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Paula's Choice Resist Triple Active Total Repair Serum Versus Numbuzin No.5 Vitamin Concentrated Serum

Paula's Choice Resist Triple Active Total Repair Serum Versus Numbuzin No.5 Vitamin Concentrated Serum This anti-aging serum is formulated around Niacinamide and Retinyl Propionate to soften the look of wrinkles and fade the look of dark spots. This brightenin

Paula's Choice Resist Triple Active Total Repair Serum Versus Numbuzin No.5 Vitamin Concentrated Serum

This anti-aging serum is formulated around Niacinamide and Retinyl Propionate to soften the look of wrinkles and fade the look of dark spots.

This brightening serum is formulated around Niacinamide and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Isopropyl Myristate

Caprylic/Capric Triglyceride

Glycerin

Niacinamide

Hydroxystearic Acid

Oryza Sativa Bran Oil

Tocotrienols

Retinyl Propionate

Hexylresorcinol

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Cetyl Alcohol

Castanea Sativa Leaf Extract

Hydroxyacetophenone

Ceramide AP

1,2-Hexanediol

Caprylyl Glycol

Sodium Hydroxide

Dilauryl Thiodipropionate

Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate

Sodium Phytate

BHT

Water, Isopropyl Myristate, Caprylic/Capric Triglyceride, Glycerin, Niacinamide, Hydroxystearic Acid, Oryza Sativa Bran Oil, Tocotrienols, Retinyl Propionate, Hexylresorcinol, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Cetyl Alcohol, Castanea Sativa Leaf Extract, Hydroxyacetophenone, Ceramide AP, 1,2-Hexanediol, Caprylyl Glycol, Sodium Hydroxide, Dilauryl Thiodipropionate, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, Sodium Phytate, BHT

Vaccinium Vitis-Idaea Fruit Extract

Butylene Glycol

Panthenol

Tranexamic Acid

Neopentyl Glycol Dicaprate

Sorbitol

Bifida Ferment Lysate

Chondrus Crispus Extract

Butyrospermum Parkii Butter

Saccharum Officinarum Extract

Alpha-Arbutin

Sodium Hyaluronate

Melia Azadirachta Flower Extract

Ocimum Sanctum Leaf Extract

Melia Azadirachta Leaf Extract

Curcuma Longa Root Extract

Corallina Officinalis Extract

Tremella Fuciformis Extract

Pentylene Glycol

3-O-Ethyl Ascorbic Acid

Bisabolol

Tromethamine

Ethylhexylglycerin

Adenosine

Hydrogenated Lecithin

Allantoin

Glutathione

Ceramide NP

Beta-Glucan

Dipotassium Glycyrrhizate

Tocopherol

Ascorbic Acid

Ascorbyl Glucoside

Tocopheryl Acetate

Hydroxypropyl Cyclodextrin

Ubiquinone

Thioctic Acid

Potassium Hydroxide

Behenyl Alcohol

Carbomer

Xanthan Gum

Disodium EDTA

Vaccinium Vitis-Idaea Fruit Extract, Butylene Glycol, Niacinamide, Panthenol, Tranexamic Acid, Water, 1,2-Hexanediol, Neopentyl Glycol Dicaprate, Caprylic/Capric Triglyceride, Sorbitol, Bifida Ferment Lysate, Chondrus Crispus Extract, Butyrospermum Parkii Butter, Saccharum Officinarum Extract, Alpha-Arbutin, Sodium Hyaluronate, Melia Azadirachta Flower Extract, Ocimum Sanctum Leaf Extract, Melia Azadirachta Leaf Extract, Curcuma Longa Root Extract, Corallina Officinalis Extract, Tremella Fuciformis Extract, Pentylene Glycol, Glycerin, 3-O-Ethyl Ascorbic Acid, Bisabolol, Tromethamine, Ethylhexylglycerin, Adenosine, Hydrogenated Lecithin, Allantoin, Glutathione, Ceramide NP, Beta-Glucan, Dipotassium Glycyrrhizate, Tocopherol, Ascorbic Acid, Ascorbyl Glucoside, Tocopheryl Acetate, Hydroxypropyl Cyclodextrin, Ubiquinone, Thioctic Acid, Potassium Hydroxide, Behenyl Alcohol, Carbomer, Xanthan Gum, Disodium EDTA

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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

Caprylic/Capric Triglyceride (aka MCT Oil) is a lightweight emollient, solvent, and texture enhancer. It is considered a skin-softener by helping to prevent moisture loss.

Though it behaves like an oil, it is not technically one due to its chemical composition. One perk of this ingredient is that it is very stable, resistant to oxidation, and unlikely to go rancid.

In practice, that translates to a long shelf life and a consistently elegant skin feel.

While there is an assumption Caprylic Triglyceride can clog pores due to it being derived from coconut oil, there is no research supporting this. Just patch test if you have concerns.

Fractionated coconut oil and MCT Oil are both listed as Caprylic/Capric Triglyceride according to INCI. This is because INCI names are based on the ingredient’s final chemical composition and not its marketing name or source.

This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.

This leaves just caprylic (C8) and capric (C10) acid. These chain lengths actually trend antifungal; a 2020 study found caprylic acid was enough to disrupt Malassezia furfur cell membrane, with a caprylic acid derivative damaging membrane structures at concentrations as low as 0.2%.

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.

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. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.
  6. 06A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.
  7. 07Aloe Barbadensis Leaf Juice is the filtered, stabilized liquid pressed from the inner gel of the aloe vera leaf.
  8. 08In cosmetics, it shows up as either soothing active or a water-replacement base. It is roughly 98-99% water and the last 1-2% is an interesting mix of polysaccharides, amino acids, vitamins, minerals, and enzymes.
  9. 09The polysaccharides do most of the work: they bind water at the skin surface for a light, non-greasy hydration boost. And one of the polysaccharides, glycomannan, is linked to fibroblast stimulation + collagen synthesis. This is also why aloe has su…
  10. 10This ingredient is also calming with anti-inflammatory and mild antimicrobial activity, making it a great pick for sensitive, irritated, or post-sun skin.
  11. 11Realistic expectations matter though; the solid evidence is mostly limited to hydration, soothing, and wound support. Deeper claims about anti-aging or sun protection are not well backed, and science reviews note it does not prevent radiation-induce…
  12. 12Because it plays well with almost everything, it's commonly used as a base alongside other actives like niacinamide or vitamin C.
  13. 13Typical usage concentrations range from 0.5% (where hydration benefits already show up) all the way to 90%+ (where it replaces water as the main base).
  14. 14The safety for this ingredient is well-establish as well. Overall, this is a great supporting ingredient for those who want a boost in hydration.
  15. 15Also known as Avobenzone, this ingredient is an oil-soluble used to absorb the full spectrum of UVA rays (peak 357 nm).
  16. 16It's one of the most effective UVA filters available but has a major caveat of photostability: avobenzone is susceptible to photodegradation.
  17. 17This means it can lose efficacy when exposed to sunlight without the help of a stabilizing agent.
  18. 18Studies show antioxidants (like vitamin E or vitamin C) and some UV filters (like octocrylene and Tinosorb S) can meaningfully improve its stability in a formulation.
  19. 19The maximum allowable concentration according to regulation is 3% in the US + Canada, and 5% in the EU, Australia, China, Korea, and ASEAN countries.
  20. 20It has a well-support safety profile: a comprehensive 2025 review found minimal toxicity with no evidence of carcinogenicity.
Source · skinsort.com
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Product index

Related product references

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Comparison edit

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