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Anua Azelaic Acid 15+ Intense Calming Serum Versus Isntree Ultra-Low Molecular Hyaluronic Acid Serum

Anua Azelaic Acid 15+ Intense Calming Serum Versus Isntree Ultra-Low Molecular Hyaluronic Acid Serum This calming serum is formulated around Azelaic Acid and Centella Asiatica Extract to calm redness and clear breakouts. This hydrating serum is formulated arou

Anua Azelaic Acid 15+ Intense Calming Serum Versus Isntree Ultra-Low Molecular Hyaluronic Acid Serum

This calming serum is formulated around Azelaic Acid and Centella Asiatica Extract to calm redness and clear breakouts.

This hydrating serum is formulated around Panthenol and Hydrolyzed Hyaluronic Acid to hydrate skin and strengthen the skin barrier.

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

Water

Propylene Glycol

Azelaic Acid

Sodium Hydroxide

1,2-Hexanediol

Centella Asiatica Extract

Dipropylene Glycol

Butylene Glycol

Panthenol

Hydroxyethylcellulose

Glycerin

Ethylhexylglycerin

Melia Azadirachta Leaf Extract

Salicylic Acid

Biosaccharide Gum-1

Allantoin

Dipotassium Glycyrrhizate

Melia Azadirachta Flower Extract

Sodium Hyaluronate

Melaleuca Alternifolia Leaf Oil

Succinic Acid

Totarol

Beta-Glucan

Dextrin

Theobroma Cacao Extract

Centella Asiatica Leaf Extract

Centella Asiatica Root Extract

Madecassoside

Asiaticoside

Asiatic Acid

Madecassic Acid

Tocopherol

Squalane

Zinc PCA

Chlorella Vulgaris Extract

Ceramide NP

Sodium Hyaluronate Dimethylsilanol

Hydrolyzed Hyaluronic Acid

Hydrolyzed Sodium Hyaluronate

Hyaluronic Acid

Potassium Hyaluronate

Hydroxypropyltrimonium Hyaluronate

Sodium Hyaluronate Crosspolymer

Sodium Acetylated Hyaluronate

Water, Propylene Glycol, Azelaic Acid, Sodium Hydroxide, 1,2-Hexanediol, Centella Asiatica Extract, Dipropylene Glycol, Butylene Glycol, Panthenol, Hydroxyethylcellulose, Glycerin, Ethylhexylglycerin, Melia Azadirachta Leaf Extract, Salicylic Acid, Biosaccharide Gum-1, Allantoin, Dipotassium Glycyrrhizate, Melia Azadirachta Flower Extract, Sodium Hyaluronate, Melaleuca Alternifolia Leaf Oil, Succinic Acid, Totarol, Beta-Glucan, Dextrin, Theobroma Cacao Extract, Centella Asiatica Leaf Extract, Centella Asiatica Root Extract, Madecassoside, Asiaticoside, Asiatic Acid, Madecassic Acid, Tocopherol, Squalane, Zinc PCA, Chlorella Vulgaris Extract, Ceramide NP, Sodium Hyaluronate Dimethylsilanol, Hydrolyzed Hyaluronic Acid, Hydrolyzed Sodium Hyaluronate, Hyaluronic Acid, Potassium Hyaluronate, Hydroxypropyltrimonium Hyaluronate, Sodium Hyaluronate Crosspolymer, Sodium Acetylated Hyaluronate

Sea Water

Methylpropanediol

Betaine

Pentylene Glycol

Carbomer

Caprylyl Glycol

Tromethamine

Xanthan Gum

Malachite Extract

Disodium EDTA

Glyceryl Acrylate/Acrylic Acid Copolymer

Glyceryl Glucoside

Dimethylsilanol Hyaluronate

Hydrolyzed Calcium Hyaluronate

Sodium Sulfated Hyaluronate

Sodium Stearoyl Hyaluronate

Sodium Oleoyl Hyaluronate

Sea Water, Water, Methylpropanediol, Glycerin, Butylene Glycol, 1,2-Hexanediol, Betaine, Pentylene Glycol, Carbomer, Caprylyl Glycol, Allantoin, Tromethamine, Ethylhexylglycerin, Xanthan Gum, Panthenol, Malachite Extract, Hydrolyzed Hyaluronic Acid, Disodium EDTA, Glyceryl Acrylate/Acrylic Acid Copolymer, Glyceryl Glucoside, Sodium Hyaluronate, Potassium Hyaluronate, Hyaluronic Acid, Hydrolyzed Sodium Hyaluronate, Sodium Acetylated Hyaluronate, Hydroxypropyltrimonium Hyaluronate, Sodium Hyaluronate Crosspolymer, Dimethylsilanol Hyaluronate, Hydrolyzed Calcium Hyaluronate, Sodium Sulfated Hyaluronate, Madecassoside, Beta-Glucan, Sodium Stearoyl Hyaluronate, Sodium Oleoyl Hyaluronate

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.

