You remember that time when every skincare guru on the internet couldn’t stop talking about Vitamin C? I loaded up on the ingredient and now have a whole Vitamin C stash – one that could rival a small pharmacy!
But a few days ago, I realised the colour of one Vitamin C serum had changed to a deep yellow and ngl, it kind of freaked me out. So like every other 2000s kid raised by the internet, I took to Instagram to figure out if there was something wrong with my serums.
And you’ll never believe what I found.
My Vitamin C Serum Had Oxidised!
Like every other cosmetic product on the market, Vitamin C also has a shelf life. What I didn’t know though, is that it has a tendency to oxidise faster than other products—and ideally should be used within 3-6 months of opening.
What Does ‘Oxidise’ Mean?
When your Vitamin C serum has been exposed to oxygen, extreme heat, or extended exposure to light (especially ultraviolet rays), it oxidises. The oxidation process leads to the degradation of vitamin C and the loss of a myriad of beneficial properties.
How To Tell If Your Vitamin C Serum Has Oxidised
A telltale sign of oxidised Vitamin C is the change in its colour. Most serums are either transparent or light yellow; if the colour of your serum is a dark yellow or brown, you can take it as a pretty clear indication that your product has oxidised.
If you’re still unsure, take note of any scent or texture changes—these are also signs that it’s time for a fresh serum. Remember, Vitamin C has a pretty distinct smell anyway so you’re not looking for something unusual, you’re just looking to see if the smell has changed since you’ve started using it.
Can You Still Use Oxidised Serum?
While oxidised serum won’t cause any intense reactions in most people, the effectiveness is pretty much non-existent. Since the active no longer contains the right potency, it is unable to protect the lipid barrier of your skin and therefore, cannot protect your skin from further damage.
In some rare cases, applying oxidised vitamin C to the skin can also lead to discolouration and yellowing of the skin.
If your skin feels irritated after using an oxidised or expired serum, you can try a hydrocortisone 1% cream. Apply it twice a day for 3-5 days on the areas of irritation and itching. But make sure to dial your dermat, before you make these decisions!
Here are some Vitamin C serums that are a part of my stash:
Even the best skincare superheroes have their kryptonite and for Vitamin C, turns out, it’s the ticking clock of oxidation. If it’s yellow, it’s time to ditch the bottle and buy a new one.
Featured Images: Pexels
