Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

IMAGE skincare Ormedic Balancing Bio-Peptide Crème Versus Kate Somerville KateCeuticals Total Repair Cream

IMAGE skincare Ormedic Balancing Bio-Peptide Crème Versus Kate Somerville KateCeuticals Total Repair Cream This calming moisturizer is formulated around Aloe Barbadensis Leaf Juice and Panthenol to calm redness and hydrate skin. This barrier-repair moisturizer

IMAGE skincare Ormedic Balancing Bio-Peptide Crème Versus Kate Somerville KateCeuticals Total Repair Cream

This calming moisturizer is formulated around Aloe Barbadensis Leaf Juice and Panthenol to calm redness and hydrate skin.

This barrier-repair moisturizer is formulated around Ceramide Ng and Cholesterol to strengthen the skin barrier and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Aloe Barbadensis Leaf Juice

Water

Glycerin

Vitis Vinifera Fruit Water

Olea Europaea Fruit Oil

Prunus Armeniaca Kernel Oil

Glyceryl Stearate

Cetearyl Alcohol

Stearic Acid

Simmondsia Chinensis Seed Oil

Dimethicone

Panthenol

Phenyl Trimethicone

Citrus Aurantium Dulcis Peel Oil

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Butyrospermum Parkii Butter

Mangifera Indica Seed Butter

Tocopheryl Acetate

Vitis Vinifera Seed Oil

Isohexadecane

Hydroxydecyl Ubiquinone

Polysorbate 80

Xanthan Gum

Caprylic/Capric Triglyceride

Cetyl Palmitate

Lactic Acid

Ethylhexylglycerin

Allantoin

Ascorbyl Palmitate

Tetrahexyldecyl Ascorbate

Aminomethyl Propanol

Sorbitan Stearate

Sorbitan Oleate

Citric Acid

Citrus Paradisi Peel Oil

Citrus Nobilis Peel Oil

Camellia Sinensis Leaf Extract

Palmitoyl Tripeptide-5

Sodium Hyaluronate

Arctium Lappa Root Extract

Calendula Officinalis Flower Extract

Curcuma Longa Root Extract

Nelumbo Nucifera Flower Extract

Tamarindus Indica Fruit Extract

Trifolium Pratense Flower Extract

Vanilla Planifolia Fruit

Hydrogenated Lecithin

Tocopherol

Palmitoyl Tetrapeptide-10

Phenoxyethanol

Sodium Benzoate

Potassium Sorbate

Limonene

Aloe Barbadensis Leaf Juice, Water, Glycerin, Vitis Vinifera Fruit Water, Olea Europaea Fruit Oil, Prunus Armeniaca Kernel Oil, Glyceryl Stearate, Cetearyl Alcohol, Stearic Acid, Simmondsia Chinensis Seed Oil, Dimethicone, Panthenol, Phenyl Trimethicone, Citrus Aurantium Dulcis Peel Oil, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Butyrospermum Parkii Butter, Mangifera Indica Seed Butter, Tocopheryl Acetate, Vitis Vinifera Seed Oil, Isohexadecane, Hydroxydecyl Ubiquinone, Polysorbate 80, Xanthan Gum, Caprylic/Capric Triglyceride, Cetyl Palmitate, Lactic Acid, Ethylhexylglycerin, Allantoin, Ascorbyl Palmitate, Tetrahexyldecyl Ascorbate, Aminomethyl Propanol, Sorbitan Stearate, Sorbitan Oleate, Citric Acid, Citrus Paradisi Peel Oil, Citrus Nobilis Peel Oil, Camellia Sinensis Leaf Extract, Palmitoyl Tripeptide-5, Sodium Hyaluronate, Arctium Lappa Root Extract, Calendula Officinalis Flower Extract, Curcuma Longa Root Extract, Nelumbo Nucifera Flower Extract, Tamarindus Indica Fruit Extract, Trifolium Pratense Flower Extract, Vanilla Planifolia Fruit, Hydrogenated Lecithin, Tocopherol, Palmitoyl Tetrapeptide-10, Phenoxyethanol, Sodium Benzoate, Potassium Sorbate, Limonene

