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Paula's Choice Discoloration Repair Serum Versus Glow Recipe Guava Vitamin C Dark Spot Treatment Serum

Paula's Choice Discoloration Repair Serum Versus Glow Recipe Guava Vitamin C Dark Spot Treatment Serum This brightening serum is formulated around Niacinamide and Tranexamic Acid to fade the look of dark spots and brighten dull-looking skin. This brightening s

Paula's Choice Discoloration Repair Serum Versus Glow Recipe Guava Vitamin C Dark Spot Treatment Serum

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

This brightening serum is formulated around Tetrahexyldecyl Ascorbate 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

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

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

Propanediol

C9-12 Alkane

Psidium Guajava Fruit Extract

Tetrahexyldecyl Ascorbate

Sodium Polyacryloyldimethyl Taurate

3-O-Ethyl Ascorbic Acid

Ascorbyl Glucoside

Magnesium Ascorbyl Phosphate

Sodium Ascorbyl Phosphate

Psidium Guajava Seed Oil

Tocopheryl Acetate

Sodium Hyaluronate

Ferulic Acid

Tremella Fuciformis Sporocarp Extract

Pyrus Malus Fruit Extract

Musa Sapientum Fruit Extract

Prunus Armeniaca Kernel Extract

Pyrus Communis Fruit Extract

Rubus Idaeus Fruit Extract

Melia Azadirachta Flower Extract

Melia Azadirachta Leaf Extract

Corallina Officinalis Extract

Coccinia Indica Fruit Extract

Hexanoyl Dipeptide-3 Norleucine Acetate

Polyglyceryl-10 Dioleate

1,2-Hexanediol

Hydroxyacetophenone

Sodium Stearoyl Glutamate

Coco-Caprylate/Caprate

Betaine

Polyglyceryl-10 Dipalmitate

Sodium Citrate

Potassium Sorbate

Decyl Glucoside

Lauryl Glucoside

Water, Propanediol, C9-12 Alkane, Psidium Guajava Fruit Extract, Tetrahexyldecyl Ascorbate, Tranexamic Acid, Sodium Polyacryloyldimethyl Taurate, 3-O-Ethyl Ascorbic Acid, Ascorbyl Glucoside, Magnesium Ascorbyl Phosphate, Sodium Ascorbyl Phosphate, Psidium Guajava Seed Oil, Tocopherol, Tocopheryl Acetate, Sodium Hyaluronate, Ferulic Acid, Tremella Fuciformis Sporocarp Extract, Pyrus Malus Fruit Extract, Musa Sapientum Fruit Extract, Prunus Armeniaca Kernel Extract, Pyrus Communis Fruit Extract, Rubus Idaeus Fruit Extract, Melia Azadirachta Flower Extract, Melia Azadirachta Leaf Extract, Corallina Officinalis Extract, Coccinia Indica Fruit Extract, Hexanoyl Dipeptide-3 Norleucine Acetate, Polyglyceryl-10 Dioleate, Glycerin, 1,2-Hexanediol, Caprylic/Capric Triglyceride, Caprylyl Glycol, Hydroxyacetophenone, Sodium Stearoyl Glutamate, Coco-Caprylate/Caprate, Betaine, Lecithin, Polyglyceryl-10 Dipalmitate, Sodium Citrate, Sodium Phytate, Potassium Sorbate, Decyl Glucoside, Lauryl Glucoside, Ethylhexylglycerin, Citric Acid, Xanthan Gum, 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.

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%.

Caprylyl Glycol is a humectant, skin conditioner, emollient, and preservative booster derived from either caprylic acid or synthetically created.

Typical use levels vary from 0.3-1% as a preservative booster and go up to 2% to condition skin.

Because it is not a free-fatty acid, this ingredient is fungal acne safe (there's nothing for Malassezia to feed on).

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.

Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.

Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:

It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.

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.

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.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This 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.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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.

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 Side-by-side

  1. 01Water
  2. 02Ethyl Macadamiate
  3. 03Glycerin
  4. 04Cetearyl Alcohol
  5. 05Propanediol
  6. 06Triethylhexanoin
  7. 07Sodium Acrylates Copolymer
  8. 08Glyceryl Stearate
  9. 09PEG-100 Stearate
  10. 10Glycyrrhiza Glabra Root
  11. 11Hydrolyzed Pumpkin Seedcake
  12. 12Vaccinium Angustifolium Fruit Extract
  13. 13Euterpe Oleracea Fruit Extract
  14. 14Prunus Serotina Fruit Extract
  15. 15Niacinamide
  16. 16Tripeptide-29
  17. 17Ceramide NP
  18. 18Ceramide AP
  19. 19Ceramide EOP
  20. 20Sodium Hyaluronate
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side