Paula's Choice C15 Super Booster Versus Olay Vitamin C + Peptide 24

Paula's Choice C15 Super Booster Versus Olay Vitamin C + Peptide 24

This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles.

This brightening moisturizer is formulated around Niacinamide and 3-O-Ethyl Ascorbic Acid to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Ascorbic Acid

Dipropylene Glycol

Propanediol

Glycerin

Ethoxydiglycol

Sodium Hydroxide

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Bisabolol

Ferulic Acid

Sodium Phytate

Decylene Glycol

Tocopherol

1,2-Hexanediol

Sphingomonas Ferment Extract

Phenoxyethanol

Water, Ascorbic Acid, Dipropylene Glycol, Propanediol, Glycerin, Ethoxydiglycol, Sodium Hydroxide, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Bisabolol, Ferulic Acid, Sodium Phytate, Decylene Glycol, Tocopherol, 1,2-Hexanediol, Sphingomonas Ferment Extract, Phenoxyethanol

Isohexadecane

Niacinamide

Dimethicone

Lactic Acid

Isopropyl Isostearate

Sodium Polyacryloyldimethyl Taurate

Stearyl Alcohol

3-O-Ethyl Ascorbic Acid

Palmitoyl Pentapeptide-4

Panthenol

Sodium Lactate

Trehalose

Cetearyl Glucoside

Cetearyl Alcohol

Behenyl Alcohol

Cetyl Alcohol

Stearic Acid

Palmitic Acid

Dimethiconol

PEG-100 Stearate

Sodium Benzoate

Parfum

Avena Sativa Peptide

Water, Glycerin, Isohexadecane, Niacinamide, Dimethicone, Lactic Acid, Isopropyl Isostearate, Sodium Polyacryloyldimethyl Taurate, Stearyl Alcohol, 3-O-Ethyl Ascorbic Acid, Palmitoyl Pentapeptide-4, Panthenol, Sodium Lactate, Trehalose, Cetearyl Glucoside, Cetearyl Alcohol, Behenyl Alcohol, Cetyl Alcohol, Stearic Acid, Palmitic Acid, Dimethiconol, PEG-100 Stearate, Sodium Benzoate, Parfum, 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.

Ascorbic Acid is is pure Vitamin C and is the biologically active form used directly by skin.

Not only is vitamin C great for your overall health and immune system, but it also has plenty of benefits for your skin. It is best supported by academic literature for:

Topical vitamin C has been shown to help neutralize oxidative stress from UV and pollution, helping to improve photoaging and hyperpigmentation when used consistently.

One clinical study found that using 5% topical vitamin C for six months improved signs of photodamaged skin, both on the surface and in the deeper structural layers of the skin.

While vitamin C doesn’t replace sunscreen, studies show it can boost photoprotection when combined with Vitamin E and ferulic acid. These two ingredients help improve stability and protective effects.

The big downside of this ingredient is formulation difficulty. Vitamin C is prone to oxidation and doesn't penetrate the skin unless formulated correctly. Research found that vitamin C absorbs into the skin best at a low pH (< 3.5) with about 20% being the upper limit for effective absorption.

Skin levels can saturate after repeated application; this means your skin won’t keep absorbing more once it’s full of vitamin C. This is why more isn’t always better with vitamin C and why very high concentrations don’t necessarily give extra benefits.

Ascorbic acid generally works well with many skincare ingredients but can be irritating when combined with other active ingredients. Strong oxidizing acne treatments like benzoyl peroxide can reduce the effectiveness of vitamin C if they are used at the same time; they are often recommended for use at different times of day.

Read more about other types of Vitamin C:

Foods rich with vitamin C include oranges, strawberries, broccoli, bell peppers, and more. When consuming Vitamin C, your skin receives a portion of the nutrients.

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.

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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