Tetrahexyldecyl Ascorbate
Also known as: THD Ascorbate, Lipophilic Vitamin C, INCI: Tetrahexyldecyl Ascorbate
Oil-soluble vitamin C derivative that brightens and protects skin with improved stability versus L-ascorbic acid.
See this ingredient in your own products — scan the label.
Get the appWhat it does
A fat-soluble form of vitamin C that penetrates lipid-rich skin layers more effectively than water-soluble versions. It converts to active ascorbic acid in skin and provides antioxidant protection against environmental oxidative stress. Known for superior shelf stability and less degradation than pure L-ascorbic acid.
Benefits
- Brightens dull complexion and evens tone over time
- Potent antioxidant protection against free radicals and UV damage
- More stable and shelf-stable than L-ascorbic acid forms
- Supports collagen production and skin firmness
- Less irritating than some vitamin C alternatives for sensitive users
Who it suits
- Dull or uneven-toned skin
- Mature skin seeking antioxidant support
- Oily to combination skin (oil-soluble form)
- Sensitive skin preferring gentler vitamin C
How to use
Apply 2-3 drops of serum to clean, dry skin morning or evening, or as directed by product instructions. Follow with moisturizer and always use broad-spectrum SPF during daytime use.
Pairs well with
Vitamin E (synergistic antioxidant boost), Ferulic acid (enhances stability and efficacy), Hyaluronic acid (adds hydration layer), Niacinamide (supports barrier health)
Be careful pairing with
Niacinamide in unstable formulas (though modern formulations often combine them), High-pH products (degrades vitamin C)
Safety & cautions
Generally well-tolerated, but vitamin C products can sensitize skin to sun exposure—always use SPF during the day. Efficacy depends on formulation pH and stabilization; not all products deliver bioavailable results.
Educational information, not medical advice. Concentration and formulation change how an ingredient behaves.