Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

DRMTLGY Vitamin C E + F Versus Paula's Choice C15 Super Booster

DRMTLGY Vitamin C E + F Versus Paula's Choice C15 Super Booster This anti-aging serum is formulated around Ascorbic Acid and Tocopherol to soften the look of wrinkles and brighten dull-looking skin. This brightening serum is formulated around Ascorbic Acid and

DRMTLGY Vitamin C E + F Versus Paula's Choice C15 Super Booster

This anti-aging serum is formulated around Ascorbic Acid and Tocopherol to soften the look of wrinkles 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

Water

Ascorbic Acid

Ethoxydiglycol

PEG-40 Hydrogenated Castor Oil

PPG-26-Buteth-26

Glycerin

Tocopherol

Ferulic Acid

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Ceramide EOP

Ceramide NP

Palmitoyl Tripeptide-5

Ceramide AP

Phytosphingosine

Cholesterol

Sodium Lauroyl Lactylate

Butylene Glycol

Carbomer

Polysorbate 20

Xanthan Gum

Sodium Hyaluronate

Sodium Metabisulfite

Acetyl Octapeptide-3

Phenoxyethanol

Triethanolamine

Panthenol

Water, Ascorbic Acid, Ethoxydiglycol, PEG-40 Hydrogenated Castor Oil, PPG-26-Buteth-26, Glycerin, Tocopherol, Ferulic Acid, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Ceramide EOP, Ceramide NP, Palmitoyl Tripeptide-5, Ceramide AP, Phytosphingosine, Cholesterol, Sodium Lauroyl Lactylate, Butylene Glycol, Carbomer, Polysorbate 20, Xanthan Gum, Sodium Hyaluronate, Sodium Metabisulfite, Acetyl Octapeptide-3, Phenoxyethanol, Triethanolamine, Panthenol

Dipropylene Glycol

Propanediol

Sodium Hydroxide

Bisabolol

Sodium Phytate

Decylene Glycol

1,2-Hexanediol

Sphingomonas Ferment Extract

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

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.

Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.

In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling

This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.

It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.

The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it interacting gently with the lipids and water in your outermost layer of skin.

Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).

Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.

Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.

Ferulic Acid is a plant based antioxidant that can be naturally found in the cell walls of grains like rice, oats, and corn. It has antioxidant and antimicrobial properties, and has the ability to boost the performance of other antioxidants as well.

A well-known study found that adding Ferulic Acid to a solution of Vitamins C and E doubled the photoprotection of skin. This is why you'll often see it paired with Vitamin C or Vitamin E serums rather than sold on its own.

A 2025 review of 18 human studies found that using Ferulic Acid (0.5-1%) daily for one to three months showed improvements in:

As far as allergies go, Ferulic acid is generally well-tolerated but can cause an allergic reaction in very rare cases. It's also worth noting that Ferulic acid is often extracted from plant sources like rice bran or wheat bran, so be sure to path test if you have known grain allergies.

Outside of skincare, researchers are also looking into Ferulic Acid for its potential benefits in areas like diabetes, Alzheimer's, and heart health.

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.

PEG-40 Hydrogenated Castor Oil is an emulsifier derived from castor oil.

As an emulsifying agent, it helps other ingredients like fragrances and fat-soluble vitamins dissolve cohesively.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

We don't have a description for PPG-26-Buteth-26 yet.

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.

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 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. 03Cyclopentasiloxane (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.
  4. 04Since D5 is volatile, it does its thing and then evaporates off the skin quickly.
  5. 05The 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
  6. 06There'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.
  7. 07Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.
  8. 08The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.
  9. 09Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
  10. 10What it does:
  11. 11Dimethicone comes in different viscosities:
  12. 12Depending on the viscosity, dimethicone has different properties.
  13. 13Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
  14. 14This 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.
  15. 15Note: 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.
  16. 16Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  17. 17Topically, glycerin does several things at once:
  18. 18Your 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.
  19. 19Aquaporin-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.
  20. 20This 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.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side