Peptide Skincare & BeautySkin science and ingredient guides

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Medik8 Liquid Peptides Versus Nip + Fab Peptide Fix Finishing Oil 2%

Medik8 Liquid Peptides Versus Nip + Fab Peptide Fix Finishing Oil 2% 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 oil is formulated around Palmitoyl Trip

Medik8 Liquid Peptides Versus Nip + Fab Peptide Fix Finishing Oil 2%

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 oil is formulated around Palmitoyl Tripeptide-1 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

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

Orbignya Oleifera Seed Oil

Prunus Amygdalus Dulcis Oil

Vitis Vinifera Seed Oil

Adansonia Digitata Seed Oil

Passiflora Edulis Seed Oil

Cucurbita Pepo Seed Oil

Helianthus Annuus Seed Oil

Prunus Armeniaca Kernel Oil

Prunus Persica Kernel Oil

Bakuchiol

Copper Tripeptide-1

Sodium Hydroxide

Caprylic/Capric Triglyceride

Cetyl Ethylhexanoate

Gluconolactone

Limonene

Brassica Campestris Seed Oil

Polyglyceryl-3 Laurate

Glycyrrhiza Glabra Root Extract

Polyglyceryl-3 Diisostearate

Crithmum Maritimum Extract

Tocopherol

Althaea Officinalis Root Extract

Oryza Sativa Bran Extract

Methyl Glucose Sesquistearate

Citrus Nobilis Peel Oil Expressed

Calcium Gluconate

Ethylhexyl Palmitate

Linalool

Tribehenin

Sorbitan Isostearate

Water, Orbignya Oleifera Seed Oil, Prunus Amygdalus Dulcis Oil, Vitis Vinifera Seed Oil, Adansonia Digitata Seed Oil, Passiflora Edulis Seed Oil, Glycerin, Cucurbita Pepo Seed Oil, Helianthus Annuus Seed Oil, Prunus Armeniaca Kernel Oil, Prunus Persica Kernel Oil, Bakuchiol, Palmitoyl Tripeptide-1, Acetyl Hexapeptide-8, Copper Tripeptide-1, Sodium Hydroxide, Caprylic/Capric Triglyceride, Cetyl Ethylhexanoate, Gluconolactone, Limonene, Brassica Campestris Seed Oil, Sodium Benzoate, Polyglyceryl-3 Laurate, Glycyrrhiza Glabra Root Extract, Polyglyceryl-3 Diisostearate, Crithmum Maritimum Extract, Tocopherol, Althaea Officinalis Root Extract, Oryza Sativa Bran Extract, Methyl Glucose Sesquistearate, Citrus Nobilis Peel Oil Expressed, Calcium Gluconate, Ethylhexyl Palmitate, Linalool, Tribehenin, Sorbitan Isostearate

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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.

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 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.

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.

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.

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.

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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. 11Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  12. 12Like 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.
  13. 13However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  14. 14Due 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.
  15. 15In skincare formulas, citric acid can:
  16. 16While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  17. 17Most 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.
  18. 18Rosacea 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.
  19. 19However, 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…
  20. 20Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
Source · skinsort.com
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Comparison edit

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