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Acure Brightening Tranexamic Acid Serum Versus Paula's Choice Discoloration Repair Serum

Acure Brightening Tranexamic Acid Serum Versus Paula's Choice Discoloration Repair Serum 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 Be

Acure Brightening Tranexamic Acid Serum Versus Paula's Choice Discoloration Repair Serum

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

Propanediol

Aloe Barbadensis Leaf Juice

Niacinamide

Tranexamic Acid

Kojic Acid

Carthamus Tinctorius Seed Oil

Zinc PCA

Glycerin

Sclerotium Gum

Xanthan Gum

Sodium Levulinate

Hydroxyethylcellulose

Sodium Phytate

Ethylhexylglycerin

Sodium Anisate

Citric Acid

Water, Propanediol, Aloe Barbadensis Leaf Juice, Niacinamide, Tranexamic Acid, Kojic Acid, Carthamus Tinctorius Seed Oil, Zinc PCA, Glycerin, Sclerotium Gum, Xanthan Gum, Sodium Levulinate, Hydroxyethylcellulose, Sodium Phytate, Ethylhexylglycerin, Sodium Anisate, Citric Acid

C13-15 Alkane

Caprylic/Capric Triglyceride

Dicaprylyl Carbonate

Ethyl Macadamiate

Behenyl Alcohol

Glyceryl Stearate

Butylene Glycol

Silybum Marianum Seed Oil

Tocopherol

Lactobacillus/Coconut Fruit Juice Ferment Filtrate

Lecithin

Bakuchiol

Caprylyl Glycol

Hydrogenated Lecithin

Allantoin

Glycine Soja Oil

Hexylene Glycol

Boerhavia Diffusa Root Extract

Glycine Soja Sterols

Malic Acid

Phenoxyethanol

Water, Niacinamide, Glycerin, Tranexamic Acid, C13-15 Alkane, Caprylic/Capric Triglyceride, Dicaprylyl Carbonate, Ethyl Macadamiate, Behenyl Alcohol, Glyceryl Stearate, Butylene Glycol, Silybum Marianum Seed Oil, Tocopherol, Lactobacillus/Coconut Fruit Juice Ferment Filtrate, Lecithin, Bakuchiol, Xanthan Gum, Caprylyl Glycol, Hydrogenated Lecithin, Allantoin, Glycine Soja Oil, Hexylene Glycol, Boerhavia Diffusa Root Extract, Glycine Soja Sterols, Citric Acid, Sodium Phytate, Malic Acid, Phenoxyethanol, Ethylhexylglycerin

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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.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like 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.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due 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.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most 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.

Rosacea 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.

However, 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 skin is unique, we recommend a patch test if you are unsure.

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.

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 Phytate is the synthetic salt form of phytic acid. Phytic acid is an antioxidant and can be found in plant seeds.

Sodium Phytate is a chelating agent. Chelating agents help prevent metals from binding to water. This helps stabilize the ingredients and the product.

Tranexamic Acid (TXA) is a synthetic lysine derivative that is becoming one of the most exciting brightening ingredients in skincare.

Originally used in medicine as an anti-hemorrhagic agent, its skin brightening potential was discovered by accident; patients taking it orally started noticing their melasma was fading.

Unlike most brighteners that target tyrosinase (the enzyme that synthesizes melanin), TXA works further upstream. It basically blocks your cells from receiving the signal to produce pigment.

This makes it one of the rare actives that works on three pathways at once:

This makes it effective for treating melasma, post-inflammatory hyperpigmentation (PIH), and sun-induced dark spots.

The most effective cosmetic concentration sits between 2-5% and going higher doesn't boost results.

Side effects are generally mild; occasional irritation, flaking, or dryness have been reported at the start of use. Overall, this ingredient is pretty well tolerated, even by sensitive skin types.

Another perk of this ingredient is that it does not cause photosensitivity, so it's safe to use in the AM and PM.

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!

Xanthan gum is used as a stabilizer and thickener within cosmetic products. It helps give products a sticky, thick feeling - preventing them from being too runny.

On the technical side of things, xanthan gum is a polysaccharide - a combination consisting of multiple sugar molecules bonded together.

Xanthan gum is a pretty common and great ingredient. It is a natural, non-toxic, non-irritating ingredient that is also commonly used in food products.

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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. 03Caprylic/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.
  4. 04Though 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.
  5. 05In practice, that translates to a long shelf life and a consistently elegant skin feel.
  6. 06While 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.
  7. 07Fractionated 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.
  8. 08This ingredient is treated as the gold standard fungal acne safe oil. Even though it is coconut derived, the problematic lauric acid is stripped out.
  9. 09This 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…
  10. 10Tocopheryl Acetate is a stable, shelf-friendly form of vitamin E.
  11. 11Formulators love it because plain vitamin E oxidizes quickly once it hits air. This acetate version stays stable and resists going off, helping to extend a product's shelf life.
  12. 12It's actually inactive on its own and works like a slow-release "storage" form; the enzymes in your skin called esterases gradually convert it into active vitamin E over time.
  13. 13One in vivo study showed 5% of the acetate in the living layer of the epidermis converted to vitamin E after 5 days of application. This study also found the skin gained protection against UV damage even though the conversion was slow and small.
  14. 14Once converted, vitamin E acts as a skin's main fat-soluble antioxidant that fights free radicals to protect skin from damage.
  15. 15Topical vitamin E generally boosts the skin's photoprotection, and it reduced UV-damage in animal models.
  16. 16This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.
  17. 17Overall, it has a pretty solid safety profile and has been found to be non-irritating and non-comedogenic. Allergic reactions may happen but stay rare due to how widely the ingredient gets used.
  18. 18The concentration will vary depending on the formula; industry data shows 0.1% in baby lotions, 3% in lipsticks, and 5% in foot powders. You can also find this ingredient at 100% in a pure vitamin E oil.
  19. 19Most leave-on skincare keeps it at the lower end, often between 0.5-1%.
  20. 20Water. 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.
Source · skinsort.com
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Product index

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Comparison edit

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