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Prequel Half & Half Peptides & Ceramides Fluid Moisturizer Versus Geek & Gorgeous Power Peptides Serum

Prequel Half & Half Peptides & Ceramides Fluid Moisturizer Versus Geek & Gorgeous Power Peptides Serum This barrier-repair moisturizer is formulated around Ceramide NP and Hexapeptide-11 to strengthen the skin barrier and soften the look of wrinkles. This anti

Prequel Half & Half Peptides & Ceramides Fluid Moisturizer Versus Geek & Gorgeous Power Peptides Serum

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

This anti-aging serum is formulated around Palmitoyl Tripeptide-1 and Palmitoyl Tetrapeptide-7 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

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

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

Pentylene Glycol

Polyglyceryl-6 Stearate

Caprylic/Capric Triglyceride

Panthenol

Dicaprylyl Carbonate

Dicaprylyl Ether

Potassium Cetyl Phosphate

Polyglyceryl-6 Behenate

Tetrapeptide-21

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-38

Copper Palmitoyl Heptapeptide-14

Heptapeptide-15 Palmitate

Saccharide Isomerate

Allantoin

Cetearyl Alcohol

Glyceryl Stearate Se

Tapioca Starch

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Hydroxypropyl Cyclodextrin

Lactic Acid/Glycolic Acid Copolymer

Polyvinyl Alcohol

Sodium Citrate

Water, Glycerin, Butylene Glycol, Pentylene Glycol, Polyglyceryl-6 Stearate, Caprylic/Capric Triglyceride, Panthenol, Dicaprylyl Carbonate, Dicaprylyl Ether, Potassium Cetyl Phosphate, Polyglyceryl-6 Behenate, Tetrapeptide-21, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-38, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Saccharide Isomerate, Allantoin, Cetearyl Alcohol, Glyceryl Stearate Se, Tapioca Starch, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Carbomer, Polysorbate 20, Hydroxypropyl Cyclodextrin, Lactic Acid/Glycolic Acid Copolymer, Polyvinyl Alcohol, Citric Acid, Sodium Citrate, Sodium Hydroxide, Phenoxyethanol, Ethylhexylglycerin

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Carbomer 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.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

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.

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.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

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.

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.

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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. 03Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.
  4. 04It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.
  5. 05Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.
  6. 06A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.
  7. 07Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.
  8. 08One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.
  9. 09Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.
  10. 10Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  11. 11Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.
  12. 12However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  13. 13Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.
  14. 14In skincare formulas, citric acid can:
  15. 15While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  16. 16Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.
  17. 17Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.
  18. 18However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's…
  19. 19Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  20. 20Topically, glycerin does several things at once:
Source · skinsort.com
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Comparison edit

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