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Skin science article

Allies of Skin Copper Tripeptide & Ectoin Advanced Repair Serum Versus Medik8 Liquid Peptides Advanced MP

Allies of Skin Copper Tripeptide & Ectoin Advanced Repair Serum Versus Medik8 Liquid Peptides Advanced MP This barrier-repair serum is formulated around Ectoin and Copper Tripeptide-1 to strengthen the skin barrier and soften the look of wrinkles. This anti-ag

Allies of Skin Copper Tripeptide & Ectoin Advanced Repair Serum Versus Medik8 Liquid Peptides Advanced MP

This barrier-repair serum is formulated around Ectoin and Copper Tripeptide-1 to strengthen the skin barrier and soften the look of wrinkles.

This anti-aging serum is formulated around Palmitoyl Tripeptide-38 and Palmitoyl Tripeptide-5 to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Ectoin

Polyglyceryl-10 Oleate

Coco-Caprylate/Caprate

Isononyl Isononanoate

Dimethyl Isosorbide

Panthenol

Carnitine

Tocopherol

Copper Tripeptide-1

Oxidized Glutathione

Ergothioneine

Tropolone

Copper Lysinate/Prolinate

Acetyl Hexapeptide-8

Methylglucoside Phosphate

Hydroxyethylcellulose

Saccharide Isomerate

Ethylhexylglycerin

Sodium Gluconate

Sclerotium Gum

Disodium Phosphate

Sodium Phosphate

Caprylyl Glycol

Propanediol

1,2-Hexanediol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Citric Acid

Polysorbate 60

Sodium Hydroxide

Polysorbate 20

Phenoxyethanol

Water, Glycerin, Ectoin, Polyglyceryl-10 Oleate, Coco-Caprylate/Caprate, Isononyl Isononanoate, Dimethyl Isosorbide, Panthenol, Carnitine, Tocopherol, Copper Tripeptide-1, Oxidized Glutathione, Ergothioneine, Tropolone, Copper Lysinate/Prolinate, Acetyl Hexapeptide-8, Methylglucoside Phosphate, Hydroxyethylcellulose, Saccharide Isomerate, Ethylhexylglycerin, Sodium Gluconate, Sclerotium Gum, Disodium Phosphate, Sodium Phosphate, Caprylyl Glycol, Propanediol, 1,2-Hexanediol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Citric Acid, Polysorbate 60, Sodium Hydroxide, Polysorbate 20, Phenoxyethanol

