinamide, Lactic Acid, Polyacrylate Crosspolymer-6, 3-O-Ethyl Ascorbic Acid, Palmitoyl Pentapeptide-4, Panthenol, Trehalose, PEG-11 Methyl Ether Dimethicone, Sodium Lactate, Sodium Benzoate, Parfum, Hydroxylauric Acid, Ascorbic Acid, Avena Sativa Peptide

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.

3-O-Ethyl Ascorbic Acid is one of the most popular "stable" vitamin C derivatives in skincare.

Plain ascorbic acid is fantastic but notoriously fragile; it browns, oxidizes, and loses potency fast. So attaching an ethyl group to the third carbon of the molecule gives it some cool perks:

In a formula, it does the 3 classic vitamin C jobs: it acts as an antioxidant, helps brighten skin tone by inhibiting tyrosinase, and supports collagen.

The evidence is reasonably solid for a cosmetic ingredient; Liao and colleagues (2018) showed it's significantly more stable than ascorbic acid while still being effective.

A 2021 study by Zerbinati and colleagues tested a serum with 30% 3-O-ethyl-l-ascorbic acid and 1% lactic acid significantly increased collagen production, reduced UVB-induced DNA damage, and decreased melanin on a reconstructed pigmented skin model.

Typical real world usage sits around 0.5-5% (and 1-2% is common for daily serums).

Amounts up to 30% have been shown to be non-irritating on human skin samples, but two isolated cases reported allergic contact dermatitis so a patch test is sensible if you have reactive skin.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

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 Side-by-side

  1. 01Water
  2. 02Glycerin
  3. 03Dimethicone
  4. 04Niacinamide
  5. 05Lactic Acid
  6. 06Polyacrylate Crosspolymer-6
  7. 073-O-Ethyl Ascorbic Acid
  8. 08Palmitoyl Pentapeptide-4
  9. 09Panthenol
  10. 10Trehalose
  11. 11PEG-11 Methyl Ether Dimethicone
  12. 12Sodium Lactate
  13. 13Sodium Benzoate
  14. 14Parfum
  15. 15Hydroxylauric Acid
  16. 16Ascorbic Acid
  17. 17Avena Sativa Peptide
  18. 18Water, Glycerin, Dimethicone, Niacinamide, Lactic Acid, Polyacrylate Crosspolymer-6, 3-O-Ethyl Ascorbic Acid, Palmitoyl Pentapeptide-4, Panthenol, Trehalose, PEG-11 Methyl Ether Dimethicone, Sodium Lactate, Sodium Benzoate, Parfum, Hydroxylauric Aci…
  19. 19Pentylene Glycol
  20. 20Sodium Hydroxide
Source · skinsort.com
02

Product index

Related product references

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Comparison edit

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