SKINFOOD Yuja C Dark Spot Clear Serum for acne-prone skin

How to apply

Questions and answers

What the research says

• Niacinamide significantly decreased hyperpigmentation and increased skin lightness compared with vehicle alone after 4 weeks of use in women by inhibiting melanosome transfer.

  The British Journal of Dermatology, 2002

• Topical combination of 5% sodium ascorbyl phosphate and 0.2% retinol reduced inflammatory acne lesions by 29.28% at 4 weeks and 63.10% at 8 weeks, outperforming either agent alone.

  International Journal of Cosmetic Science, 2009

• A single application of a moisturizing fluid containing hyaluronic acid 1%, glycerin 5%, and Centella asiatica stem cells extract significantly increased skin hydration by 29% and reduced transepidermal water loss at 24 hours compared to baseline and an untreated control site in twenty healthy women.

  Clinical, Cosmetic and Investigational Dermatology, 2017

• Topical treatment of nicotinamide, alone or in combination with other active ingredients, reduces the progression of skin aging and hyperpigmentation in clinical trials while being well tolerated.

  Antioxidants, 2021

• Citrus junos callus extract decreased melanin content in melanocytes 1.85-fold compared with arbutin and promoted the proliferation of and procollagen synthesis by human fibroblasts by 154% and 176% at 500 μg/mL.

  Molecules, 2017

• Yuja-peel fractions (ethyl acetate, hexane, and butanol) inhibited MMP expression, induced moisturizing factors filaggrin and serine palmitoyltransferase, and decreased melanin content in UVB-irradiated HaCaT, HDF, and α-MSH-treated B16F10 cells.

  Antioxidants, 2022

• Upcycled low-molecular-weight anionic peptides from Citrus junos seeds protected UVR-irradiated keratinocytes and reconstructed skin tissue by scavenging reactive oxygen species, reducing paracrine cytokines, inhibiting melanin synthesis and TRP-2 expression, and increasing filaggrin, laminin-5, and type I collagen expression.

  International Journal of Molecular Sciences, 2024

• Topical application of 5% vitamin C cream significantly improved global clinical scores, increased skin microrelief density, and induced elastic tissue repair in photoaged skin compared to excipient control in healthy female volunteers.

  Experimental Dermatology, 2003

• Ascorbic acid 2-glucoside gel significantly reduced gingival melanin pigmentation after 4 weeks compared to placebo in 73 subjects with symmetric pigmentation.

  Journal of Periodontology, 2009

• Topical application of VC-IP cream twice daily for 8 weeks reduces periorbital wrinkles in female subjects compared to a placebo cream.

  Journal of Cosmetic Dermatology, 2022

• Topical post-laser application of human adipocyte-derived mesenchymal stem cell media combined with niacinamide significantly improved wrinkle index, melanin index, patient satisfaction, and investigator esthetic improvement scores compared to vehicle cream in patients with aging skin.

  Journal of Cosmetic Dermatology, 2021

• Topical nicotinamide prevented solar-simulated UV-induced immunosuppression in healthy volunteers, and men experienced immunosuppression at solar-simulated UV doses three times lower than those required for women.

  The Journal of Investigative Dermatology, 2008

• Topical 5% niacinamide applied twice daily for 12 weeks reduced fine lines and wrinkles, hyperpigmented spots, red blotchiness, and skin sallowness, and improved skin elasticity compared to vehicle control in 50 female white subjects with facial photoaging.

  Dermatologic Surgery, 2005

• Combining 755 nm alexandrite laser with topical licorice gel significantly reduces terminal hair counts compared to alexandrite laser with placebo in women with idiopathic hirsutism.

  Evidence-based Complementary and Alternative Medicine, 2015

• Licochalcone A activated Nrf2 signaling, elevated cytoprotective enzymes, increased the reduced-to-oxidized glutathione ratio, and decreased reactive oxygen species in human fibroblasts and neutrophils, while a LicA-rich licorice extract lowered UVA-induced oxidative processes in vivo.

  Experimental Dermatology, 2015

• Bioactive glycyrrhizic acid and oxymatrine ionic liquid self-assembled nanomicelles significantly promoted the transdermal permeation, subcutaneous retention, and anti-photoaging efficacy of palmitoyl pentapeptide-4 in cellular and animal models compared to unformulated peptide.

  Advanced Science, 2025

• Topical gel containing chitosan, 0.2% chlorhexidine, allantoin and dexpanthenol did not improve postoperative comfort regarding swelling and pain, but improved the wound's aesthetic appearance following impacted lower third molar extraction compared to no gel.

  Medicina Oral, Patologia Oral Y Cirugia Bucal, 2016

• A topical gel containing chitosan, chlorhexidine, allantoin, and dexpanthenol significantly reduced postoperative pain, trismus, swelling, and analgesic consumption, while improving wound healing after third molar surgery compared to a placebo.

  Medicina Oral, Patologia Oral Y Cirugia Bucal, 2020

• An overnight patch containing Allium cepa extract and allantoin safely promotes scar healing after dermatologic surgery, resulting in significantly greater reductions in observer- and patient-assessed POSAS scores compared to no treatment.

  Aesthetic Plastic Surgery, 2018

Ingredients

Citrus Junos Fruit Extract, Water, Niacinamide, Dipropylene Glycol, Glycerin, 1,2-Hexanediol, Sodium Polyacryloyldimethyl Taurate, Ppg-13-Decyltetradeceth-24, Butylene Glycol, Sodium Ascorbyl Phosphate, Dipotassium Glycyrrhizate, Allantoin, Carbomer, Panthenol, Ethylhexylglycerin, Tromethamine, Bergamot Oil Fruit, Sodium Phytate, Citrus Junos Peel Extract, Hippophae Rhamnoides Fruit Extract, Grapefruit Peel Oil, Sodium Hyaluronate, Caramel, Juniperus Mexicana Oil, Limonene, Linalool

Behind this fit score

Lovi calculates every fit score from the full ingredient list with brand-independent rules our dermatologists and cosmetic chemists build and review, and personalizes every pick with AI trained on the real results of millions of users. Lovi trains its fit score models on a proprietary dataset built from more than 10,000 expert-labeled products and more than 100,000 simulated examples, following an internally consistent methodology presented at Cosmoprof, AMWC, and Skin of Color Update.