Has your vitamin C serum gone bad?

Vitamin C is a great antioxidant that brightens and energizes the skin, but of all the skincare serums, it probably has the shortest shelf life. Once the product is opened and comes into contact with oxygen, it starts to degrade, so it's very important to put the cap back on and tighten it properly and quickly.

The easiest way to tell if your serum is old is to look at the color. Most vitamin C serums are clear in color. They tend to eventually change color from yellowish to brown. This process takes a couple of months and is a sign that the L-ascorbic acid is losing its effectiveness.

It is not a great idea to use vitamin c serum that is oxidized, you will not get the effect you are looking for and you may instead get skin irritation. Follow your skin therapist's advice on how and when to use your serum :-)