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Medik8 Liquid Peptides Versus PCA Skin Pro-Max Age Renewal Advanced Serum

Medik8 Liquid Peptides Versus PCA Skin Pro-Max Age Renewal Advanced Serum This anti-aging serum is formulated around Carnosine and Palmitoyl Tripeptide-5 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Sodium

Medik8 Liquid Peptides Versus PCA Skin Pro-Max Age Renewal Advanced Serum

This anti-aging serum is formulated around Carnosine and Palmitoyl Tripeptide-5 to soften the look of wrinkles and refine skin texture.

This anti-aging serum is formulated around Sodium Hyaluronate and Acetyl Octapeptide-3 to soften the look of wrinkles and hydrate skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Butylene Glycol

Inulin

Sodium Hyaluronate

Panthenol

Alpha-Glucan Oligosaccharide

Carnosine

Carbomer

Polysorbate 20

Caprylyl Glycol

Phenoxyethanol

Hydroxypropyl Cyclodextrin

Dunaliella Salina Extract

Ethylhexylglycerin

Citric Acid

Palmitoyl Tripeptide-5

Sodium Benzoate

Acetyl Hexapeptide-8

Tetrapeptide-21

Pentapeptide-18

Palmitoyl Tripeptide-1

Pantolactone

Palmitoyl Tripeptide-38

Palmitoyl Tetrapeptide-7

Glyceryl Caprylate

Lactic Acid/Glycolic Acid Copolymer

Polyvinyl Alcohol

Phenylpropanol

Copper Palmitoyl Heptapeptide-14

Heptapeptide-15 Palmitate

Potassium Sorbate

Xanthan Gum

Water, Glycerin, Butylene Glycol, Inulin, Sodium Hyaluronate, Panthenol, Alpha-Glucan Oligosaccharide, Carnosine, Carbomer, Polysorbate 20, Caprylyl Glycol, Phenoxyethanol, Hydroxypropyl Cyclodextrin, Dunaliella Salina Extract, Ethylhexylglycerin, Citric Acid, Palmitoyl Tripeptide-5, Sodium Benzoate, Acetyl Hexapeptide-8, Tetrapeptide-21, Pentapeptide-18, Palmitoyl Tripeptide-1, Pantolactone, Palmitoyl Tripeptide-38, Palmitoyl Tetrapeptide-7, Glyceryl Caprylate, Lactic Acid/Glycolic Acid Copolymer, Polyvinyl Alcohol, Phenylpropanol, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Potassium Sorbate, Xanthan Gum

Polysilicone-11

Propanediol

PPG-3 Benzyl Ether Myristate

Sodium Polyacryloyldimethyl Taurate

Hydroxypropyl Methylcellulose

Ethylene Brassylate

Pullulan

Hydrolyzed Hyaluronic Acid

Sodium Acetylated Hyaluronate

Lactic Acid

Laureth-12

Tricholoma Matsutake Extract

Hdi/Trimethylol Hexyllactone Crosspolymer

Polymethylsilsesquioxane

Anigozanthos Flavidus Extract

Porphyridium Cruentum Extract

Pentylene Glycol

Bacillus Ferment

Sodium Hyaluronate Crosspolymer

Acetyl Octapeptide-3

Acetyl Tripeptide-54 Amide

Acetyl Tripeptide-74 Amide

Palmitoyl Sh-Tripeptide-1 Amide

Palmitoyl Sh-Tripeptide-3 Amide

Ergothioneine

Water, Polysilicone-11, Propanediol, Glycerin, Butylene Glycol, PPG-3 Benzyl Ether Myristate, Polysorbate 20, Sodium Polyacryloyldimethyl Taurate, Caprylyl Glycol, Sodium Benzoate, Hydroxypropyl Methylcellulose, Sodium Hyaluronate, Ethylene Brassylate, Pullulan, Hydrolyzed Hyaluronic Acid, Potassium Sorbate, Sodium Acetylated Hyaluronate, Lactic Acid, Laureth-12, Carnosine, Tricholoma Matsutake Extract, Phenoxyethanol, Hdi/Trimethylol Hexyllactone Crosspolymer, Polymethylsilsesquioxane, Anigozanthos Flavidus Extract, Porphyridium Cruentum Extract, Pentylene Glycol, Ethylhexylglycerin, Bacillus Ferment, Sodium Hyaluronate Crosspolymer, Acetyl Octapeptide-3, Acetyl Tripeptide-54 Amide, Acetyl Tripeptide-74 Amide, Palmitoyl Sh-Tripeptide-1 Amide, Palmitoyl Sh-Tripeptide-3 Amide, Ergothioneine

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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.

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.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

Carnosine is a dipeptide made from two amino acids.

This ingredient helps:

Glycation is the process of sugars binding to and damaging proteins. Too much sugar in our skin can lead to damaged collagen, contributing to factors of aging.

Carnosine is water-soluble and is not able to travel deeper layers of skin. This leads to some doubt about whether it can boost collagen in skin, since collagen is located in the deeper layers of skin.

Fun fact: Carnosine can be naturally found in our muscles and brain.

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.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Sodium Benzoate is a preservative. It's used in both cosmetic and food products to inhibit the growth of mold and bacteria. It is typically produced synthetically.

Both the US FDA and EU Health Committee have approved the use of sodium benzoate. In the US, levels of 0.1% (of the total product) are allowed.

Sodium benzoate works as a preservative by inhibiting the growth of bacteria inside of cells. It prevents the cell from fermenting a type of sugar using an enzyme called phosphofructokinase.

It is the salt of benzoic acid. Foods containing sodium benzoate include soda, salad dressings, condiments, fruit juices, wines, and snack foods.

Studies for using ascorbic acid and sodium benzoate in cosmetics are lacking, especially in skincare routines with multiple steps.

We always recommend speaking with a professional, such as a dermatologist, if you have any concerns.

Sodium Hyaluronate is the salt form of hyaluronic acid. It is a long sugar chain that is naturally found in your skin, joints, and connective tissue that maintains hydration and elasticity.

In skincare, it works as a humectant. It pulls water from the environment and deeper layers of skin and binds it to the surface.

Interestingly, the size of the molecule affects its behavior:

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

Many serums use a blend of both weights so you can get surface hydration plus longer-lasting and deeper effects.

You'll typically see concentrations between 0.1-2% for this ingredient.

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 Side-by-side

  1. 01Water
  2. 02Glycerin
  3. 03Butylene Glycol
  4. 04Inulin
  5. 05Sodium Hyaluronate
  6. 06Panthenol
  7. 07Alpha-Glucan Oligosaccharide
  8. 08Carnosine
  9. 09Carbomer
  10. 10Polysorbate 20
  11. 11Caprylyl Glycol
  12. 12Phenoxyethanol
  13. 13Hydroxypropyl Cyclodextrin
  14. 14Dunaliella Salina Extract
  15. 15Ethylhexylglycerin
  16. 16Citric Acid
  17. 17Palmitoyl Tripeptide-5
  18. 18Sodium Benzoate
  19. 19Acetyl Hexapeptide-8
  20. 20Tetrapeptide-21
Source · skinsort.com
02

Product index

Related product references

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03

Comparison edit

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