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Neutrogena Rapid Tone Repair 20% Vitamin C Serum Capsules Versus Paula's Choice C15 Super Booster

Neutrogena Rapid Tone Repair 20% Vitamin C Serum Capsules Versus Paula's Choice C15 Super Booster This brightening serum is formulated around Ascorbic Acid to fade the look of dark spots and brighten dull-looking skin. This brightening serum is formulated arou

By Peptide Skincare & Beauty Editorial TeamPublished

Neutrogena Rapid Tone Repair 20% Vitamin C Serum Capsules Versus Paula's Choice C15 Super Booster

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

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Dimethicone

Ascorbic Acid

Trisiloxane

Dimethiconol

Silica Dimethyl Silylate

Dimethicone/Vinyltrimethylsiloxysilicate Crosspolymer

Tocopheryl Acetate

Caprylic/Capric Triglyceride

Diethylhexyl Syringylidenemalonate

Rubus Idaeus Leaf Extract

Dimethicone, Ascorbic Acid, Trisiloxane, Dimethiconol, Silica Dimethyl Silylate, Dimethicone/Vinyltrimethylsiloxysilicate Crosspolymer, Tocopheryl Acetate, Caprylic/Capric Triglyceride, Diethylhexyl Syringylidenemalonate, Rubus Idaeus Leaf Extract

Water

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

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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.

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 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. 03Benzalkonium Chloride (aka BAC) is a preservative that has been around since the 1930's. It is also a surfactant that gives it mild cleansing and antistatic properties.
  4. 04BAC works because it carries a positive electrical charge that attract the negative charge of microbe cells (like a magnet). Once BAC sticks to a microbe, it breaks the microbe cell's outer wall and scrambles its proteins to kill it.
  5. 05The maximum usage percentage for this ingredient is 0.1% in both the EU and Chinese cosmetic regulations.
  6. 06The CIR Expert Panel has concluded it to be a safe antimicrobial agent in concentrations up to 0.1% and it is permitted up to 3% in rinse off hair products.
  7. 07BAC can be irritating at higher concentrations but a true allergy to it is pretty rare. Be sure to patch test if you have a damaged skin barrier or just sensitive skin.
  8. 08Because it's a cation, it is incompatible with anionic surfactants like SLS (they neutralize each other).
  9. 09Benzyl Alcohol is an aromatic alcohol with several roles: it's a preservative, solvent, and mild fragrance component with a floral scent.
  10. 10This ingredient has been deemed safe for use in cosmetic formulations at concentrations up to 5%, and up to 10% in hair dyes. You'll typically see 0.5-2% in most rinse-off or leave-on products.
  11. 11As a preservative, it works by disrupting the membrane of microbial proteins. This helps keep bacteria and fungi from growing in your products.
  12. 12The sensitization picture is actually quite assuring as well:of nearly 71,000 patients patch tested with benzyl alcohol, only 0.21% showed a positive reaction with most of them being weakly positive.
  13. 13This led researchers to conclude that benzyl alcohol cannot be regarded as a significant contact allergen.
  14. 14It is worth noting this ingredient is classified as one of the EU's regulated fragrance allergens and restricted to 1% in finished products.
  15. 15Labels must also declare it in concentrations above 0.001% in leave-on products and 0.01% in rinse-off products.
  16. 16At concentrations around 5%, localized redness and itching can appear as a direct irritant response and not as a true allergic reaction.
  17. 17Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.
  18. 18Since D5 is volatile, it does its thing and then evaporates off the skin quickly.
  19. 19The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics
  20. 20There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.
Source · skinsort.com ⟶
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Product index

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03

Comparison edit

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