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Paula's Choice Clinical Niacinamide 20% Treatment Versus Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum

Paula's Choice Clinical Niacinamide 20% Treatment Versus Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum This pore-care treatment is formulated around Niacinamide and Acetyl Glucosamine to refine the look of pores and refine skin texture. This oil-contr

Paula's Choice Clinical Niacinamide 20% Treatment Versus Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum

This pore-care treatment is formulated around Niacinamide and Acetyl Glucosamine to refine the look of pores and refine skin texture.

This oil-control serum is formulated around Niacinamide to balance excess oil and refine the look of pores.

What's inside

Key Ingredients

Benefits

Ingredients Side-by-side

Water

Niacinamide 20%

Pentylene Glycol

Butylene Glycol

Glycerin

Acetyl Glucosamine

Ascorbyl Glucoside

Glycyrrhiza Glabra Root Extract

Spiraea Ulmaria Extract

Portulaca Oleracea Extract

Camellia Japonica Flower Extract

Epigallocatechin Gallate

Boerhavia Diffusa Root Extract

Camellia Sinensis Leaf Extract

Allantoin

Lecithin

Pullulan

Panthenol

Silica

Xanthan Gum

Sclerotium Gum

Propanediol

Sodium Phytate

Phenoxyethanol

Ethylhexylglycerin

Water, Niacinamide 20%, Pentylene Glycol, Butylene Glycol, Glycerin, Acetyl Glucosamine, Ascorbyl Glucoside, Glycyrrhiza Glabra Root Extract, Spiraea Ulmaria Extract, Portulaca Oleracea Extract, Camellia Japonica Flower Extract, Epigallocatechin Gallate, Boerhavia Diffusa Root Extract, Camellia Sinensis Leaf Extract, Allantoin, Lecithin, Pullulan, Panthenol, Silica, Xanthan Gum, Sclerotium Gum, Propanediol, Sodium Phytate, Phenoxyethanol, Ethylhexylglycerin

Niacinamide

Methyl Gluceth-20

Hydroxyacetophenone

Sodium Hyaluronate

Caprylyl Glycol

Carbomer

Sodium Hydroxide

Water, Niacinamide, Glycerin, Propanediol, Methyl Gluceth-20, Hydroxyacetophenone, Sodium Hyaluronate, Caprylyl Glycol, Carbomer, Sodium Hydroxide

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.

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.

Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.

And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.

You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.

In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.

If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.

When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.

When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.

In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).

Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.

Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.

The type of niacinamide used in skincare is synthetically created.

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.

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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. 06Ceramide NG is a type of Ceramide. The NG stands for a sphinganine base.
  7. 07Ceramides are intercellular lipids naturally found in our skin that bonds dead skin cells together to create a barrier. They are known for their ability to hold water and thus are a great ingredient for dry skin.
  8. 08Ceramides are an important building block for our skin barrier. A stronger barrier helps the skin look more firm and hydrated. By bolstering the skin ceramides act as a barrier against irritating ingredients. This can help with inflammation as well.
  9. 09If you would like to eat ceramides, sweet potatoes contain a small amount.
  10. 10Read more about other common types of ceramides here: Ceramide AP Ceramide EOP Ceramide NP
  11. 11Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  12. 12Topically, glycerin does several things at once:
  13. 13Your 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.
  14. 14Aquaporin-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.
  15. 15This 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.
  16. 16Just know very high concentrations (>40%) can feel tacky in low humidity.
  17. 17Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  18. 18Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.
  19. 19Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.
  20. 20This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.
Source · skinsort.com
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