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Allies of Skin Retinal & Peptides Repair Night Cream Versus Sunday Riley A+ High-Dose Retinol Serum

Allies of Skin Retinal & Peptides Repair Night Cream Versus Sunday Riley A+ High-Dose Retinol Serum This anti-aging night moisturizer is formulated around Palmitoyl Tetrapeptide-7 and Niacinamide to soften the look of wrinkles and strengthen the skin barrier.

Allies of Skin Retinal & Peptides Repair Night Cream Versus Sunday Riley A+ High-Dose Retinol Serum

This anti-aging night moisturizer is formulated around Palmitoyl Tetrapeptide-7 and Niacinamide to soften the look of wrinkles and strengthen the skin barrier.

This anti-aging serum is formulated around Hydroxypinacolone Retinoate and Retinol to soften the look of wrinkles and refine skin texture.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Caprylic/Capric Triglyceride

Propanediol

Argania Spinosa Kernel Oil

Sodium Acrylates Copolymer

Hydrolyzed Candida Saitoana Extract

Sodium Stearoyl Glutamate

Albizia Julibrissin Bark Extract

Dimethyl Isosorbide

Galactoarabinan

Palmitoyl Tetrapeptide-7

Palmitoyl Oligopeptide

Caprooyl Tetrapeptide-3

Cassia Angustifolia Seed Polysaccharide

Hyaluronic Acid

Oxycoccus Palustris Seed Oil

Rubus Chamaemorus Seed Oil

Niacinamide

Withania Somnifera Root Extract

Citrus Aurantium Dulcis Callus Culture Extract

Retinal

Ellagic Acid

Phenyl T-Butylnitrone

Ergothioneine

Glutathione

Mirabilis Jalapa Flower/Leaf/Stem Extract

N-Hydroxysuccinimide

Chrysin

Glutamylamidoethyl Imidazole

Lonicera Caprifolium Flower Extract

Lonicera Japonica Flower Extract

Lavandula Hybrida Oil

Pentylene Glycol

Butylene Glycol

Cyclodextrin

Caprylyl Glycol

Steareth-20

Citric Acid

Xanthan Gum

Dextran

Acetyl Tributyl Citrate

Potassium Sorbate

Phenoxyethanol

Geraniol

Limonene

Linalool

Water, Glycerin, Caprylic/Capric Triglyceride, Propanediol, Argania Spinosa Kernel Oil, Sodium Acrylates Copolymer, Hydrolyzed Candida Saitoana Extract, Sodium Stearoyl Glutamate, Albizia Julibrissin Bark Extract, Dimethyl Isosorbide, Galactoarabinan, Palmitoyl Tetrapeptide-7, Palmitoyl Oligopeptide, Caprooyl Tetrapeptide-3, Cassia Angustifolia Seed Polysaccharide, Hyaluronic Acid, Oxycoccus Palustris Seed Oil, Rubus Chamaemorus Seed Oil, Niacinamide, Withania Somnifera Root Extract, Citrus Aurantium Dulcis Callus Culture Extract, Retinal, Ellagic Acid, Phenyl T-Butylnitrone, Ergothioneine, Glutathione, Mirabilis Jalapa Flower/Leaf/Stem Extract, N-Hydroxysuccinimide, Chrysin, Glutamylamidoethyl Imidazole, Lonicera Caprifolium Flower Extract, Lonicera Japonica Flower Extract, Lavandula Hybrida Oil, Pentylene Glycol, Butylene Glycol, Cyclodextrin, Caprylyl Glycol, Steareth-20, Citric Acid, Xanthan Gum, Dextran, Acetyl Tributyl Citrate, Potassium Sorbate, Phenoxyethanol, Geraniol, Limonene, Linalool

