No, it does not. It may stain your skin but it cannot darken your skin. It is important to know the difference between staining and darkening the skin. Staining is where the product reacts with your dead skin cells and leads to a change in the color of those dead cells.
An oxidized bottle of vitamin C (not only has the serum turned dark brown, but the rubber dropper has also started to dissolve). After contact with light, heat and air, vitamin C eventually oxidizes and loses its potency. You'll know it when your serum changes colour, turning brown.
Vitamin C lightens skin by inhibiting the amount of melanin your pigment skin cells generate. When applied topically, vitamin C interacts with tyrosinase, the main enzyme responsible for the conversion of the amino acid tyrosine into melanin, thereby reducing pigmentation.
Vitamin C preparations can also discolor on the skin surface as they contact oxygen in the environment. This accounts for the orange color that may emerge on the skin in the morning after wearing a vitamin C preparation overnight.
However, anecdotal evidence suggests vitamin C might increase melanin levels. Eating vitamin C–rich foods like citrus, berries, and leafy green vegetables may optimize melanin production. Taking a vitamin C supplement may help as well.
Vitamin C serum can help with freckle removal, but some freckles are more persistent than others. Certainly, however, when applied in serum form Vitamin C does lighten freckles.
For a bright and glowy complexion, skin enthusiasts are now reaching for the latest holy grail, Vitamin C. Safe to use for most skin types (including melanated skin!), this powerful antioxidant is known to boost cell turnover, increase collagen production, and even out skin tone.
Now consider vitamin C serums for facial anti-aging purposes. When in the vitamin C is in high concentration, the serum will have a yellowish color; but as it oxidizes, it will turn brown/orange.
Unlike hydroxyacids or retinol, vitamin C does not make the skin more vulnerable to sunburn. That being said, the most potent forms of vitamin C are vulnerable to light exposure, and therefore the use of vitamin C must be in conjunction with broad-spectrum UVA/UVB coverage.
Vitamin C-based skin care products may lighten patches that are darker than the rest of your skin, called hyperpigmentation. In one study, vitamin C applied to the skin for 16 weeks significantly cut down on these spots. But experts say it will take more research to confirm how well vitamin C creams work.
Vitamin C serum benefits
If you're wondering when to apply a vitamin C serum, the answer is both morning and night, after cleansing and toning. One study even recommends applying a vitamin C serum every eight hours, or twice daily for the pinnacle of protection.
How do they do it? Some sources indicate that they use chemical peels, surgery or lasers to whiten their skin. In fact, some strong creams such as Benaquin are used as well as drugs that can inhibit production of melanin.
Even if you don't have sensitive skin, we recommend that all skin types use their vitamin C serum before bed. Your body undergoes its natural repair process while you're asleep, and the vitamin C will make its strongest impact on your skin during this time.
Vitamin C serums usually take longer than other serums to show results. But if used regularly, it will start showing results in four to twelve weeks.
Saedi recommends vitamin C serums for people of all ages because virtually everyone is at risk of sun damage, and with vitamin C serums “we are minimizing the amount of sun damage that our skin's getting from sunlight,” she says.
“Your vitamin C serum should be colorless or a light straw color; if it oxidizes, it becomes yellow or brown and is likely going to be less effective.” You can still use it if you want, but it probably won't do as much for your skin and, “very rarely, oxidized vitamin C products can even cause slight yellow ...
You don't have to toss a serum if it's only slightly yellow but if it's tipping into orange, it's time to bin it. A dark orange would mean that your Vitamin C has over-oxidised and has lost a huge percentage of its efficacy.
Also, we consulted with scientists who told us that if you wear vitamin C without sunscreen, your vitamin C can actually be photo-incinerated (i.e. totally burned away) by the sun.
Use a water based or non comedogenic moisturizer which means it doesnt clog your pores. AcneOC is a good one which is light, non-greasy and non comedogenic.