1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.

It is a:

Humectant, drawing moisture into the skin

Emollient, helping to soften skin

Solvent, dispersing and stabilizing formulas

Preservative booster, enhancing the antimicrobial activity of other preservatives

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.

Beta-Glucan is a soluble polysaccharide (a chain of glucose sugars) sourced from the cells walls of oats, baker's yeast, mushrooms, and seaweed.

It's a rare ingredient that pulls double-duty as a heavy-duty hydrator and skin-soothing repair agent.

On the surface, it acts as a humectant that holds water in place and reduces moisture loss for a plumper, smoother feel, while its anti-inflammatory and antioxidant properties make it a great pick for calming redness or sensitive skin

The more interesting story is underneath:

Despite its large molecular size, oat beta-glucan has been shown to penetrate the epidermis and reach the dermis by slipping between skin cells. Here, it interacts with fibroblasts and macrophages to nudge collagen synthesis and support wound repair.

A small 2005 split-face clinical study of 27 subjects found topical beta-glucan produced measurable reductions in wrinkle depth, height, and roughness after 8 weeks of use.

It is worth noting the trial was small and the penetration testing used frozen, irradiated skin so the anti-aging data is encouraging rather than definitive.

This ingredient gets along with pretty much everything and is typically used around 0.1-1%.

Fungal acne: This ingredient is not a food source for the Malassezia yeast because it is a glucose polysaccharide with no fatty acid or ester component.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

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.

Hyaluronic acid (HA) is a glycosaminoglycan (basically a long sugar chain) that your skin already makes on its own. In your skin, HA lives in the extracellular matrix and acts as the body's moisture reservoir.

Topically, HA is a humectant that binds water and helps skin look more plump, smooth, and hydrated.

The only catch is that HA isn't a single thing; it actually comes in a wide range of molecular weights (~50 - 2,000+ kDA) and size matters.

Some clinical evidence links low molecular weight versions to improved wrinkle depth, elasticity, anti-inflammatory effects, and barrier repair.

This is why the best HA serums blend the two sizes together so you get the best of both worlds.

The majority of cosmetic HA is produced by bacterial fermentation, typically using Streptococcus or Bacillus strains. Typical use levels in skincare sit around 0.1-2%.

A clinical study using a 0.2% low-molecular weight HA gel showed improvement in facial seborrheic dermatitis with excellent tolerance.

These are some other common types of Hyaluronic Acid:

Hydrolyzed Hyaluronic Acid is hyaluronic acid (HA) that is broken down into lower molecular weight fragments.

It's a humectant that pulls and holds water in the skin to help with hydration, plumpness, and reduce transepidermal water loss.

Because hydrolyzed hyaluronic acid is smaller in size, it can slip past your outermost layer of skin more easily than full-sized HA.

Most formulations will combine all sizes to get the best of both worlds.

Typical usage levels range from 0.01-1%. Any percentage higher than 2% might become goopy and tacky.

This ingredient is created by putting sodium hyaluronate through hydrolysis.

You might know this as 'mini' or 'ultra low-molecular weight' hyaluronic acid. The small molecule size means it is able to travel deeper in the skin.

According to studies, low molecular-weight hyaluronic acid can:

One study from 2011 found ultra-low weight HA to show pro-inflammatory properties. Another study from 2022 found it to downregulate UV-B induced inflammation.

Hydrolysis is a process of changing a molecule using water or enzymes.

This ingredient is water-soluble.

Hydroxypropyltrimonium Hyaluronate is a positively charged version of hyaluronic acid.

This small change does a lot in a formula:

Regular hyaluronic acid carries a negative charge and so does the surface of your skin. This means the two repel each other and hyaluronic acid can be washed away easily. The positive charge here does the opposite: it makes the ingredient cling to your skin (also called "substantivity") so it keeps hydrating even in rinse-off products where it lays down a light, moisture-holding film.

The research backs this up too; a 2025 clinical study on a shower gel containing 0.1% positively charged hyaluronic acid increased skin hydration by 6.6% versus the baseline and 11.1% versus the placebo. This was measured 6 hours after 1 minute of contact and rinse, and on volunteers with very dry skin.

The same team's lab work showed it adhered to skin far better than unmodified hyaluronic acid (+107% vs. low molecular weight, +23% versus high molecular weight). They also found it increased two proteins tied to skin hydration, aquaporin-3 by 16% and filaggrin by 35%.

A separate 2024 study reached a similar conclusion and credited the hydrating benefits to its film-forming properties.

