Guava Vitamin C Dark Spot Serum
What it's good for
Key actives from our research database. Click any to read the full evidence dossier.
Brightens dull skin and helps fade dark spots. Also defends against everyday UV and pollution damage when worn under sunscreen.
Good for: Brightening, Antioxidant
Fades stubborn dark patches like melasma and deep marks left behind by acne or hormonal shifts. The one to reach for when other brighteners haven't worked.
Good for: Brightening
Boosts the effectiveness of vitamin C and vitamin E when layered together. The reason a good morning antioxidant serum stays potent through the day.
Good for: Antioxidant
A workhorse antioxidant that defends your skin from daily oxidative damage. Pairs especially well with vitamin C, and it's in nearly every good moisturizer for a reason.
Good for: Antioxidant
Evidence behind the ingredients
Real citations from our research database, one per tracked active in this product. Click any ingredient name to read its full evidence dossier.
Brightens dull skin and helps fade dark spots. Also defends against everyday UV and pollution damage when worn under sunscreen.
Krutmann J et al. PINGing Sunshine: A Review of the Evidence for Adding Non-Filtering Photoprotective Ingredients to Sunscreens. Photodermatol Photoimmunol Photomed. 2025;41(6). — Review of Photoprotective INGredients (PINGs); L-ascorbic acid (vitamin C) identified as a top-ranked PING demonstrating efficacy across multiple photodamage endpoints.
Pullar JM et al., The roles of vitamin C in skin health, Nutrients 2017;9(8):866 — concluded topical efficacy "poorly understood"; supports dietary vitamin C
Lee JH et al., Effects of VitabridC12 on Skin Inflammation, Annals of Dermatology 2017
Fades stubborn dark patches like melasma and deep marks left behind by acne or hormonal shifts. The one to reach for when other brighteners haven't worked.
Liang Y et al., Comparative efficacy and safety of tranexamic acid for melasma by different administration methods: A systematic review and network meta-analysis, Journal of Cosmetic Dermatology 2024 — oral TXA + topical agents most effective delivery route
Tranexamic Acid Ameliorates Skin Hyperpigmentation by Downregulating Endothelin-1 Expression in Dermal Microvascular Endothelial Cells, Annals of Dermatology 2024;36(3):151-162 — mechanism study showing oral TXA suppresses endothelin-1 in vascular endothelial cells
Calacattawi R, Alshahrani M, Aleid M et al., Tranexamic acid as a therapeutic option for melasma management: a meta-analysis and systematic review of randomized controlled trials, Journal of Dermatological Treatment 2024;35(1):2361106 — pooled RCT evidence that tranexamic acid significantly reduces melasma severity via plasmin-inhibition of UV-triggered melanogenesis
Boosts the effectiveness of vitamin C and vitamin E when layered together. The reason a good morning antioxidant serum stays potent through the day.
Kim JH et al., Fractional microneedle radiofrequency with the application of vitamin C, E, and ferulic acid serum for neck skin rejuvenation: a prospective, double-blinded, split-neck, placebo-controlled trial, Journal of Dermatological Treatment 2025;36(1):2504655 — CE+ferulic serum + microneedle RF produced superior clinical and histologic neck rejuvenation vs RF alone
Roux M et al., Ferulic Acid Use for Skin Applications: A Systematic Review, Journal of Clinical and Aesthetic Dermatology 2025;18(5):38-42 — SR of 18 human studies; topical ferulic acid improved erythema, pigmentation, hydration, elasticity, texture
Wang X et al., Ferulic Acid in the Treatment of Papulopustular Rosacea: A Randomized Controlled Study, Journal of Cosmetic Dermatology 2025;24(1):e16611 — topical ferulic acid solution twice daily improved papulopustular rosacea
+−1 more ingredient
A workhorse antioxidant that defends your skin from daily oxidative damage. Pairs especially well with vitamin C, and it's in nearly every good moisturizer for a reason.
Neves JR et al., Efficacy of a topical serum containing L-ascorbic acid, neohesperidin, pycnogenol, tocopherol, and hyaluronic acid in relation to skin aging signs, Journal of Cosmetic Dermatology 2022;21(10):4462-4469 — tocopherol-containing antioxidant serum reduced pollution-induced damage and improved aging signs
Warshaw EM et al., Patch Testing With Tocopherol and Tocopherol Acetate: The North American Contact Dermatitis Group Experience, 2001 to 2016, Dermatitis 2021;32(5):308-318 — 15-year NACDG data: positive patch-test reactions to tocopherol rare given widespread cosmetic use
Lin FH et al., Ferulic acid stabilizes a solution of vitamins C and E and doubles its photoprotection of skin, Journal of Investigative Dermatology 2005;125(4):826-832 — ferulic acid + vit C + vit E combo doubled photoprotection vs C+E alone (cross-listed; same paper cited for Ferulic Acid and Vit C)
Sources: 10 clinical journals and regulatory databases across the US, EU, Korea, Japan, and China. Every entry points to a specific document. See methodology for the full list and what each outcome label means.
Full ingredient list
Everything on the package label, not just the tracked actives above.
+−Show all 47 ingredients
Listed in the order printed on the package. By regulation, ingredients at 1% or higher are listed in descending order by concentration, so the first entry is the largest part of the formula.
- Water/Aqua/Eau
- 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 (Apple) Fruit Extract
- Musa Sapientum (Banana) Fruit Extract
- Prunus Armeniaca (Apricot) Kernel Extract
- Pyrus Communis (Pear) Fruit Extract
- Rubus Idaeus (Raspberry) 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
Layering conflicts
Ingredients in this product that can react with common actives. Avoid stacking unless noted.
- Benzoyl Peroxidemedium
Benzoyl peroxide breaks down vitamin C, making both less effective. Use one in the morning and the other at night.
- Retinollow
Vitamin C and retinol work best at different pH levels. Use vitamin C in the morning and retinol at night.
Similar comparisons
Not medical advice. GlowPal is educational. Patch-test new products and talk to a qualified healthcare professional before changing your routine, especially if you're pregnant, nursing, or have a diagnosed skin condition. See our terms.