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L'Oreal Revitalift Laser Tri-Peptide Serum Versus Medik8 Liquid Peptides

L'Oreal Revitalift Laser Tri-Peptide Serum Versus Medik8 Liquid Peptides This anti-aging serum is formulated around Bifida Ferment Lysate and Acetyl Hexapeptide-8 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated aroun

L'Oreal Revitalift Laser Tri-Peptide Serum Versus Medik8 Liquid Peptides

This anti-aging serum is formulated around Bifida Ferment Lysate and Acetyl Hexapeptide-8 to soften the look of wrinkles and refine skin texture.

This anti-aging serum is formulated around Carnosine 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

Bifida Ferment Lysate

Glycerin

Alcohol Denat.

Polyglyceryl-4 Caprate

Sodium Hyaluronate

Betaine

Acetyl Dipeptide-1 Cetyl Ester

Acetyl Hexapeptide-8

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Phytic Acid

Secale Cereale Seed Extract

Sodium Acetylated Hyaluronate

Sodium Hydroxide

Trisodium Ethylenediamine Disuccinate

Ascorbyl Glucoside

Calcium Pantothenate

Isononyl Isononanoate

Isopropyl Myristate

Polyglyceryl-2 Isostearate

Acetic Acid

Ammonium Polyacryloyldimethyl Taurate

Butylene Glycol

Caprylyl Glycol

Carbomer

Hydroxyethylcellulose

Hydroxypropyl Methylcellulose

Lactic Acid

Pentylene Glycol

Polyepsilon-Lysine

Polysorbate 20

PPG-6-Decyltetradeceth-30

Sodium Lactate

Sorbitan Laurate

Tocopherol

Simethicone

Benzyl Alcohol

Citronellol

Linalool

Chlorphenesin

Sodium Benzoate

Parfum

Water, Bifida Ferment Lysate, Glycerin, Alcohol Denat., Polyglyceryl-4 Caprate, Sodium Hyaluronate, Betaine, Acetyl Dipeptide-1 Cetyl Ester, Acetyl Hexapeptide-8, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Phytic Acid, Secale Cereale Seed Extract, Sodium Acetylated Hyaluronate, Sodium Hydroxide, Trisodium Ethylenediamine Disuccinate, Ascorbyl Glucoside, Calcium Pantothenate, Isononyl Isononanoate, Isopropyl Myristate, Polyglyceryl-2 Isostearate, Acetic Acid, Ammonium Polyacryloyldimethyl Taurate, Butylene Glycol, Caprylyl Glycol, Carbomer, Hydroxyethylcellulose, Hydroxypropyl Methylcellulose, Lactic Acid, Pentylene Glycol, Polyepsilon-Lysine, Polysorbate 20, PPG-6-Decyltetradeceth-30, Sodium Lactate, Sorbitan Laurate, Tocopherol, Simethicone, Benzyl Alcohol, Citronellol, Linalool, Chlorphenesin, Sodium Benzoate, Parfum

Inulin

Panthenol

Alpha-Glucan Oligosaccharide

Carnosine

Phenoxyethanol

Hydroxypropyl Cyclodextrin

Dunaliella Salina Extract

Ethylhexylglycerin

Citric Acid

Palmitoyl Tripeptide-5

Tetrapeptide-21

Pentapeptide-18

Pantolactone

Palmitoyl Tripeptide-38

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

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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.

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.

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).

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.

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.

Palmitoyl Tetrapeptide-7 (formerly Palmitoyl Tetrapeptide-3) is a synthetic peptide. Its main job is to fight what researchers call "inflammaging".

"Inflammaging" is the slow, low-grade chronic inflammation that quietly breaks down collagen as we age.

This ingredient calms down a specific inflammation signal in your skin cells (called IL-6). When left unchecked, this signal triggers enzymes that break down collagen and elastin.

Clinical testing showed statistically significant improvements in:

Studies also found the more of this ingredient used, the more your skin produces Collagen I, fibronectin, and hyaluronic acid.

You'll likely see this ingredient paired with Palmitoyl Tripeptide-1 in the well-known Matrixyl 3000 complex for enhanced anti-aging effects.

A 3% concentration applied twice daily for two months showed meaningful skin rejuvenation results in clinical panels.

Fungal acne note: Usually a palmitic acid component can feed Malassezia in unbound form, but here is is covalently bonded to the peptide. This means it is very difficult for Malassezia to access, and therefore very unlikely to cause fungal acne.

Palmitoyl Tripeptide-1 (aka Pal-GHK) is a synthetic signal peptide made of three amino acids attached to palmitic acid.

That fatty acid attachment is the key: it boosts the peptide's ability to penetrate the skin barrier. This puts it closer to the dermal cells where it can actually make a difference.

Once there, it acts as a matrikine, a signaling peptide that prompts fibroblasts to produce more collagen, fibronectin, and hyaluronic acid.

In vitro studies show it can boost collagen production in skin cells even when UV-damaged skin samples were treated with it at a tiny concentration (it almost fully restored dermal collagen at 5ppm). It achieved this at 100x lower concentration than retinoic acid, which needed 500 ppm to do the same thing.

Human clinical data is promising, but modest:

A study of 23 female volunteers found a small but statistically significant increase (~4%) in skin thickness after treatment at 4 ppm.

A separate small trial of 15 women showed statistically significant reductions in wrinkle length, depth, and skin roughness after applying it twice daily for four weeks.

You'll likely see Pal-GHK paired with Palmitoyl Tetrapeptide-7 as part of the Matrixyl 3000 complex.

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 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 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. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though 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.
  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. 11Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
  12. 12There are two forms of panthenol: D and L.
  13. 13D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.
  14. 14Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):
  15. 15Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.
  16. 16This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.
  17. 17Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
  18. 18This ingredient is also referred to as pro-vitamin B5.
  19. 19Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  20. 20It 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.
Source · skinsort.com
02

Product index

Related product references

Product

Medik8 Liquid Peptides (2021)

Medik8 Liquid Peptides (2021) Medik8 Liquid Peptides (2021) ingredients explained: Aqua (Water), Glycerin, Butylene Glycol, Inulin, Sodium Hyaluronate, Panthenol, Alpha-Glucan Oligosacchari…

Source: incidecoder.comView reference →

Product

Medik8 Liquid Peptides

Medik8 Liquid Peptides Medik8 Liquid Peptides ingredients explained: Aqua (Water), Glycerin, Butylene Glycol, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1, Copper Heptapeptide-14 Pantot…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side