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Prequel Multi-Acid Milk Peel AHA Exfoliating Solution Versus Prequel Half & Half Peptides & Ceramides Fluid Moisturizer

Prequel Multi-Acid Milk Peel AHA Exfoliating Solution Versus Prequel Half & Half Peptides & Ceramides Fluid Moisturizer This smoothing exfoliator is formulated around Glycolic Acid and Mandelic Acid to refine skin texture and brighten dull-looking skin. This b

Prequel Multi-Acid Milk Peel AHA Exfoliating Solution Versus Prequel Half & Half Peptides & Ceramides Fluid Moisturizer

This smoothing exfoliator is formulated around Glycolic Acid and Mandelic Acid to refine skin texture and brighten dull-looking skin.

This barrier-repair moisturizer is formulated around Ceramide NP and Hexapeptide-11 to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycolic Acid

Sodium Hydroxide

Glycerin

Propanediol

Ethylhexyl Olivate

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

C13-14 Isoparaffin

C11-12 Isoparaffin

Phytic Acid

Malic Acid

Mandelic Acid

Lactic Acid

Lipase

Protease

Squalane

Polyglyceryl-10 Stearate

C15-23 Alkane

Hydroxyacetophenone

Phenoxyethanol

Tricaprylin

Glyceryl Oleate

Ethylhexyl Polyhydroxystearate

Tetradecane

C13-14 Alkane

Decyl Glucoside

Maltodextrin

Xanthan Gum

Lecithin

Sclerotium Gum

Polyglyceryl-4 Oleate

Carrageenan

Silica

Water, Glycolic Acid, Sodium Hydroxide, Glycerin, Propanediol, Ethylhexyl Olivate, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, C13-14 Isoparaffin, C11-12 Isoparaffin, Phytic Acid, Malic Acid, Mandelic Acid, Lactic Acid, Lipase, Protease, Squalane, Polyglyceryl-10 Stearate, C15-23 Alkane, Hydroxyacetophenone, Phenoxyethanol, Tricaprylin, Glyceryl Oleate, Ethylhexyl Polyhydroxystearate, Tetradecane, C13-14 Alkane, Decyl Glucoside, Maltodextrin, Xanthan Gum, Lecithin, Sclerotium Gum, Polyglyceryl-4 Oleate, Carrageenan, Silica

Isopropyl Myristate

Hydrolyzed Rice Protein

Ceramide NP

Ceramide As

Ceramide Ns

Ceramide EOP

Ceramide AP

Hexapeptide-11

Matrixyl 3000

Triolein

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Undecane

Glyceryl Dioleate

Caprylyl Glycol

Tridecane

Betaine

Sodium Stearoyl Glutamate

Citric Acid

Sodium Phytate

Sodium PCA

Sodium Lactate

PCA

Sodium Benzoate

Serine

Alanine

Palmitic Acid

Glycine

Hydrogenated Lecithin

Ethylhexyl Palmitate

Butylene Glycol

Ethylhexylglycerin

Glutamic Acid

Lysine Hcl

Threonine

Arginine

Proline

Tocopherol

Carbomer

Polysorbate 20

Water, Glycerin, Propanediol, Isopropyl Myristate, Ethylhexyl Olivate, Squalane, Hydrolyzed Rice Protein, Ceramide NP, Ceramide As, Ceramide Ns, Ceramide EOP, Ceramide AP, Hexapeptide-11, Matrixyl 3000, Polyglyceryl-10 Stearate, Triolein, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Glyceryl Oleate, Undecane, Hydroxyacetophenone, Glyceryl Dioleate, Caprylyl Glycol, Xanthan Gum, Tridecane, Betaine, Sodium Stearoyl Glutamate, Citric Acid, Sodium Phytate, Sodium PCA, Sodium Hydroxide, Sodium Lactate, PCA, Sodium Benzoate, Serine, Alanine, Palmitic Acid, Glycine, Hydrogenated Lecithin, Ethylhexyl Palmitate, Butylene Glycol, Phenoxyethanol, Ethylhexylglycerin, Glutamic Acid, Lysine Hcl, Threonine, Arginine, Proline, Tocopherol, Carbomer, Polysorbate 20

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.

Ethylhexyl Olivate isn't fungal acne safe.

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.

Glyceryl Oleate is the monoester of glycerin and oleic acid. It is a skin-conditioning emollient that also helps form emulsions.

What makes glyceryl oleate special is its "re-fatting" effect.

When you wash your hair and skin with a surfactant-based cleanser, the surfactants grab onto everything. This includes your skin's natural lipids, or the fats that live in your skin barrier and sebum. Once you rinse these surfactants away, it leaves your skin feeling tight, dry, and clean (in a not-good way).

Re-fatting is essentially putting some of these lipids back. Glyceryl oleate deposits a thin layer of emollient lipids back on the skin or hair surface reduce some of the barrier damage.

Also, glyceryl oleate isn't a foreign molecule to your skin. It's chemically identical to something your skin already produces and manages naturally. This is why it tends to be well-tolerated with low risk of irritation.

Typical use levels range from 0.5-5%.

Glyceryl Oleate has a function of "perfuming" in the CosIng database. This just means that the ingredient has some scent character that can contribute to the product's overall smell.

The scent of this ingredient is described as "waxy".

As an ester of oleic acid, this ingredient may not be fungal acne safe. This is because oleic acid falls into the carbon-chain length that Malassezia can use as a substrate.

Hydroxyacetophenone is a small phenolic molecule that earns its place in a formulas as an antioxidant and preservative booster.

As a phenol, it is able to neutralize free radicals to protect both the product and the skin from oxidative stress.

Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol.

This ingredient naturally occurs as piceol in Norwegian spruce needles (~0.4-1.1% dry weight and in cloudberries). Though the cosmetic-grade material is synthesized for purity and consistency.

You'll usually see it used at low levels and suppliers recommend up to 1% added to a water phase.

Safety testing was done at concentrations like 0.05% in SPF products and 0.5% in a Human Repeated Insult Patch Test. The safety evidence is assuring; this ingredient is safe for cosmetics in current use and also holds safety status as a food flavoring as well.

An honest caveat: the "soothing" and "anti-inflammatory" claims come mostly from supplier marketing rather than published clinical trials. The Cosmetic Ingredient Review's own literature search found no useful efficacy studies on this ingredient.

So the antioxidant and preservative-boosting roles are the well supported ones while the calming benefit is plausible but thinly evidenced.

Overall, this is a well-tolerated, low-irritation multitasker that quietly helps a formula stay fresh and stable.

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.

Polyglyceryl-10 Stearate is a skin conditioner that is basically a fatty acid (stearic acid) hooked up to a chain of glycerin units.

It is a skin conditioning agent that helps skin feel soft, smooth, and hydrated.

Beyond that, it also helps emulsify and cleanse: it helps oil and water phases stay blended in moisturizers, serums, and cleansers.

This ingredient has been found to be safe in cosmetics at present concentrations and practices of use.

Research on Malassezia shows the yeast can metabolize stearic acid as a growth substrate; this ingredient is not fungal acne safe.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food 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 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. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  7. 07Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  8. 08It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  9. 09Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  10. 10A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  11. 11Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.
  12. 12Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.
  13. 13This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.
  14. 14A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.
  15. 15Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.
  16. 16Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.
  17. 17Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.
  18. 18Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  19. 19Topically, glycerin does several things at once:
  20. 20Your 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.
Source · skinsort.com
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Comparison edit

Read side by side