Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Bliss Bright Idea Serum Versus Bliss Pro Multi-Peptide Youth Face Serum

Bliss Bright Idea Serum Versus Bliss Pro Multi-Peptide Youth Face Serum This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Palmitoyl Tripeptide-5 to brighten dull-looking skin and soften the look of wrinkles. This anti-aging serum is formu

Bliss Bright Idea Serum Versus Bliss Pro Multi-Peptide Youth Face Serum

This brightening serum is formulated around 3-O-Ethyl Ascorbic Acid and Palmitoyl Tripeptide-5 to brighten dull-looking skin and soften the look of wrinkles.

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

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

3-O-Ethyl Ascorbic Acid

Propanediol

Palmitoyl Tripeptide-5

Sodium Hyaluronate

Tocopherol

Glycyrrhiza Glabra Root Extract

Pseudozyma Epicola/Camellia Japonica Seed Oil Ferment Extract Filtrate

Camellia Sinensis Seed Oil

Glucose

Bisabolol

Squalane

Hydrogenated Farnesene

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

C14-22 Alcohols

Polyacrylate Crosspolymer-6

Sodium Citrate

C12-20 Alkyl Glucoside

Xanthan Gum

Citric Acid

Dimethyl Isosorbide

Ethoxydiglycol

Glyceryl Stearate

Hydroxyacetophenone

Tetrasodium Glutamate Diacetate

Caprylyl Glycol

Polyglyceryl-4 Laurate/Succinate

Ethylhexylglycerin

Acacia Senegal Gum

Lecithin

Sclerotium Gum

Pullulan

Hexylene Glycol

Phenoxyethanol

Parfum

Limonene

Water, Glycerin, 3-O-Ethyl Ascorbic Acid, Propanediol, Palmitoyl Tripeptide-5, Sodium Hyaluronate, Tocopherol, Glycyrrhiza Glabra Root Extract, Pseudozyma Epicola/Camellia Japonica Seed Oil Ferment Extract Filtrate, Camellia Sinensis Seed Oil, Glucose, Bisabolol, Squalane, Hydrogenated Farnesene, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, C14-22 Alcohols, Polyacrylate Crosspolymer-6, Sodium Citrate, C12-20 Alkyl Glucoside, Xanthan Gum, Citric Acid, Dimethyl Isosorbide, Ethoxydiglycol, Glyceryl Stearate, Hydroxyacetophenone, Tetrasodium Glutamate Diacetate, Caprylyl Glycol, Polyglyceryl-4 Laurate/Succinate, Ethylhexylglycerin, Acacia Senegal Gum, Lecithin, Sclerotium Gum, Pullulan, Hexylene Glycol, Phenoxyethanol, Parfum, Limonene

Polysilicone-11

Palmitoyl Tripeptide-1

Palmitoyl Tetrapeptide-7

Palmitoyl Tripeptide-38

Acetyl Hexapeptide-8

Hexapeptide-9

Panthenol

Tocopheryl Acetate

Plankton Extract

Hippophae Rhamnoides Fruit Extract

Lycium Barbarum Fruit Extract

Helianthus Annuus Seed Oil

Arginine Ferulate

Raspberry Ketone

Cetearyl Olivate

Ubiquinone

Diglycerin

Saccharide Isomerate

Hydroxypropyl Cyclodextrin

C12-15 Alkyl Benzoate

Sorbitan Olivate

Carbomer

Polysorbate 20

Laureth-12

Butylene Glycol

Potassium Sorbate

Water, Propanediol, Glycerin, Polysilicone-11, Palmitoyl Tripeptide-1, Palmitoyl Tripeptide-5, Palmitoyl Tetrapeptide-7, Palmitoyl Tripeptide-38, Acetyl Hexapeptide-8, Hexapeptide-9, Panthenol, Tocopherol, Tocopheryl Acetate, Plankton Extract, Hippophae Rhamnoides Fruit Extract, Lycium Barbarum Fruit Extract, Helianthus Annuus Seed Oil, Arginine Ferulate, Sodium Hyaluronate, Raspberry Ketone, Cetearyl Olivate, Ubiquinone, Diglycerin, Saccharide Isomerate, Caprylyl Glycol, Hydroxypropyl Cyclodextrin, C12-15 Alkyl Benzoate, Polyacrylate Crosspolymer-6, Polyglyceryl-4 Laurate/Succinate, Sorbitan Olivate, Carbomer, Polysorbate 20, Laureth-12, Butylene Glycol, Sodium Citrate, Phenoxyethanol, Ethylhexylglycerin, Potassium Sorbate, Citric Acid

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

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.

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.

Palmitoyl Tripeptide-5 is a synthetic signal lipopeptide. This just means it is a three amino acid chain bolted onto a palmitic acid tail so it can slip through the skin's lipid barrier.

This peptide has a "build more, lose less" approach.

It's designed to mimic the collagen-stimulating activity in your skin by copying a snippet of one of your skin's own matrix proteins. This nudges fibroblasts into making more collagen while inhibiting the enzyme that breaks down skin protein.

The manufacturer's in vivo study of 45 volunteers found 1% and 2.5% reduced the appearance of wrinkles by 7% and 12% respectively, after using it twice daily for 84 days.

This is in the expected range for peptides; they're slow and cumulative actives and not overnight fixers.

Typical use levels range from 1-3% and this ingredient gets along with pretty much everything.

On the fungal acne front: Although palmitic acid sits in the chain length that Malassezia can feed on, this ingredient has it locked in an amine bond. This makes it hard for Malassezia to access as a source of food, and therefore fungal acne safe.

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.

Polyacrylate Crosspolymer-6 is a texture enhancer and pH adjuster.

It is be used to thicken water-based products and create a gel-texture with a velvet feel.

One manufacturer claims this ingredient to have a pH range of 2-8 and to be biodegradable.

This ingredient is also known as Sepimax Zen.

Polyglyceryl-4 Laurate/Succinate isn't fungal acne safe.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Sodium Citrate is the sodium salts of citric acid. In skincare, it is used to alter pH levels and acts as a preservative.

Its main functions are to maintain the pH of a product and neutralize metal ions.

The acidity of our skin is maintained by our glands and skin biome; normal pH level of skin is slightly acidic (~4.75-5.5).

Being slightly acidic allows our skin to create an "acid mantle". This acid mantle is a thin barrier that protects our skin from bacteria and contaminants.

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.

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. 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. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your 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.
  14. 14Aquaporin-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.
  15. 15This 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.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18This ingredient is used in skincare as a delivery system.
  19. 19It works by "encapsulating" active ingredients with its unique ring shape that is water-loving on the outside and oil-loving on the inside. This improves the stability and absorption of the product into the skin.
  20. 20According to a manufacturer, it also offer some moisturizing effects.
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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