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Skin science article

ZO Skin Health Daily Power Defense Versus Medik8 Liquid Peptides

ZO Skin Health Daily Power Defense Versus Medik8 Liquid Peptides This barrier-repair moisturizer is formulated around Laminaria Digitata Extract and Beta-Glucan to strengthen the skin barrier and hydrate skin. This anti-aging serum is formulated around Carnosi

ZO Skin Health Daily Power Defense Versus Medik8 Liquid Peptides

This barrier-repair moisturizer is formulated around Laminaria Digitata Extract and Beta-Glucan to strengthen the skin barrier and hydrate skin.

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

Dicaprylyl Carbonate

Cetearyl Isononanoate

Glycerin

Pentylene Glycol

Cetearyl Alcohol

Steareth-20

Safflower Oil/Palm Oil Aminopropanediol Esters

Laminaria Digitata Extract

Opuntia Ficus-Indica Stem Extract

Arabidopsis Thaliana Extract

Marrubium Vulgare Meristem Cell Culture

Leontopodium Alpinum Meristem Cell Culture

Retinyl Palmitate

Tocopheryl Acetate

Tocopherol

Micrococcus Lysate

Caprylyl Glycol

Hexylene Glycol

Lactose

Galactoarabinan

Lecithin

Schizophyllan

Beta-Glucan

1,2-Hexanediol

Carbomer

Cellulose

Maltodextrin

C14-22 Alcohols

Cetearyl Glucoside

C12-20 Alkyl Glucoside

Hydroxypropyl Methylcellulose

Disodium EDTA

Sodium Hydroxide

Phenoxyethanol

Ethylhexylglycerin

Sodium Benzoate

Parfum

CI 77007

Limonene

Water, Dicaprylyl Carbonate, Cetearyl Isononanoate, Glycerin, Pentylene Glycol, Cetearyl Alcohol, Steareth-20, Safflower Oil/Palm Oil Aminopropanediol Esters, Laminaria Digitata Extract, Opuntia Ficus-Indica Stem Extract, Arabidopsis Thaliana Extract, Marrubium Vulgare Meristem Cell Culture, Leontopodium Alpinum Meristem Cell Culture, Retinyl Palmitate, Tocopheryl Acetate, Tocopherol, Micrococcus Lysate, Caprylyl Glycol, Hexylene Glycol, Lactose, Galactoarabinan, Lecithin, Schizophyllan, Beta-Glucan, 1,2-Hexanediol, Carbomer, Cellulose, Maltodextrin, C14-22 Alcohols, Cetearyl Glucoside, C12-20 Alkyl Glucoside, Hydroxypropyl Methylcellulose, Disodium EDTA, Sodium Hydroxide, Phenoxyethanol, Ethylhexylglycerin, Sodium Benzoate, Parfum, CI 77007, Limonene

Butylene Glycol

Inulin

Sodium Hyaluronate

Panthenol

Alpha-Glucan Oligosaccharide

Carnosine

Polysorbate 20

Hydroxypropyl Cyclodextrin

Dunaliella Salina Extract

Citric Acid

Palmitoyl Tripeptide-5

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

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.

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.

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.

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.

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.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Dimethicone
  3. 03Glycerin
  4. 04Methyl Trimethicone
  5. 05Bis-PEG-18 Methyl Ether Dimethyl Silane
  6. 06Butylene Glycol
  7. 07Isopropyl Isostearate
  8. 08PPG-15 Stearyl Ether
  9. 09PEG-10 Dimethicone
  10. 10Faex Extract
  11. 11Tripeptide-32
  12. 12Sodium Hyaluronate Crosspolymer
  13. 13Sodium Hyaluronate
  14. 14Hydrolyzed Sodium Hyaluronate
  15. 15Hydrolyzed Algin
  16. 16Lactobacillus Ferment
  17. 17Adansonia Digitata Seed Extract
  18. 18Soy Amino Acids
  19. 19Aminopropyl Ascorbyl Phosphate
  20. 20Resveratrol
Source · skinsort.com
02

Product index

Related product references

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Medik8 Liquid Peptides

Medik8 Liquid Peptides Ingredients in Medik8 Liquid Peptides explained: benefits, concerns, and detailed analysis of 33 ingredients including Water, Glycerin, and Butylene Glycol A highly r…

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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 →
03

Comparison edit

Read side by side