C Complex Serum 30 ml

The C Complex Serum by Josh Rosebrook does not rely on a single, highly concentrated form of vitamin C, but on a thoughtfully designed antioxidant network. Tetrahexyldecyl Ascorbate (THDA) and 3-O-Ethyl-L-Ascorbic Acid are two more stable vitamin C derivatives with different properties: THDA is oil-soluble, while 3-O-Ethyl-L-Ascorbic Acid is water-soluble. Together, they deliver vitamin C in a lightweight, well-tolerated serum that makes dull skin look fresher, evens out an uneven skin tone, and improves the appearance of dark spots.

• Product type: antioxidant vitamin C serum for the face and neck
• Skin types: suitable for all skin types; especially dull, uneven-looking or blemish-prone skin
• Key benefits: supports a more even skin tone, increased radiance and smoother-looking skin texture
• Vitamin C complex: oil-soluble Tetrahexyldecyl Ascorbate plus water-soluble 3-O-Ethyl-L-Ascorbic Acid
• Antioxidant network: vitamin C is complemented by ferulic acid and vitamin E
• For a more even complexion: with azelaic acid and licorice root
• Texture: lightweight, hydrating, fast-absorbing and non-sticky
• Quality: made with numerous certified organic botanical ingredients, vegan, cruelty-free, made in the USA

Ferulic acid and vitamin E complement the two forms of vitamin C with additional antioxidant support. Azelaic acid and licorice root also target areas where the complexion appears unsettled or uneven. Tamanu, rosehip, avocado and meadowfoam oils provide nourishing lipids without making the serum feel heavy.

Hydration is also exceptionally thoughtfully formulated: aloe vera, glycerin, hyaluronic acid and Irish moss help retain water in the skin and give it greater softness and plumpness. As a result, the C Complex Serum feels less like a classic acidic vitamin C serum and more like a lightweight, silky active treatment that combines antioxidant protection, a more even complexion and hydration.

Key ingredients

• Tetrahexyldecyl Ascorbate (THDA) is an oil-soluble and exceptionally stable form of vitamin C. Its lipophilic structure allows it to integrate particularly well into the skin's lipid-rich areas. There, it complements the skin's natural antioxidant defense mechanisms and supports a smoother, more even and more radiant-looking complexion. The combination of good stability and lipid solubility makes THDA an interesting alternative to classic L-ascorbic acid.
• 3-O-Ethyl-L-Ascorbic Acid is a water-soluble vitamin C derivative in which an ethyl group stabilizes the sensitive molecular structure and protects it from rapid oxidation. It therefore combines the cosmetic properties of vitamin C with significantly improved formulation stability. The ingredient supports the skin's antioxidant defense and helps improve pigmentation irregularities, a dull complexion and visible signs of photoaging.
• Ferulic acid and vitamin E provide antioxidant reinforcement for the vitamin C complex. Ferulic acid is a plant-based polyphenol that can neutralize free radicals and is often combined with vitamin C and vitamin E for precisely this reason. Vitamin E is oil-soluble and protects the skin's lipid structures in particular from oxidative stress. Together, they create a broader antioxidant network than vitamin C alone.
• Azelaic acid and licorice root specifically complement the formula for an uneven skin tone. Azelaic acid influences melanin production processes and is therefore especially valued for visible pigmentation changes and skin that appears uneven after inflammation. Licorice contains glabridin and other flavonoids, among other compounds, which are also known for their soothing and balancing properties. The combination makes the serum particularly interesting for dark spots, traces of previous blemishes and an overall unsettled complexion.
• Aloe vera, glycerin, hyaluronic acid and Irish moss ensure that the powerful active-ingredient combination does not come at the expense of skin comfort. Glycerin and hyaluronic acid bind water in the stratum corneum, while aloe vera and the polysaccharides of the red algae Irish moss additionally retain moisture and leave a fine, smoothing film on the skin.
• Tamanu, rosehip, avocado, sunflower and meadowfoam oils bring an unusually versatile lipid component to the serum. Tamanu oil is rich in distinctive plant compounds and fatty acids, rosehip oil primarily provides linoleic and alpha-linolenic acids, while meadowfoam oil is valued for its especially oxidation-stable long-chain fatty acids. Together, the oils keep the skin supple and balance the formula's highly active antioxidant properties.

