Ingredient glossary
THD Ascorbate
On your shelf ✓What THD Ascorbate does for your skin, who it suits, and what to watch for.
INCI: Tetrahexyldecyl Ascorbate · Also: Tetrahexyldecyl Ascorbic Acid
In short: THD Ascorbate delivers brightening and antioxidant, suits most skin types, and the evidence behind it is moderate. One thing to know: needs the right pH to work.
- What it does
- Brightening, antioxidant
- Best for
- Most skin types
- Watch out
- Needs the right pH to work
- Evidence
- Moderate
- How long
- Never measured
The molecule
The Glow take
One of the ingredients I trust most.
When your goal is fading dark spots and evening out tone, THD Ascorbate delivers, with a solid amount of evidence behind it. It only performs at the right pH, so it is worth buying from brands that get the formulation details right.
— Maya
What it does
- brightening
- antioxidant
- anti aging
moderate evidenceIn vitro models and small clinical trials with thirty percent serum show meaningful melasma and tone improvement but the overall evidence base is still modest.
On a label: usually effective at 5-30%.
Who it's for, and who should skip it
Tends to suit
- normal
- combo
- oily
- dry
- pigmentation
- photoaged
Approach with care
- very sensitive
- Clogs poresLow
- Irritation riskLow
- pH-dependentIts effect depends on the product's pH
How it fits each skin type
- DrySuits
- CombinationSuits
- OilySuits
- SensitiveTake care
Often chosen for pigmentation, photoaged.
Where it fits in your routine
Nobody has published how long this takes to work.
What is known, and what is missing
Measured on: pigment/tone and wrinkle improvement in photoaged skin; no vehicle-controlled human time course.
Used at 5-30% as the oil-soluble ascorbate ester, but the human work does not isolate it. An 8-week randomised double-blind study photographed at 0, 4 and 8 weeks compared THD ascorbate plus acetyl zingerone against THD ascorbate alone with no vehicle arm, and reported that the THD-alone arm's wrinkle severity and erythema rose; a 12-week open-label study used a multi-ingredient THD serum with no control at all. Missing: a vehicle-controlled trial with interim visits showing when THD ascorbate alone moves melanin index or wrinkle grade.
Afzal et al., J Cosmet Dermatol 2024, 'Prospective randomized double-blind comparative study of topical acetyl zingerone with tetrahexyldecyl ascorbate versus tetrahexyldecyl ascorbate alone on facial photoaging', PMID:38525606; Min et al., J Cosmet Dermatol 2024, open-label 12-week THDA + acetyl zingerone serum.
Plays well with
- niacinamide
- vitamin e
- ferulic acid
- sunscreens
THD Ascorbate, answered
Is THD Ascorbate safe during pregnancy?
Yes. THD Ascorbate is considered safe to use during pregnancy and breastfeeding. As with anything, if you are unsure it is worth a quick word with your doctor or midwife.
Who should avoid THD Ascorbate?
Approach THD Ascorbate with care if any of these apply to you: very sensitive.
What concentration of THD Ascorbate actually works?
THD Ascorbate tends to do its job in the 5 to 30% range. Much lower and it is likely underdosed.
Commonly confused with
- Vitamin C (LAA)Pure vitamin C is the strongest but least stable. THD ascorbate is an oil-loving derivative that trades some punch for a gentler, steadier feel.
Compare THD Ascorbate with
- Niacinamide
- Vitamin C (LAA)
- Retinol
- Retinal
- Hydroxypinacolone Retinoate
- Retinyl Palmitate
- Retinyl Acetate
- Retinyl Propionate
- Retinyl Retinoate
- Azelaic Acid
- Tranexamic Acid
- Kojic Acid
- Phytic Acid
- Sodium Ascorbyl Phosphate
- Magnesium Ascorbyl Phosphate
- Ascorbyl Glucoside
- Ethyl Ascorbic Acid
- Palmitoyl Pentapeptide-4
- Palmitoyl Tripeptide-1
- GHK-Cu
- Argireline
- Bakuchiol
- PDRN
- Alpha Arbutin
- Caffeine
- Hydroquinone
- Galactomyces Ferment Filtrate
- Rice Extract
- Thiamidol
- Cysteamine
- N-Acetyl Glucosamine
- Adenosine
- Tetrahydrocurcumin
- Leuphasyl
- Rigin
- Matrixyl Synthe'6
- Syn-Ake
- Exosomes
- Epidermal Growth Factor
- Colostrum
- Carnosine
- 4-n-Butylresorcinol
- 4-Hexylresorcinol
Can you mix THD Ascorbate with
This, for every label you own
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