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Skin Republic Niacinamide 10% + Zinc 1% Serum Versus Paula's Choice 10% Niacinamide Booster

Skin Republic Niacinamide 10% + Zinc 1% Serum Versus Paula's Choice 10% Niacinamide Booster This oil-control serum is formulated around Niacinamide and Zinc PCA to balance excess oil and refine the look of pores. This pore-care treatment is formulated around N

Skin Republic Niacinamide 10% + Zinc 1% Serum Versus Paula's Choice 10% Niacinamide Booster

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

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

What's inside

Key Ingredients

Benefits

Concerns

No concerns

Ingredients Side-by-side

Water

Niacinamide

Propylene Glycol

Zinc PCA

Glyoxal

Hydroxyethylcellulose

PPG-1-PEG-9 Lauryl Glycol Ether

Phenoxyethanol

Water, Niacinamide, Propylene Glycol, Zinc PCA, Glyoxal, Hydroxyethylcellulose, PPG-1-PEG-9 Lauryl Glycol Ether, Phenoxyethanol

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

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

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.

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.

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.

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. 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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