Vitamin C is one of the most researched skincare ingredients in existence. It’s also one of the most misunderstood — largely because the form of Vitamin C matters enormously, and most products don’t explain which form they’re using or why.
Here’s the honest guide.
Why Vitamin C Is Worth Having in Your Routine
Vitamin C (ascorbic acid) is the most potent antioxidant naturally present in human skin. It serves three primary functions:
Brightening: Inhibits the enzyme tyrosinase, which is responsible for melanin production. This reduces existing hyperpigmentation and prevents new dark spots from forming — including post-blemish marks and sun damage.
Collagen synthesis: Vitamin C is essential for the hydroxylation of proline and lysine — the chemical process that creates the triple helix structure of collagen. Without adequate Vitamin C, collagen cannot form properly.
Antioxidant protection: Neutralises free radicals generated by UV exposure, pollution and oxidative stress — the primary environmental causes of premature skin ageing and dullness.
The Problem With Pure Ascorbic Acid
Pure ascorbic acid (L-ascorbic acid) is the most potent form of Vitamin C but also the most unstable. It oxidises quickly on exposure to air and light, turning the formula yellow-orange and losing effectiveness. It’s also irritating at the concentrations needed for efficacy — particularly on sensitive skin.
Why We Use Ascorbyl Glucoside
Ascorbyl Glucoside is a stable ester of Vitamin C — a glucose molecule bonded to ascorbic acid. When applied to skin, enzymes in the skin gradually cleave the glucose molecule, releasing pure ascorbic acid slowly and consistently over time.
The advantages: dramatically more stable than pure ascorbic acid (no oxidation, no colour change), less irritating (the slow release prevents the spike in concentration that causes sensitivity), and equally effective for long-term brightening when used consistently.
The trade-off: it works more slowly than high-concentration pure ascorbic acid. For immediate, dramatic results, pure Vitamin C at 15–20% is faster. For consistent, progressive brightening with better tolerability and stability, Ascorbyl Glucoside is the better choice.
In the Glow Base Radiance Serum
We use Ascorbyl Glucoside in combination with niacinamide and peptides. The combination matters: niacinamide inhibits melanin transfer while Vitamin C inhibits melanin production — two complementary approaches to the same brightening outcome. Peptides support the collagen framework that Vitamin C helps build.
Used daily over 8–12 weeks, the combination produces measurable improvements in skin brightness, evenness and texture that individual ingredients alone cannot replicate at comparable concentrations.