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Paula's Choice C15 Super Booster Versus Stratia C+C Serum

Paula's Choice C15 Super Booster Versus Stratia C+C Serum This brightening serum is formulated around Ascorbic Acid and Ferulic Acid to brighten dull-looking skin and soften the look of wrinkles. This anti-aging serum is formulated around Ascorbic Acid and Asc

Paula's Choice C15 Super Booster Versus Stratia C+C Serum

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

This anti-aging serum is formulated around Ascorbic Acid and Ascorbyl Tetraisopalmitate to soften the look of wrinkles and fade the look of dark spots.

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

Cyclopentasiloxane

Isododecane

Ascorbyl Tetraisopalmitate

Hdi/Trimethylol Hexyllactone Crosspolymer

Polysilicone-11

Dimethicone

Ethylhexyl Hydroxystearate

Squalane

Ubiquinone

Silica

Cyclopentasiloxane, Isododecane, Ascorbic Acid, Ascorbyl Tetraisopalmitate, Hdi/Trimethylol Hexyllactone Crosspolymer, Polysilicone-11, Dimethicone, Ethylhexyl Hydroxystearate, Squalane, Tocopherol, Ubiquinone, Bisabolol, Silica

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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.

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.

Bisabolol is a gentle skin conditioner, antioxidant, and soothing ingredient.

It's primary claim to fame is soothing and research shows topically applied bisabolol can quiet the chemical messengers that cause your skin to become inflamed, helping to sooth any irritation.

A clinical study found that applying 0.5% bisabolol daily for 8 weeks produced an average 9% decrease in skin pigmentation. Researchers found it can also suppress the process that leads to excess melanin production in skin.

In vitro studies found that bisabolol combined with propylene glycol significantly increased skin permeability by increasing lipid fluidity in the stratum corneum.

You'll likely see use concentrations quite low, usually 0.1-0.2%.

Overall, this is a well-tolerated ingredient that works well in formulas designed for sensitive, reactive, or post-procedure skin.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on 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. 01Water
  2. 02Propylene Glycol
  3. 03Benzoyl Peroxide
  4. 04Bisabolol
  5. 05Allantoin
  6. 06Acrylates/C10-30 Alkyl Acrylate Crosspolymer
  7. 07Hydroxyethylcellulose
  8. 08Sodium Citrate
  9. 09Laureth-4
  10. 10Caprylyl Glycol
  11. 11Sodium Hydroxide
  12. 12Disodium EDTA
  13. 13Hexylene Glycol
  14. 14Phenoxyethanol
  15. 15Water, Propylene Glycol, Benzoyl Peroxide, Bisabolol, Allantoin, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Hydroxyethylcellulose, Sodium Citrate, Laureth-4, Caprylyl Glycol, Sodium Hydroxide, Disodium EDTA, Hexylene Glycol, Phenoxyethanol
  16. 16Salicylic Acid 1%
  17. 17Alcohol Denat.
  18. 18Butylene Glycol
  19. 19Polyacrylate Crosspolymer-6
  20. 20Camphor
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side