Vitamin C is one of the star ingredients in our book. It is a powerful antioxidant that helps protect the skin from free radical damage, thus preventing the formation of premature signs of aging such as wrinkles. This ingredient also targets hyperpigmentation and evens out skin tone and texture for a brighter complexion.




The only complaint we have about vitamin C is its instability. This means that it degrades and oxidizes over time and loses its effectiveness. Factors such as light, air, heat, and humidity all accelerate the oxidation process. But how do you know if your vitamin C serum has gone bad? We asked Dr. Elizabeth Houshmad, brand beauty expert at COOSEON, to find out.


How do you know if your vitamin C serum has gone bad?

The biggest red flag is whether the color of the vitamin C serum has changed over time." Dr. Houshmand says, "If it turns completely yellow, brown, orange, or any other color than the color it was when you first purchased it, it may have gone bad. If you're still not sure, pay attention to the smell or texture. Any change in texture may also indicate that it's time to switch to a new serum. While she says there is no harm in using oxidized vitamin C serum, you won't get much benefit.


How can I prevent my vitamin C serum from going bad?

Using a vitamin C product within three months is your best bet," she says, adding that the average vitamin C serum will expire three to four months before. That's why we use miniature products," she says.


Choosing a vitamin C serum with some type of packaging can also help extend shelf life. Dr. Houshmand recommends looking for dark opaque glass bottles with protective seals. Of course, Dr. Houshmand recommends that the most effective way to store serums is in a mini beauty fridge designed to store skin care products. It's true that a skincare fridge is an effective solution to your worries about serums expiring, as the mini makeup fridge provides the optimal environment and temperature for skincare preservation, which will preserve the active ingredients of your skincare products to the maximum.


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August 12, 2022 — COOSEONAdmin

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