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Paula's Choice 10% Niacinamide Booster Versus Kiehl's Ultra Pure High-Potency 5.0% Niacinamide Serum

Paula's Choice 10% Niacinamide Booster 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

Paula's Choice 10% Niacinamide Booster 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

Acetyl Glucosamine

Ascorbyl Glucoside

Butylene Glycol

Phospholipids

Sodium Hyaluronate

Allantoin

Boerhavia Diffusa Root Extract

Glycerin

Dipotassium Glycyrrhizate

Glycyrrhiza Glabra Root Extract

Ubiquinone

Epigallocatechin Gallate

Beta-Glucan

Panthenol

Carnosine

Genistein

Citric Acid

Sodium Citrate

Sodium Hydroxide

Xanthan Gum

Disodium EDTA

Ethylhexylglycerin

Phenoxyethanol

Water, Niacinamide, Acetyl Glucosamine, Ascorbyl Glucoside, Butylene Glycol, Phospholipids, Sodium Hyaluronate, Allantoin, Boerhavia Diffusa Root Extract, Glycerin, Dipotassium Glycyrrhizate, Glycyrrhiza Glabra Root Extract, Ubiquinone, Epigallocatechin Gallate, Beta-Glucan, Panthenol, Carnosine, Genistein, Citric Acid, Sodium Citrate, Sodium Hydroxide, Xanthan Gum, Disodium EDTA, Ethylhexylglycerin, Phenoxyethanol

Propanediol

Methyl Gluceth-20

Hydroxyacetophenone

Caprylyl Glycol

Carbomer

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.

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:

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.

Sodium 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.

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!

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The reference edit

Ingredients, questions
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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. 03Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.
  4. 04Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.
  5. 05It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.
  6. 06Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.
  7. 07A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.
  8. 08Ceramide AP is is a skin-identical lipid that mimics what your skin already makes naturally. Ceramides help maintain epidermal integrity and barrier function.
  9. 09You'll often see this ingredient paired with other ceramides (like ceramide NP), cholesterol, or fatty acids because this combination best mimics the natural lipid mix your skin already has.
  10. 10The skin's ability to produce ceramides gets disrupted in skin conditions like eczema. This in turn weakens the skin barrier and applying ceramides topically has been shown to replenish what's been lost to restore barrier function.
  11. 11Most of the studies with Ceramide AP test it as part of a multi-ceramide complex; studies reinforce ceramide AP's role in rebalancing ceramides in skin and improving skin hydration.
  12. 12Ceramide EOP is formally known as Ceramide 1.
  13. 13It is naturally found in skin and part of the intercellular "mortar" holding everything together in your outermost layer.
  14. 14EOP stands for a linked Ester fatty acid, a linked Omega hydroxy fatty acid, and the Phytosphingosine base.
  15. 15What makes Ceramide EOP special is its ultra-long fatty acid chain; this unique structure allows it to bridge the lipid layers in your skin barrier to prevent water loss (something no other ceramide can do).
  16. 16Low levels of Ceramide EOP have been found in people with eczema and psoriasis.
  17. 17Using it together with other ceramides, cholesterol, and linoleic acid have been shown to meaningfully improve hydration and reduce water loss.
  18. 18In one clinical study, a regimen using Ceramide EOP, NP, and AP led to significant symptom improvements in patients with eczema, psoriasis, and dry skin in just 4 weeks.
  19. 19You'll usually see concentrations between 0.1-0.5% in formulations. Overall, this is a well-tolerated and safe ingredient for cosmetic use.
  20. 20Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.
Source · skinsort.com
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