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Medik8 Advanced Pro-Collagen+ Peptide Cream Versus Paula's Choice Pro-Collagen Peptide Plumping Moisturizer

Medik8 Advanced Pro-Collagen+ Peptide Cream Versus Paula's Choice Pro-Collagen Peptide Plumping Moisturizer This anti-aging moisturizer is formulated around Carnosine and Squalane to soften the look of wrinkles and strengthen the skin barrier. This anti-aging

Medik8 Advanced Pro-Collagen+ Peptide Cream Versus Paula's Choice Pro-Collagen Peptide Plumping Moisturizer

This anti-aging moisturizer is formulated around Carnosine and Squalane to soften the look of wrinkles and strengthen the skin barrier.

This anti-aging moisturizer is formulated around Squalane to soften the look of wrinkles and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Squalane

Caprylic/Capric Triglyceride

Lavandula Angustifolia Flower Water

Glycerin

Dimethicone

Stearic Acid

Phytosteryl Oleate

C12-16 Alcohols

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Maltodextrin

Carnosine

Rosmarinus Officinalis Water

Cetearyl Alcohol

Butyrospermum Parkii Butter

Ceramide NP

Linoleic Acid

Cetearyl Olivate

Palmitic Acid

Behenyl Alcohol

Tocopheryl Acetate

Collagen Amino Acids

Micrococcus Lysate

Hydrogenated Lecithin

Oligopeptide-1

Sorbitan Olivate

Helianthus Annuus Sprout Extract

Xanthan Gum

Citric Acid

Sodium Hyaluronate

Ethylhexylglycerin

Sodium Gluconate

Sodium Polyglutamate

Acetyl Glucosamine

Hydroxyacetophenone

Phytosterols

Sodium Lauroyl Lactylate

Lecithin

Cholesterol

Ceteareth-25

Ceramide AP

Phytosphingosine

Carbomer

Cetyl Alcohol

Behenic Acid

Ceramide Ns

Ceramide EOP

Ceramide Eos

Caprooyl Phytosphingosine

Caprooyl Sphingosine

Phenoxyethanol

Ascorbyl Palmitate

Tocopherol

Glyceryl Stearate

Glyceryl Oleate

Water, Squalane, Caprylic/Capric Triglyceride, Lavandula Angustifolia Flower Water, Glycerin, Dimethicone, Stearic Acid, Phytosteryl Oleate, C12-16 Alcohols, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Maltodextrin, Carnosine, Rosmarinus Officinalis Water, Cetearyl Alcohol, Butyrospermum Parkii Butter, Ceramide NP, Linoleic Acid, Cetearyl Olivate, Palmitic Acid, Behenyl Alcohol, Tocopheryl Acetate, Collagen Amino Acids, Micrococcus Lysate, Hydrogenated Lecithin, Oligopeptide-1, Sorbitan Olivate, Helianthus Annuus Sprout Extract, Xanthan Gum, Citric Acid, Sodium Hyaluronate, Ethylhexylglycerin, Sodium Gluconate, Sodium Polyglutamate, Acetyl Glucosamine, Hydroxyacetophenone, Phytosterols, Sodium Lauroyl Lactylate, Lecithin, Cholesterol, Ceteareth-25, Ceramide AP, Phytosphingosine, Carbomer, Cetyl Alcohol, Behenic Acid, Ceramide Ns, Ceramide EOP, Ceramide Eos, Caprooyl Phytosphingosine, Caprooyl Sphingosine, Phenoxyethanol, Ascorbyl Palmitate, Tocopherol, Glyceryl Stearate, Glyceryl Oleate

Pyrus Malus Fruit Extract

Pentylene Glycol

1,2-Hexanediol

Ammonium Acryloyldimethyltaurate/Vp Copolymer

Butylene Glycol

Sodium Acrylates Copolymer

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Gigartina Stellata Extract

Acetyl Sh-Hexapeptide-5 Amide Acetate

Tridecapeptide-1

Sodium Phytate

Propanediol

Hydroxypropyltrimonium Hyaluronate

Cyanocobalamin

Water, Dimethicone, Squalane, Glycerin, Pyrus Malus Fruit Extract, Pentylene Glycol, 1,2-Hexanediol, Ammonium Acryloyldimethyltaurate/Vp Copolymer, Butylene Glycol, Hydroxyacetophenone, Sodium Acrylates Copolymer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Gigartina Stellata Extract, Acetyl Sh-Hexapeptide-5 Amide Acetate, Tridecapeptide-1, Oligopeptide-1, Sodium Phytate, Propanediol, Lecithin, Hydroxypropyltrimonium Hyaluronate, Cyanocobalamin, 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.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This 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.

Note: 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.

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.

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.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

Oligopeptide-1 is another name for Epidermal Growth Factor (EGF). In a formula, EGF works as a signaling ingredient.

EGF binds to receptors on your skin cells and tells keratinocytes/fibroblasts to divide, move, and rebuild the skin's support structure.

A 2012 open-label study on a barley-derived EGF serum reported statistically significant improvements in fine-lines, skin texture, pore size, and uneven skin tone, with changes showing up within the first month of 2x/daily use.

And a 2023 review found generally positive but modest results for growth factor products while pointing out that most trials are small, often industry-funded, and rarely test EGF on its own.

So, a fair summary of this ingredient would be "promising with real mechanistic backing, but not yet large-scale proof".

Concentration-wise, EGF is biologically active at very tiny amounts so finished products use it at low levels (think parts per million).

Raw material supplies usually sell a pre-diluted EGF solution and recommend adding roughly 1-5% of that solution to a formula.

Another practical catch: EGF is a fragile protein so it reacts badly to heat and the wrong pH. This just means it relies heavily on good packaging and a solid delivery system to stay active in a bottle.

Oligopeptide-1 and Sh-Oligopeptide-1. The "sh-" prefix just means "synthetic human" and it tells you that it's the lab grown version.

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.

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!

Similar Comparisons

The reference edit

Ingredients, questions
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Formula cabinet

Ingredients & structured notes

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Product index

Related product references

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Comparison edit

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