How to use

• Use morning and/or evening after cleansing, toner and hydrating skincare.
• One to two pumps and gently press onto the face and neck.
• Then apply face oil and/or cream depending on your skin's needs.
• In the morning, always finish your routine with a suitable sunscreen.
• Store the serum protected from light and preferably in a cool place. A slight change in color over time may occur due to the botanical extracts it contains and does not mean that the stabilized vitamin C actives have lost their effectiveness.
• As with any new active skincare product, very sensitive skin should first perform a tolerance test.

Discover more vitamin C skincare in our Face care with vitamin C collection.

FAQ

Why does the C Complex Serum contain two different forms of vitamin C?
The two vitamin C derivatives have different solubility properties. Tetrahexyldecyl Ascorbate is oil-soluble, while 3-O-Ethyl-L-Ascorbic Acid is water-soluble. This allows vitamin C to be incorporated into skincare in different ways within a single formulation. Both forms are also significantly more stable than pure L-ascorbic acid.

What concentration of vitamin C does the serum contain?
Josh Rosebrook deliberately does not publish individual percentages. The brand develops its products as complete formulations and does not evaluate their effectiveness solely on the basis of the highest possible active-ingredient concentrations. In the C Complex Serum, the focus is therefore on the two vitamin C derivatives and their interaction with ferulic acid, vitamin E, azelaic acid and licorice.

Is a high concentration of vitamin C automatically better?
No. In addition to concentration, the form of vitamin C used, its stability, solubility, delivery system and combination with other antioxidants also play important roles. A particularly high percentage alone therefore says little about the quality of a serum.

Does the serum help with dark spots?
The C Complex Serum is specifically formulated for an uneven complexion. Vitamin C, azelaic acid and licorice root act at different points in pigmentation and the skin's antioxidant protection and, with regular use, can help make dark spots less visible and the complexion look more even overall.

Is the C Complex Serum an acid peel?
No. Although azelaic acid and citric acid are included, the product is not a classic AHA or BHA peel. The focus is on antioxidant care, radiance and a more even skin tone.

Can sensitive skin use the serum?
In principle, the serum is suitable for all skin types. Its vitamin C derivatives are stable, and the formula also contains numerous hydrating and nourishing ingredients. However, it contains a small amount of orange essential oil. Very sensitive skin or skin that reacts to essential oils should therefore first test the product on a small area.

Can I combine the C Complex Serum with retinoids?
Yes. Vitamin C derivatives and retinoids can generally be part of the same skincare routine. For sensitive skin, it may be more comfortable to use vitamin C in the morning and retinoids in the evening, or to introduce the actives on alternating days at first.

Why should I use sunscreen despite using vitamin C?
Antioxidants complement protection against oxidative stress but do not replace sunscreen. Especially when dark spots and photoaging are the focus, daily broad-spectrum protection is an essential part of skincare.

Josh Rosebrook

Josh Rosebrook combines modern cosmetic actives with high-quality botanical skincare and develops its formulations independently, without pressure from external investors. Rather than marketing individual ingredients primarily through high percentages, the focus is on how the entire formula works together - the C Complex Serum is a particularly characteristic example.

Ingredients

Water, *Aloe Barbadensis (Aloe Vera) Leaf Juice, Glycerin, Chondrus Crispus (Irish Moss) Extract, 1,2-Hexanediol, Hydroxyacetophenone, Sodium Hyaluronate (Hyaluronic Acid), Tetrahexyldecyl Ascorbate (Vitamin C), *Helianthus Annuus (Sunflower) Seed Oil, Limnanthes Alba Seed Oil, 3-O-Ethyl-L-Ascorbic Acid (Vitamin C), *Calophyllum Inophyllum (Tamanu) Oil, Disteardimonium Hectorite, Polyglyceryl-2 Isostearate, Polyglyceryl-6 Polyricinoleate, Ferulic Acid, *Olea Europaea (Olive) Fruit Oil, Caprylic/Capric Triglyceride, Azelaic Acid, *Glycyrrhiza Glabra (Licorice) Root, Sodium Citrate, *Rosa Canina (Rosehip) Seed Oil, *Persea Gratissima (Avocado) Oil, Citric Acid Anhydrous, Tocopherol (Vitamin E), Polyglyceryl-10 Laurate, Xanthan Gum, Phenethyl Alcohol, Ethylhexylglycerin, Leuconostoc/Radish Root Ferment Filtrate, *Citrus Sinensis (Orange) Oil.

*Certified Organic