Ceteareth-20

Isocetyl Stearoyl Stearate

Isopropyl Myristate

C12-15 Alkyl Benzoate

Cannabis Sativa Seed Oil

Orbignya Oleifera Seed Oil

Ceramide Ng

Cholesterol

Adenosine

Squalane

Macadamia Ternifolia Seed Oil

Copper PCA

Serica

Palmitoyl Hexapeptide-12

Triacetin

PEG-10 Phytosterol

Sodium PCA

Tribehenin

Urea

Polyquaternium-51

Butylene Glycol

Trehalose

Disodium EDTA

Parfum

Hexylene Glycol

BHT

Caprylyl Glycol

Chlorphenesin

Geraniol

Hexyl Cinnamal

Water, Cetearyl Alcohol, Dimethicone, Stearic Acid, Ceteareth-20, Glycerin, Isocetyl Stearoyl Stearate, Isopropyl Myristate, C12-15 Alkyl Benzoate, Cannabis Sativa Seed Oil, Caprylic/Capric Triglyceride, Orbignya Oleifera Seed Oil, Ceramide Ng, Cholesterol, Adenosine, Squalane, Macadamia Ternifolia Seed Oil, Copper PCA, Serica, Sodium Hyaluronate, Palmitoyl Hexapeptide-12, Allantoin, Simmondsia Chinensis Seed Oil, Citrus Paradisi Peel Oil, Ascorbyl Palmitate, Triacetin, PEG-10 Phytosterol, Sodium PCA, Tribehenin, Urea, Polyquaternium-51, Butylene Glycol, Trehalose, Potassium Sorbate, Sodium Benzoate, Disodium EDTA, Tocopheryl Acetate, Parfum, Hexylene Glycol, Lactic Acid, Aminomethyl Propanol, Xanthan Gum, BHT, Caprylyl Glycol, Chlorphenesin, Geraniol, Hexyl Cinnamal, Limonene

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Allantoin is a soothing ingredient known for its protective and moisturizing properties; it's basically a quiet workhorse ingredient you can find in a huge range of cosmetics.

Though it can be derived from the comfrey plant, allantoin is produced synthetically for cosmetic products to ensure purity.

Research shows it can encourage your skin cells to turn over and renew by stimulating keratinocyte and fibroblast proliferation.

It also has mild keratolytic properties to help loosen and shed dead skin cells without being harsh.

Studies also suggest allantoin can help calm inflammation by dialing down some of the chemical signals your skin sends out when it is irritated.

This ingredient is typically used in the 0.1-0.5% range, and the FDA recognizes it as a skin protectant in OTC products up to 2%.

Overall, allantoin is a wonderful addition to most routines; it is stable across a wide pH range (~4-8), works well with other ingredients, and is considered non-sensitizing/non-irritating.

Fun fact: Allantoin is naturally occurring in comfrey root, beets, chamomile, and wheat sprouts. Our bodies even produce it as a byproduct of uric acid metabolism.

Aminomethyl Propanol is used to adjust the pH of products. It is also used as a base to create other organic compounds. Having a balanced pH is important for protecting your skin.

Aminomethyl propanol is safe to use in cosmetics up to 1%. It is soluble in water.

Ascorbyl Palmitate is a fat-soluble form of vitamin C (Ascorbic Acid) made by combining it with palmitic acid.

It is able to blend easily into creams and oil-based formulas because it dissolves in oils rather than water.

As you may know, regular vitamin C is notorious for breaking down when exposed to sunlight and air. Ascorbyl Palmitate is more stable and degrades at a slower rate.

Research on whether it converts efficiently into active vitamin C once it's applied on your skin is still limited.

Some in-vitro studies suggest it may support collagen production, but it is not considered one of the stronger vitamin C derivatives, like:

Due to the palmitic acid base, this ingredient may not be fungal acne safe. Comedogenic studies have also shown this ingredient to have a rating of 2.

It's also worth keeping in mind that comedogenic and irritancy ratings are tested on individual ingredients, not finished formulas. The final product's formulation, concentration, and other ingredients all play a role in how something actually behaves on your skin.

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

This ingredient is also known as grapefruit peel oil. It is mainly used as a fragrance/perfuming ingredient and is made up of about 99-92% limonene.

Though in vitro or food science has shown this oil to be antibacterial, possess antioxidant activity, and be anti-inflammatory, there's very little research testing it directly on human skin or in cosmetics.

Limonene is a known skin sensitizer. Because grapefruit peel oil can contain furanocoumarins, this ingredient can also cause phototoxicity. It is possible to created furanocoumarin-free versions that are not phototoxic; it is best to reach out to the brand if you have questions about this ingredient in your cosmetics.

Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.

What it does:

Dimethicone comes in different viscosities:

Depending on the viscosity, dimethicone has different properties.

Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.

This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.

Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.

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.

Lactic Acid is another well-loved alpha hydroxy acid (AHA). It is gentler than glycolic acid but still highly effective.

Its main role is to exfoliate the surface of the skin by loosening the “glue” that holds dead skin cells together. Shedding those old cells leads to smoother, softer, and more even-toned skin.

Because lactic acid molecules are larger than glycolic acid, they don’t penetrate as deeply. This means they’re less likely to sting or irritate, making it a great choice for beginners or those with sensitive skin.

Like glycolic acid, it can:

Lactic acid also acts as a humectant (like hyaluronic acid). It can draw water into the skin to improve hydration and also plays a role in the skin's natural moisturizing factor (NMF) in the form of sodium lactate.

Studies show it can boost ceramide production to strengthen the skin barrier and even help balance the skin’s microbiome.

To get results, choose products with a pH between 3-4.

Lower strengths (5-12%) focus on surface exfoliation; higher strengths (12% and up) can reach deeper in the dermis (deeper, supportive layer) to improve skin texture and firmness over time.

Though it was originally derived from milk, most modern lactic acid used in skincare is vegan. It is made through non-dairy fermentation to create a bio-identical and stable form suitable for all formulations.

When lactic acid shows up near the end of an ingredient list, it usually means the brand added just a tiny amount to adjust the product’s pH.

Legend has it that Cleopatra used to bathe in sour milk to help reduce wrinkles.

Lactic acid is truly a gentle multitasker: it exfoliates, hydrates, strengthens, and brightens. It's a great ingredient for giving your skin a smooth, glowing, and healthy look without the harshness of stronger acids.

Read more about some other popular AHA's here:

Limonene is a fragrance that adds scent and taste to a formulation.

It's found in the peel oil of citrus fruits and other plants such as lavender and eucalyptus. The scent of limonene is generally described as "sweet citrus".

Limonene acts as an antioxidant, meaning it helps neutralize free radicals.

When exposed to air, oxidized limonene may sensitize the skin. Because of this, limonene is often avoided by people with sensitive skin.

The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.

Potassium Sorbate is a preservative used to prevent yeast and mold in products. It is commonly found in both cosmetic and food products.

This ingredient comes from potassium salt derived from sorbic acid. Sorbic acid is a natural antibiotic and effective against fungus.

Both potassium sorbate and sorbic acid can be found in baked goods, cheeses, dried meats, dried fruit, ice cream, pickles, wine, yogurt, and more.

You'll often find this ingredient used with other preservatives.

Jojoba oil is one of the most well-studied plant-derived ingredients in cosmetics. It is an emollient with a special structure.

Because it is made up of 97-98% wax esters, it closely mirrors the linear monoesters found in human sebum. This makes it skin compatible, non-greasy, and lightweight.

Unlike other plant oils, jojoba wax doesn't easily penetrate skin. It mostly works in the uppermost layers as an emollient. This just means it forms a light barrier on the skin to help retain moisture.

Formulations with jojoba esters up to 90% reduced transepidermal water loss (TEWL) and increased barrier recovery by 81% (outperforming bisabolol at 47%).

Besides barrier support, the science also suggests jojoba to have anti-inflammatory effects and potential applications for skin infections, aging, and wound healing.

Fun fact: Indigenous cultures have used jojoba as a moisturizer and to help treat burns for centuries.

Fungal acne: The Malassezia yeast is known to metabolize fatty acids in the C11-24 range and jojoba's dominant fatty acid components fall into this range. This ingredient 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.

Stearic Acid is a fatty acid that is already found in your skin. It's one of the free fatty acids that works alongside ceramides and cholesterols to maintain your barrier.

In cosmetics, it is a multitasker:

Safety-wise, the CIR Expert Panel has concluded it to be safe in cosmetics when formulated to be non-irritating and non-sensitizing.

Free stearic acid is a C18 fatty acid that the Malassezia yeast can substrate, so this ingredient may not be fungal acne safe.

Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.

Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.

It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.

One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.

Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.

Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.

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.

Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.

The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.

Most leave-on skincare keeps it at the lower end, often between 0.5-1%.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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