Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

The INKEY List Collagen Booster Versus The Ordinary "Buffet"

The INKEY List Collagen Booster Versus The Ordinary "Buffet" This anti-aging serum is formulated around Palmitoyl Tetrapeptide-7 and Palmitoyl Tripeptide-1 to soften the look of wrinkles and refine skin texture. This anti-aging serum is formulated around Lacto

The INKEY List Collagen Booster Versus The Ordinary "Buffet"

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

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Butylene Glycol

Propanediol

Phenoxyethanol

Hydroxyethylcellulose

Disodium EDTA

Leuconostoc/Radish Root Ferment Filtrate

Carbomer

Hyaluronic Acid

Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine

Palmitoyl Dipeptide-5 Diaminohydroxybutyrate

Polysorbate 20

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-1

Water, Glycerin, Butylene Glycol, Propanediol, Phenoxyethanol, Hydroxyethylcellulose, Disodium EDTA, Leuconostoc/Radish Root Ferment Filtrate, Carbomer, Hyaluronic Acid, Palmitoyl Dipeptide-5 Diaminobutyroyl Hydroxythreonine, Palmitoyl Dipeptide-5 Diaminohydroxybutyrate, Polysorbate 20, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-1

Lactococcus Ferment Lysate

Acetyl Hexapeptide-8

Pentapeptide-18

Palmitoyl Tripeptide-38

Dipeptide Diaminobutyroyl Benzylamide Diacetate

Acetylarginyltryptophyl Diphenylglycine

Sodium Hyaluronate Crosspolymer

Sodium Hyaluronate

Allantoin

Glycine

Alanine

Serine

Valine

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Arginine

Aspartic Acid

Trehalose

Fructose

Glucose

Maltose

Urea

Sodium PCA

PCA

Sodium Lactate

Citric Acid

Hydroxypropyl Cyclodextrin

Sodium Chloride

Sodium Hydroxide

Pentylene Glycol

Acacia Senegal Gum

Xanthan Gum

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

Trisodium Ethylenediamine Disuccinate

Ethoxydiglycol

Sodium Benzoate

Caprylyl Glycol

Ethylhexylglycerin

Chlorphenesin

Water, Glycerin, Lactococcus Ferment Lysate, Acetyl Hexapeptide-8, Pentapeptide-18, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-38, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Acetylarginyltryptophyl Diphenylglycine, Sodium Hyaluronate Crosspolymer, Sodium Hyaluronate, Allantoin, Glycine, Alanine, Serine, Valine, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Arginine, Aspartic Acid, Trehalose, Fructose, Glucose, Maltose, Urea, Sodium PCA, PCA, Sodium Lactate, Citric Acid, Hydroxypropyl Cyclodextrin, Sodium Chloride, Sodium Hydroxide, Butylene Glycol, Pentylene Glycol, Acacia Senegal Gum, Xanthan Gum, Carbomer, Polysorbate 20, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Trisodium Ethylenediamine Disuccinate, Ethoxydiglycol, Sodium Benzoate, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol, Chlorphenesin

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.

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.

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.

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

The Inkey List Hydro-Surge Dewy Face MistIngredients explained

  1. 01Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product.
  2. 02It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water.
  3. 03Expand to read more
  4. 04Once inside the skin, it hydrates, but not from the outside - putting pure water on the skin (hello long baths!) is drying.
  5. 05One more thing: the water used in cosmetics is purified and deionized (it means that almost all of the mineral ions inside it is removed). Like this, the products can stay more stable over time.
  6. 06A natural moisturizer that’s also in our skin
  7. 07A super common, safe, effective and cheap molecule used for more than 50 years
  8. 08Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  9. 09Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  10. 10High-glycerin moisturizers are awesome for treating severely dry skin
  11. 11Cucumber is a nice, non-irritating plant extract that’s known for it’s soothing and emollient properties. It’s not something new to put it on our face: even Cleopatra used it to “preserve her skin”.
  12. 12It’s commonly believed that cucumber is the answer to puffy eyes, but there is no research confirming this. What research does confirm is that it contains amino acids and organic acids that’s helpful for the skin’s acid mantle. There is also an enzy…
  13. 13A sugar beet-derived amino acid derivative with nice skin protection and moisturization properties. Betaine's special thing is being an osmolyte, a molecule that helps to control cell-water balance. It is also a natural osmoprotectant, meaning that …
  14. 14It also gives sensorial benefits to the formula and when used in cleansers, it helps to make them milder and gentler.
  15. 15The main part of a moisturizing complex called Aquaxyl. Comes from two water-binding plant sugars, glucose and xylitol. According to the manufacturer, Aquaxyl is close to a magic moisturizer that not only simply moisturizes, but can "harmonize the s…
  16. 16This means that on the one side it can optimize water reserves by increasing important NMFs (natural moisturizing factors - things that are naturally in the skin and help to keep it hydrated) - like hyaluronic acid and chondroitin sulfate - in the s…
  17. 17In vivo (made on real people) tests show that 3% Aquaxyl not only increases the water content of the outer layer instantly and in the long run but it also visibly improves cracked, dry skin and smoothes the skin surface after a month of treatment.
  18. 18The hydrating effect of Aquaxyl was also examined in a comparative study in the Journal of Cosmetic Dermatology. Four humectants were examined in combination with 5% glycerin in a hydrogel formula and one with 4% Aquaxyl performed as well as the wel…
  19. 19All in all, Aquaxyl is a goodie and if you have dehydrated, dry skin it's something to look at.
  20. 20We don't have description for this ingredient yet.
Source · incidecoder.com
02

Product index

Related product references

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03

Comparison edit

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