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Medik8 Crystal Retinal Versus Estée Lauder Advanced Night Repair Synchronized Recovery Complex II

Medik8 Crystal Retinal Versus Estée Lauder Advanced Night Repair Synchronized Recovery Complex II This anti-aging serum is formulated around 3-O-Ethyl Ascorbic Acid and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture. This barr

Written by Peptide Therapy Guide Editorial Team
For education only

This guide cannot diagnose a condition or recommend a personal treatment plan. Discuss medical questions with a qualified professional.

Medik8 Crystal Retinal Versus Estée Lauder Advanced Night Repair Synchronized Recovery Complex II

This anti-aging serum is formulated around 3-O-Ethyl Ascorbic Acid and Tetrahexyldecyl Ascorbate to soften the look of wrinkles and refine skin texture.

This barrier-repair serum is formulated around Bifida Ferment Lysate to strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Caprylic/Capric Triglyceride

Glycerin

Isododecane

Cetearyl Olivate

Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Cetearyl Alcohol

PPG-12/Smdi Copolymer

Sorbitan Olivate

Tocopheryl Acetate

Cyclodextrin

Squalane

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Hydroxyacetophenone

3-O-Ethyl Ascorbic Acid

Hydroxypropyl Methylcellulose

Sodium Hyaluronate

Phenoxyethanol

Tetrahexyldecyl Ascorbate

Daucus Carota Sativa Seed Oil

Retinal

Rubus Chamaemorus Seed Oil

Alumina

Isostearic Acid

Lecithin

Polyglyceryl-3 Polyricinoleate

Lonicera Japonica Flower Extract

Lonicera Caprifolium Flower Extract

Polyhydroxystearic Acid

Stearic Acid

Sodium Polyaspartate

Pentylene Glycol

Citric Acid

Polysorbate 60

Disodium EDTA

Ethylhexylglycerin

BHT

Sorbitan Isostearate

Vanilla Planifolia Fruit Extract

Dipteryx Odorata Bean Extract

Coumarin

CI 14700

CI 77891

Water, Caprylic/Capric Triglyceride, Glycerin, Isododecane, Cetearyl Olivate, Sodium Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Cetearyl Alcohol, PPG-12/Smdi Copolymer, Sorbitan Olivate, Tocopheryl Acetate, Cyclodextrin, Squalane, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Hydroxyacetophenone, 3-O-Ethyl Ascorbic Acid, Hydroxypropyl Methylcellulose, Sodium Hyaluronate, Phenoxyethanol, Tetrahexyldecyl Ascorbate, Daucus Carota Sativa Seed Oil, Retinal, Rubus Chamaemorus Seed Oil, Alumina, Isostearic Acid, Lecithin, Polyglyceryl-3 Polyricinoleate, Lonicera Japonica Flower Extract, Lonicera Caprifolium Flower Extract, Polyhydroxystearic Acid, Stearic Acid, Sodium Polyaspartate, Pentylene Glycol, Citric Acid, Polysorbate 60, Disodium EDTA, Ethylhexylglycerin, BHT, Sorbitan Isostearate, Vanilla Planifolia Fruit Extract, Dipteryx Odorata Bean Extract, Coumarin, CI 14700, CI 77891

Bifida Ferment Lysate

Methyl Gluceth-20

PEG-75

Bis-PEG-18 Methyl Ether Dimethyl Silane

Butylene Glycol

Propanediol

Cola Acuminata Seed Extract

Hydrolyzed Algin

Pantethine

Caffeine

Tripeptide-32

Sodium Rna

Bisabolol

Glycereth-26

Oleth-3 Phosphate

Caprylyl Glycol

Lactobacillus Ferment

Oleth-3

Oleth-5

Anthemis Nobilis Flower Extract

Faex Extract

Choleth-24

Hydrogenated Lecithin

Ceteth-24

Ethylhexyl Methoxycinnamate

Hexylene Glycol

Carbomer

Triethanolamine

Trisodium EDTA

Xanthan Gum

CI 19140

Water, Bifida Ferment Lysate, Methyl Gluceth-20, PEG-75, Bis-PEG-18 Methyl Ether Dimethyl Silane, Butylene Glycol, Propanediol, Cola Acuminata Seed Extract, Hydrolyzed Algin, Pantethine, Caffeine, Lecithin, Tripeptide-32, Ethylhexylglycerin, Sodium Rna, Bisabolol, Glycereth-26, Squalane, Sodium Hyaluronate, Oleth-3 Phosphate, Caprylyl Glycol, Lactobacillus Ferment, Oleth-3, Oleth-5, Anthemis Nobilis Flower Extract, Faex Extract, Choleth-24, Hydrogenated Lecithin, Ceteth-24, Tocopheryl Acetate, Ethylhexyl Methoxycinnamate, Hexylene Glycol, Carbomer, Triethanolamine, Trisodium EDTA, BHT, Xanthan Gum, Phenoxyethanol, CI 14700, CI 19140

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.

BHT is a synthetic antioxidant and preservative.

As an antioxidant, it helps your body fight off free-radicals. Free-radicals are molecules that may damage your skin cells.

As a preservative, it is used to stabilize products and prevent them from degrading. Specifically, BHT prevents degradation from oxidation.

The concerns related to BHT come from oral studies; this ingredient is currently allowed for use by both the FDA and EU.

However, it was recently restricted for use in the UK as of April 2024.

Ci 14700, also known as Red No. 4, is a synthetic red dye derived from petroleum. It is water soluble.

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.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

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 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.

Squalane is the hydrogenated and shelf-stable form of squalene (a lipid that naturally occurs in human sebum).

It is an emollient and skin conditioning agent that is able to integrate seamlessly into the skin's lipid barrier without clogging pores.

This is due to how structurally similar it is to what your skin already produces.

Though it is mostly an emollient that helps soften and hydrate skin, it also has some humectant and occlusive action. Humectants help the skin retain moisture while occlusives seal it in, making squalane a triple-threat moisturizer.

Research shows it has antioxidant capabilities that help protect against stressors like UV exposure, specifically UVA induced oxidative stress. This study also found that it supports collagen biosynthesis in human dermal fibroblasts.

No clinical study has reported significant adverse effects and irritation reactions are very rare from this ingredient (even at 100% concentration).

Overall, it's a fantastic ingredient for hydration and is suitable for all skin types.

This depends on the source. Squalane can be derived from both plants and animals. Most squalane used in skincare comes from plants.

Please note: the source of squalane is only known if disclosed by the brand. We recommend reaching out to the brand if you have any questions about their squalane.

Read more about squalene with an "e".

Though squalane is often called an oil, it’s technically not one. It is a hydrocarbon, meaning it is only made of carbon and hydrogen. True oils are triglycerides and made of fatty acids and glycerol.

The term “oil-free” isn’t regulated so companies can define it however they want. Some exclude all oils, while others just avoid mineral oil or comedogenic oils.

Squalane has a comedogenic rating of 1 from the original 1972 study that tested raw ingredients under occlusion on rabbit ears. This system is not standardized or peer-reviewed, and using the raw ingredients is very different from how diluted cosmetic formulations are used on human skin.

A comedogenic rating of 1 means it is "unlikely to clog pores" according to the original rating system.

The overall formula of a product matters more than the individual ingredients on whether or not it will cause clogged pores.

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!

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Peptide Therapy Guide Editorial Team

Editorial team for Peptide Therapy Guide.

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