Vitamin C is a very popular skincare ingredient, but it also has a tendency to oxidize once opened.
If you’ve ever opened up a bottle of vitamin C serum only to find that it’s gone bad, you may have wondered: what happens if you use expired vitamin C serum?
Will your skin get worse or better?
Does the product simply stop working or will it cause some serious damage?
In this post, we’ll answer all these questions and more so that you can keep your skin looking its best—even if you’re using an old bottle of our favorite antioxidant-packed products!
How Long Does Vitamin C Serum Last Once Opened?
When you first open your vitamin C serum, it’s best to use it within three months.
Although vitamin C does not expire, it does lose its potency over time.
To keep your serum from losing its effectiveness and efficacy, store the product in a dark place in the refrigerator or freezer.
If you don’t have room for your serums to sit on shelves and shelves in the fridge, consider using an airtight container like Tupperware or a ziplock bag with a small amount of water at the bottom (this will increase oxygen exposure).
If you plan on using up all of your serum during these three months and want to prevent any waste, here are some tips on how to do that:
Use sunscreen when applying vitamin C products on top of sunburns or wounds – this can help prevent peeling by keeping moisture levels high enough so that cells don’t separate too quickly.
You may also want to apply sunscreen underneath products containing vitamin A as well.
Even though they’re both antioxidants that protect against free radicals like UVB rays do as well as other sources such as pollution/smoking/pollution (and car exhaust), they’re both still strong enough individually without being combined together!
Apply the product sparingly
Only use what you need for each application (i.e., apply a small amount directly to your face and neck) and then wait until it dries before adding a second layer (if needed).
If you have sensitive skin, try mixing in a few drops of water or witch hazel with the product before applying it directly onto your skin.
What Happens if You Use Expired Vitamin C Serum?
- You risk skin irritation and inflammation.
- Using expired Vitamin C serum can cause redness and irritation on your face, especially if you use it on sensitive areas like around the eyes, mouth, and nose.
- Treating acne with expired products may also cause more breakouts instead of less because the product is no longer effective at fighting bacteria or reducing swelling in pimples.
How Do You Know if Vitamin C Serum is Expired?
Vitamin C serum lasts a long time if stored properly.
But it will lose its potency once opened, so you should use it within six months to a year after opening it.
Here are some ways to know if your vitamin C serum has gone bad:
- The color changes
- It smells funny
- It separates out into layers (oil and water)
- It turns yellow or brownish/orangey
- It turns cloudy or greyish/white (cloudy or milky)
When Should You Throw Out Vitamin C Serum?
After you open a bottle of vitamin C serum, you’ll want to use it within 12 months.
It’s important that you keep your bottle in a cool, dark place and away from heat and moisture.
If there are no signs of spoilage (such as mold or foul odor), this means the product is still good to go!
We hope this article has helped you learn more about how long vitamin C serum lasts once you open it.
As we discussed, there are many factors that affect the lifespan of your beauty products, so it can be difficult to know exactly how long something will stay fresh before it expires.
However, there are some guidelines we recommend following so that you can avoid any unpleasant surprises down the road (like having to throw away your favorite moisturizer).
If possible, buy smaller sample sizes at first until you get an idea of how long each product lasts under normal usage conditions; then make an informed decision about whether or not it’s worth buying full-size bottles later on down the road!