Yonka Vitamin C Serum 20% — Concentrated Brightening & Firming Serum, 0.17 fl oz (Stabilized Oil-Soluble Vitamin C)

Yon-Ka 20% Vitamin C Serum is a highly concentrated facial treatment that brightens uneven tone, helps firm texture, and supports collagen production using a stabilized, oil-soluble vitamin C formula.

This lightweight serum delivers a 20% concentration of stabilized Vitamin C (ascorbyl tetraisopalmitate) in a formula composed almost entirely of natural-origin ingredients. Designed for daytime and evening use, it pairs botanical cell actives—like turmeric and pomegranate—with a green-science vitamin C derivative to target hyperpigmentation, loss of firmness, and dullness without heavy residues. Clinical monitoring shows measurable improvements in tone evenness and a reduction in uneven patches with twice-daily application.

How fast will I see improvements in skin tone and texture?

Visible changes depend on starting condition and consistency, but Yon-Ka’s monitored use study reported measurable improvements within four weeks and continued progress by eight weeks. Results often appear first as increased radiance and gradual fading of dark spots.

• Instrumental testing showed a marked increase in tone evenness after 28 days.
• Further reduction in uneven patches was recorded at 56 days with continued use.
• Expect subtle radiance within 1–4 weeks; more significant correction by 6–8 weeks.

Can this serum work with my other skincare steps or procedures?

The Yon-Ka vitamin C serum is formulated to integrate smoothly into most routines and can be used alone or under creams, morning and night. It is also suitable as an intensive course after clinical procedures when recommended by your professional, though you should follow post-procedure guidance for active ingredient use.

• Apply to clean skin before moisturizer for daytime or nighttime routines.
• Compatible with creams and many serums; patch-test if layering strong actives.
• May be used as a post-procedure adjunct when cleared by your clinician.

Is this Vitamin C stable and suitable for sensitive skin?

This serum uses ascorbyl tetraisopalmitate, an oil-soluble, stabilized form of Vitamin C derived by green-science methods, chosen for better skin compatibility and longer shelf stability compared with ascorbic acid. Formulated with plant cell actives and a high percentage of natural-origin ingredients, it aims to reduce irritation risk while delivering potent antioxidant benefits.

• Uses stabilized, oil-soluble Vitamin C for improved tolerance and persistence on skin.
• Contains botanical actives (turmeric, pomegranate) to support firmness and tone.
• High natural-origin content minimizes synthetic fillers but perform a patch test if extremely reactive.

Who is this for: Yon-Ka 20% Vitamin C Serum is intended for anyone seeking targeted correction of dark spots, dullness, and early signs of aging—particularly those who prefer high-efficacy, naturally derived actives in a professional-grade formulation. It is suitable for individuals looking to boost radiance, support collagen production, and even skin tone with a concentrated, lightweight treatment. If you have sensitive or highly reactive skin, consult a dermatologist before introducing potent active serums and consider starting with less frequent application while your skin adapts.

• Key actives: 20% ascorbyl tetraisopalmitate, turmeric cells, pomegranate cells.
• Texture & use: Lightweight serum for AM and PM; layer under moisturizer.
• Clinical context: Dermatologist-monitored improvements noted at 28 and 56 days in a Yon-Ka study.