Avène Hydrance Boost Concentrated Hydrating Serum Versus REN Clean Skincare EVERCALM Redness Relief Serum
This hydrating serum is formulated around Niacinamide and Sodium Hyaluronate to hydrate skin and strengthen the skin barrier.
This calming serum is formulated around Albatrellus Confluens Extract and Laminaria Ochroleuca Extract to calm redness.
What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Skin ConditioningCaprylic/Capric Triglyceride
Masking
Glycerin
Humectant
Propanediol
Solvent
Coco-Caprylate/Caprate
Emollient
Squalane
Emollient
Cetyl Alcohol
Emollient
Cetyl Phosphate
EmulsifyingCrambe Abyssinica Seed Oil
Skin Conditioning
Arginine
Masking
Glycine Soja Oil
Emollient
Glyceryl Stearate
Emollient
Phenoxyethanol
Preservative
Sodium Dehydroacetate
Preservative
Ethylhexylglycerin
Skin ConditioningInulin
Skin Conditioning
Vaccinium Vitis-Idaea Seed Oil
Antioxidant
Sclerotium Gum
Emulsion StabilisingTocopherol
Antioxidant
Sodium Hyaluronate
Humectant
Albatrellus Confluens Extract
Humectant
Alpha-Glucan Oligosaccharide
Cleansing
Xanthan Gum
EmulsifyingSodium Carboxymethyl Betaglucan
Biosaccharide Gum-4
Skin Conditioning
Laminaria Ochroleuca Extract
Skin Conditioning
Citrus Aurantium Amara Flower Extract
RefreshingBeta-Carotene
Skin ConditioningXanthophylls
Skin ConditioningHelianthus Annuus Seed Oil
Emollient
Rosmarinus Officinalis Leaf Extract
AntimicrobialCitric Acid
Buffering
Lactic Acid
Buffering
Sodium Hydroxide
BufferingGeraniol
Perfuming
Linalool
Perfuming
Water, Caprylic/Capric Triglyceride, Glycerin, Propanediol, Coco-Caprylate/Caprate, Squalane, Cetyl Alcohol, Cetyl Phosphate, Crambe Abyssinica Seed Oil, Arginine, Glycine Soja Oil, Glyceryl Stearate, Phenoxyethanol, Sodium Dehydroacetate, Ethylhexylglycerin, Inulin, Vaccinium Vitis-Idaea Seed Oil, Sclerotium Gum, Tocopherol, Sodium Hyaluronate, Albatrellus Confluens Extract, Alpha-Glucan Oligosaccharide, Xanthan Gum, Sodium Carboxymethyl Betaglucan, Biosaccharide Gum-4, Laminaria Ochroleuca Extract, Citrus Aurantium Amara Flower Extract, Beta-Carotene, Xanthophylls, Helianthus Annuus Seed Oil, Rosmarinus Officinalis Leaf Extract, Citric Acid, Lactic Acid, Sodium Hydroxide, Geraniol, Linalool
Reviews
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
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.
Learn more about Citric AcidGlycerin (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.
Learn more about GlycerinPropanediol 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.
Learn more about PropanediolSclerotium Gum is a natural sugar-based fiber made by fermenting a fungus called Sclerotium rolfsii. It's often used as the plant-friendly alternative for synthetic thickeners like carbomer.
In skincare, it works as a thickener, gel former, and stabilizer that keeps heavy ingredients suspended so a product does not separate.
It is non-ionic and forms a triple helix in solution. This is just a fancy way of saying it builds a smooth, cushiony, and non-sticky gel that feels silkier than many other gums.
Another perk of this ingredient is that it is very sturdy and holds up across a wide pH range (~2-11). It's also good at resisting heat and hydrolysis.
Since it holds water at the skin surface, it can provide some light hydration as well.
Typical use levels are around 0.25-2%; formulators usually use 0.2-0.5% to thicken lotions and up to 2% for a firmer gel base.
This ingredient has been found safe in cosmetics with no meaningful evidence of skin sensitization.
Learn more about Sclerotium GumSodium 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.
Learn more about Sodium HyaluronateSodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.
In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.
Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.
"Alkaline" refers to a high pH level. A low pH level would be considered acidic.
Learn more about Sodium HydroxideWater. 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!
Learn more about Water