Dimethicone

Butylene Glycol

Undecane

Arginine

Inulin

Microcrystalline Cellulose

Ceteareth-20

Tridecane

Hydroxyacetophenone

Sodium Hyaluronate

Palmitoyl Tripeptide-38

Caprylic/Capric Triglyceride

Palmitoyl Tripeptide-5

Polyacrylate Crosspolymer-6

Palmitoyl Tripeptide-1

Pullulan

Tetrapeptide-21

Palmitoyl Tetrapeptide-10

Palmitoyl Tetrapeptide-7

Ammonium Polyacryloyldimethyl Taurate

Glyceryl Linoleate

Pentapeptide-18

Oligopeptide-1

Arginine/Lysine Polypeptide

Sucrose Palmitate

Cetyl Palmitate

Carbomer

Copper Palmitoyl Heptapeptide-14

Heptapeptide-15 Palmitate

Benzotriazolyl Dodecyl P-Cresol

Polysorbate 80

Sorbitan Stearate

Carnosine

Sodium Metabisulfite

Dunaliella Salina Extract

Helianthus Annuus Seed Oil

Hydroxypropyl Cyclodextrin

Dimethicone/Vinyl Dimethicone Crosspolymer

Sodium Benzoate

Hydrogenated Lecithin

Pantolactone

Xanthan Gum

Disodium EDTA

T-Butyl Alcohol

Potassium Sorbate

Glyceryl Caprylate

Lactic Acid/Glycolic Acid Copolymer

Polyvinyl Alcohol

Phenylpropanol

Water, Glycerin, Dimethicone, Dimethyl Isosorbide, Butylene Glycol, Undecane, Arginine, Inulin, Microcrystalline Cellulose, Ceteareth-20, Tridecane, Tocopherol, Hydroxyacetophenone, Sodium Hyaluronate, Palmitoyl Tripeptide-38, Panthenol, Caprylic/Capric Triglyceride, Palmitoyl Tripeptide-5, Polyacrylate Crosspolymer-6, Palmitoyl Tripeptide-1, Pullulan, Tetrapeptide-21, Palmitoyl Tetrapeptide-10, Palmitoyl Tetrapeptide-7, Ammonium Polyacryloyldimethyl Taurate, Glyceryl Linoleate, Acetyl Hexapeptide-8, Pentapeptide-18, Oligopeptide-1, Arginine/Lysine Polypeptide, Sucrose Palmitate, Cetyl Palmitate, Phenoxyethanol, Ethylhexylglycerin, Carbomer, Copper Palmitoyl Heptapeptide-14, Heptapeptide-15 Palmitate, Benzotriazolyl Dodecyl P-Cresol, Polysorbate 80, Sorbitan Stearate, Polysorbate 20, Carnosine, Sodium Metabisulfite, Dunaliella Salina Extract, Helianthus Annuus Seed Oil, Hydroxypropyl Cyclodextrin, Dimethicone/Vinyl Dimethicone Crosspolymer, Sodium Benzoate, Hydrogenated Lecithin, Caprylyl Glycol, Pantolactone, Xanthan Gum, Disodium EDTA, T-Butyl Alcohol, Potassium Sorbate, Citric Acid, Glyceryl Caprylate, Lactic Acid/Glycolic Acid Copolymer, Polyvinyl Alcohol, Phenylpropanol

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.

Acetyl Hexapeptide-8 (also known as Argireline) is a synthetic hexapeptide that is often called a "topical Botox alternative".

It works by mimicking how Botox relaxes muscles; it interferes with the signaling process that tells your facial muscles to contract. This can help soften expression lines like forehead wrinkles or crow's feet over time.

The comparison to Botox does have limits because the molecule is water-loving and relatively large.

Acetyl Hexapeptide-8 has a hard time absorbing deeply enough through the skin's outer barrier to actually reach the muscles.

So whether it truly works the way Botox does at a biological level is still up for debate, but early clinical outcomes are fairly encouraging.

A 12 week human study of a multi-ingredient regimen containing this ingredient saw:

While some studies have observed improvements in wrinkle appearance, it is important to note that more consistent results are seen in multi-ingredient formulations (vs just Acetyl Hexapeptide-8 alone).

Some research studies also used higher concentrations (up to 10%) while this ingredient is usually found in concentrations up to 0.005% in leave-on formulations.

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).

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.

Dimethyl Isosorbide (often shortened to DMI) is a sugar-derived solvent made from sorbitol. It's used to dissolve tricky ingredients and help them mix smoothly into a formula.

Many actives sit as gritty crystals when undissolved, so DMI swoops in to full dissolve them. This helps improve texture, stability, and how evenly an active is distributed.

It does have a penetration-enhancing reputation that is a bit more nuanced than marketing suggests; a cell study on human skin found that 10% DMI didn't significantly boost the permeation of Hydroquinone, Salicylic Acid, or Octadecenedioic Acid compared to controls (though it did improve their solubility in the formula itself).

Typical usage concentrations usually range from 1-10% depending on the formula's needs; this ingredient is also well tolerated at these levels.

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.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

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.

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. 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. 06Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  7. 07It 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.
  8. 08On 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.
  9. 09Another perk of this ingredient is that it stays functional across a wide pH range (3-10).
  10. 10You'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.
  11. 11Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.
  12. 12Safety-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.
  13. 13Adverse 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.
  14. 14Tetrahexyldecyl Ascorbate (THD) is a stable and oil-soluble form of Vitamin C.
  15. 15THD is special in that it has the ability to travel deeper into skin than traditional ascorbic acid while maintaining the same skin benefits (double win!).
  16. 16Because it’s oil-soluble, THD dives deep into your skin’s fatty layers (think ceramides and cholesterol) to fight off the kind of free radicals that mess with your skin barrier. This makes it a great pair with water-based vitamin C (ascorbic acid) t…
  17. 17Even at just 0.1%, THD is already showing great antioxidant activity. When used up to 2%, it helps keep your skin happy and calm, especially when it’s stressed from pollution or sun.
  18. 18Want to fade dark spots or tackle hyperpigmentation? You’ll want 5% or more. Pairing it with brightening buddies like niacinamide or licorice root gives even better results. One study even used 30% THD with other brighteners and saw real results on …
  19. 19A note on THD: It’s has a slightly silky, oily texture and usually shows up colorless or pale yellow (though the exact shade can vary by supplier).
  20. 20While you can sneak it into water-based formulas, it really shines when paired with silicones or oils, which help your skin soak it up better.
Source · skinsort.com
02

Product index

Related product references

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Allies of Skin Dew Halo Glow Mist

Allies of Skin Dew Halo Glow Mist Allies of Skin Dew Halo Glow Mist ingredients explained: Aqua (Water), Niacinamide, Glycerin, Propanediol, Caprylyl Glycol, Leuconostoc/Radish Root Ferment…

Source: incidecoder.comView reference →

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Allies of Skin 1A Overnight Mask

Allies of Skin 1A Overnight Mask Allies of Skin 1A Overnight Mask ingredients explained: Aqua (Water), Glycerin, Caprylic/Capric Triglyceride, Propanediol, Argania Spinosa Kernel Oil (Organ…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side