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Niod Copper Amino Isolate Serum 3 1:1 (CAIS3) Versus SkinMedica TNS® Advanced+ Serum

Niod Copper Amino Isolate Serum 3 1:1 (CAIS3) Versus SkinMedica TNS® Advanced+ Serum This anti-aging serum is formulated around Tripeptide-29 and Tripeptide-1 to soften the look of wrinkles. What's inside Key Ingredients Benefits Concerns Ingredients Side-by-s

Niod Copper Amino Isolate Serum 3 1:1 (CAIS3) Versus SkinMedica TNS® Advanced+ Serum

This anti-aging serum is formulated around Tripeptide-29 and Tripeptide-1 to soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Tripeptide-29

Bis(Tripeptide-1) Copper Acetate

Tripeptide-1

Myristoyl Nonapeptide-3

Trifluoroacetyl Tripeptide-2

Acetyl Tetrapeptide-2

Sodium Hyaluronate Crosspolymer

Glycogen

Propanediol

Pentylene Glycol

Dextran

Dimethyl Isosorbide

Ethoxydiglycol

Isoceteth-20

Leuconostoc/Radish Root Ferment Filtrate

Caprylyl Glycol

Ethylhexylglycerin

Phenoxyethanol

Chlorphenesin

Water, Glycerin, Tripeptide-29, Bis(Tripeptide-1) Copper Acetate, Tripeptide-1, Myristoyl Nonapeptide-3, Trifluoroacetyl Tripeptide-2, Acetyl Tetrapeptide-2, Sodium Hyaluronate Crosspolymer, Glycogen, Propanediol, Pentylene Glycol, Dextran, Dimethyl Isosorbide, Ethoxydiglycol, Isoceteth-20, Leuconostoc/Radish Root Ferment Filtrate, Caprylyl Glycol, Ethylhexylglycerin, Phenoxyethanol, Chlorphenesin

Human Neonatal Fibroblast Conditioned Media

Glycereth-7 Triacetate

Shea Butter Ethyl Esters

Lactococcus Ferment Lysate

Whey Protein

Chlorella Vulgaris Extract

Saccharide Isomerate

Dimer Tripeptide-43

Vitis Vinifera Flower Cell Extract

Pyrus Malus Fruit Extract

Hydroxyacetophenone

Tocopheryl Acetate

Xanthan Gum

Polyacrylate Crosspolymer-6

Polyacrylate-13

Polyisobutene

Sclerotium Gum

PEG-12 Dimethicone

Lecithin

Pullulan

Butylene Glycol

Sodium Citrate

Polysorbate 20

Aminomethyl Propanol

Disodium EDTA

Water, Pentylene Glycol, Human Neonatal Fibroblast Conditioned Media, Glycereth-7 Triacetate, Shea Butter Ethyl Esters, Glycerin, Ethoxydiglycol, Lactococcus Ferment Lysate, Whey Protein, Chlorella Vulgaris Extract, Saccharide Isomerate, Dimer Tripeptide-43, Vitis Vinifera Flower Cell Extract, Pyrus Malus Fruit Extract, Hydroxyacetophenone, Tocopheryl Acetate, Propanediol, Xanthan Gum, Polyacrylate Crosspolymer-6, Polyacrylate-13, Polyisobutene, Sclerotium Gum, PEG-12 Dimethicone, Lecithin, Pullulan, Butylene Glycol, Sodium Citrate, Polysorbate 20, Aminomethyl Propanol, Disodium EDTA, Phenoxyethanol, Ethylhexylglycerin

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.

Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.

In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling

This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.

It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.

The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it interacting gently with the lipids and water in your outermost layer of skin.

Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).

Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.

Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.

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.

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.

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.

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. 03Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.
  4. 04Like 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.
  5. 05However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.
  6. 06Due 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.
  7. 07In skincare formulas, citric acid can:
  8. 08While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.
  9. 09Most 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.
  10. 10Rosacea 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.
  11. 11However, 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…
  12. 12Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  13. 13Topically, glycerin does several things at once:
  14. 14Your 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.
  15. 15Aquaporin-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.
  16. 16This 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.
  17. 17Just know very high concentrations (>40%) can feel tacky in low humidity.
  18. 18Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  19. 19Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).
  20. 20It 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.
Source · skinsort.com
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Product index

Related product references

03

Comparison edit

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