Both studies used the ingredient at 0.1% which also matches how much it usually shows up in products (at fractions of a percent).

One honesty note worth keeping in mind: the published research comes from the company that manufactures the ingredient so independent data would strengthen the picture. However, the results are consistent and the mechanism makes sense.

As a Hyaluronic Acid derivative, it has a well-tolerated profile and suits most skin types.

Madecassoside is one of four active compounds found in Centella asiatica and is one of the main reasons Centella is so effective at calming irritated skin and supporting the moisture barrier.

There's a solid body of peer-reviewed research backing Madecassoside for several skin benefits. Studies have found:

Madecassoside pairs well with other hydrating or antioxidant ingredients like Ascorbic Acid or Hyaluronic Acid.

Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.

There are two forms of panthenol: D and L.

D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.

Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):

Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.

This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.

Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.

This ingredient is also referred to as pro-vitamin B5.

Potassium hyaluronate (PH) is a salt form of hyaluronic acid and has similar skin hydrating benefits.

Similar to hyaluronic acid, PH is able to draw and hold moisture to your skin. This helps keep skin soft and hydrated.

Fun fact: PH is used in eye drops and injectable treatments for joint disorders. It has lubricating and tissue-repair properties.

Sodium Acetylated Hyaluronate is a type of Hyaluronic Acid.

Hyaluronic Acids help moisturize, soothe, and protect the skin.

Read about common types of Hyaluronic Acid here:

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:

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.

Sodium Hyaluronate Crosspolymer is a crosslinked version of sodium hyaluronate. This just means it's linked into a 3D mesh network that lets it be more stable and sit on skin as a cohesive, gel-like film rather than sinking into skin.

A 2016 human skin study found crosslinked HA increased epidermal water content by 7.6% over the control group and reduced transepidermal water loss by 27.8%.

A follow-up clinical trial found that a topical crosslinked HA serum applied after fillers, microneedling, or chemical peels was well-tolerated and enhanced skin quality at 14 / 28 days.

More recent research suggests that concentrations as low as 0.03% can act as a penetration enhancer for other skincare actives.

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 Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.
  4. 04Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.
  5. 05Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).
  6. 06Chlorphenesin is a synthetic preservative. It helps protect a product against bacteria in order to extend shelf life. In most cases, Chlorphenesin is paired with other preservatives such as phenoxyethanol and caprylyl glycol.
  7. 07Chlorphenesin is a biocide. This means it is able to help fight the microorganisms on our skin. It is also able to fight odor-releasing bacteria.
  8. 08Chlorphenesin is soluble in both water and glycerin.
  9. 09Studies show Chlorphenesin is easily absorbed by our skin. You should speak with a skincare professional if you have concerns about using Chlorphenesin.
  10. 10Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  11. 11Like 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.
  12. 12However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  13. 13Due 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.
  14. 14In skincare formulas, citric acid can:
  15. 15While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  16. 16Most 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.
  17. 17Rosacea 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.
  18. 18However, 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…
  19. 19Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  20. 20The 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 …
Source · skinsort.com
02

Product index

Related product references

Product

Cera di Cupra Hyaluronic Acid Serum

Cera di Cupra Hyaluronic Acid Serum Ingredients in Cera di Cupra Hyaluronic Acid Serum explained: benefits, concerns, and detailed analysis of 11 ingredients including Water, Glycerin, and …

Source: skinsort.comView reference →
03

Comparison edit

Read side by side

04

Ask the journal

Related questions

01How to Apply Face Serums

Skincare rules can get confusing, but when it comes to application the general rule of thumb is to pay attention to the product’s consistency. “Apply the lightest, thinnest product first and the heaviest, and more dense products last, since thinner products can’t penetrate thicker products,”says Dr. Lewis. After cleansing the face and following up with a toner, let the skin dry before using a serum. You can layer different serums on top of each other or opt for a product that has a precise mix of multiple hero ingredients, such as hyaluronic acid and vitamin C.

Source · www.skincare.com
02What Skin Types Should Use Hyaluronic Acid?

“Hyaluronic acid is particularly helpful for those experiencing dry skin, and for those desiring a plumping effect,” explains Dr. King. But, if you have an oily skin type, don’t discredit hyaluronic acid from your routine just yet. Despite the excess sebum that you may experience, it’s important to keep your skin hydrated so that it doesn’t overcompensate and produce even more oil as a result. Besides your skin type, you should also look at the condition of your skin to decide if it’s time to begin using hyaluronic acid. “If your skin is starting to look dull, flaky and you’re seeing more pronounced fine lines and wrinkles, that’s a pretty good indication that it’s time to add this ingredient to your routine,” adds O’Conner.

Source · www.skincare.com