Triheptanoin

Dimethicone

Hexyldecanol

Disiloxane

Cetyl PEG/PPG-10/1 Dimethicone

Diheptyl Succinate

Propylene Carbonate

Hydroxypinacolone Retinoate

PPG-24-Glycereth-24

Phenyl Trimethicone

Retinol

Ubiquinone

Honey Extract

Sodium Hyaluronate Crosspolymer

Algae Extract

Zingiber Officinale Extract

Opuntia Ficus-Indica Fruit Extract

Bisabolol

Butyrospermum Parkii Butter

Phospholipids

Saccharomyces Cerevisiae Extract

Lecithin

Hydrogenated Polyisobutene

1,2-Hexanediol

4-T-Butylcyclohexanol

Polyglyceryl-10 Stearate

Helianthus Annuus Seed Oil

Sorbitol

Cetylhydroxyproline Palmitamide

Polysilicone-11

Benzoic Acid

Dehydroacetic Acid

Sodium Phytate

Glyceryl Polyacrylate

Polysorbate 80

Hydroxyphenyl Propamidobenzoic Acid

Stearic Acid

Brassica Campestris Sterols

Pvp

Capryloyl Glycerin/Sebacic Acid Copolymer

Sodium Benzoate

Alcohol

Potassium Phosphate

Decyl Glucoside

Hexylene Glycol

Tocopherol

Water, Propanediol, Dimethyl Isosorbide, Triheptanoin, Dimethicone, Glycerin, Pentylene Glycol, Hexyldecanol, Disiloxane, Cetyl PEG/PPG-10/1 Dimethicone, Diheptyl Succinate, Propylene Carbonate, Hydroxypinacolone Retinoate, PPG-24-Glycereth-24, Phenyl Trimethicone, Retinol, Ubiquinone, Honey Extract, Sodium Hyaluronate Crosspolymer, Algae Extract, Zingiber Officinale Extract, Opuntia Ficus-Indica Fruit Extract, Bisabolol, Butyrospermum Parkii Butter, Phospholipids, Saccharomyces Cerevisiae Extract, Lecithin, Sodium Acrylates Copolymer, Hydrogenated Polyisobutene, 1,2-Hexanediol, 4-T-Butylcyclohexanol, Polyglyceryl-10 Stearate, Caprylyl Glycol, Helianthus Annuus Seed Oil, Sorbitol, Cetylhydroxyproline Palmitamide, Polysilicone-11, Benzoic Acid, Dehydroacetic Acid, Sodium Phytate, Glyceryl Polyacrylate, Polysorbate 80, Hydroxyphenyl Propamidobenzoic Acid, Stearic Acid, Brassica Campestris Sterols, Pvp, Capryloyl Glycerin/Sebacic Acid Copolymer, Sodium Benzoate, Alcohol, Potassium Phosphate, Decyl Glucoside, Phenoxyethanol, Hexylene Glycol, Potassium Sorbate, Tocopherol

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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.

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).

Dimethyl Isosorbide (often shortened to DMI) is a sugar-derived solvent made from sorbitol. It's used to dissolve tricky ingredients and help them mix smoothly into a formula.

Many actives sit as gritty crystals when undissolved, so DMI swoops in to full dissolve them. This helps improve texture, stability, and how evenly an active is distributed.

It does have a penetration-enhancing reputation that is a bit more nuanced than marketing suggests; a cell study on human skin found that 10% DMI didn't significantly boost the permeation of Hydroquinone, Salicylic Acid, or Octadecenedioic Acid compared to controls (though it did improve their solubility in the formula itself).

Typical usage concentrations usually range from 1-10% depending on the formula's needs; this ingredient is also well tolerated at these levels.

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.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

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.

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.

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.

This ingredient is a synthetic, salt form polymer built from acrylic acid, ethacrylic acid, or their simple esters. It works as a binder, film former, and viscosity increasing agent.

Typical concentrations start at around 0.5% but can go up to 25% for film-forming or binding.

The CIR Expert Panel assessed the safety of 126 acrylates copolymers and concluded they are safe in cosmetics at current use levels when formulated to be non-irritating. They also noted the levels present in finished cosmetic products are not considered a safety risk and Genotoxicity testing (Ames tests, chromosomal aberration assays) has come back negative across the board.

Though the raw building blocks (like acrylic acid) can be irritating on their own, cosmetic-grade versions go through purification to keep levels extremely low.

Sodium Acrylates Copolymer is a large molecule that doesn't penetrate skin barrier in any meaningful way.

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
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Formula cabinet

Ingredients & structured notes

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Product index

Related product references

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Comparison edit

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