Key Ingredients in CITY Brightening Vitamin C Face Oil
Licorice Extract (Glycyrrhiza Glabra Root Extract)
Vitamin C Tetrahexyldecyl (THD) Ascorbate
Hemisqualane
Frequently Asked Questions
Can vitamin C serum cause breakouts?
Traditional vitamin C serums can cause breakouts in some people due to low pH formulations or unstable forms that oxidize quickly. City uses tetrahexyldecyl ascorbate — an oil-soluble, stable form of vitamin C that works at a skin-friendly pH and doesn't trigger the irritation or congestion associated with L-ascorbic acid. It's non-comedogenic and suitable for acne-prone skin.
Can vitamin C serum cause redness or irritation?
L-ascorbic acid, the most common vitamin C form, requires a low pH to be effective and frequently causes stinging, redness, or peeling — especially on sensitive skin. City uses tetrahexyldecyl ascorbate instead, which is oil-soluble, pH-independent, and penetrates deeper without irritation. It brightens and protects without any of the reactivity that puts people off vitamin C serums.
Does vitamin C serum expire or go bad?
Yes — most vitamin C serums use L-ascorbic acid, which oxidizes quickly when exposed to light and air, turning orange and losing effectiveness. City uses tetrahexyldecyl ascorbate, a stable oil-soluble form that doesn't degrade the same way. Stored away from direct sunlight, City maintains its potency significantly longer than conventional vitamin C formulas.
What does a brightening serum do?
A brightening serum targets uneven skin tone, dullness, and hyperpigmentation using ingredients that interrupt melanin production or neutralize the oxidative damage that causes skin to look tired. City combines vitamin C, niacinamide, and licorice root extract — three brightening pathways working simultaneously — alongside a full antioxidant system that protects against the pollution and UV exposure that cause dullness in the first place.
When should you use vitamin C serum in your routine?
Morning is ideal — vitamin C is an antioxidant that neutralizes free radical damage from UV and pollution throughout the day, so it works best as a preventative layer before sunscreen. Apply City after cleansing and any water-based serums, then follow with SPF. It can also be used in the evening, and pairs well with a hydrating serum applied underneath.
What are free radicals in the skin?
Free radicals are unstable molecules missing an electron. To stabilize themselves, they take electrons from healthy skin cells, setting off a chain reaction that can damage collagen, cell membranes, and DNA along the way. Skin produces them constantly — UV exposure, urban pollution, and normal metabolism are the main sources — and when they outpace the skin's own defenses, the result is oxidative stress, which shows up as dullness, uneven tone, and premature signs of aging. Antioxidants like vitamins C and E help by donating an electron to a free radical without becoming unstable themselves, which interrupts the chain reaction. City's antioxidant system is built around exactly this.
As Seen In
