Research has established that Vitamin C, in the proper form, can restore a smooth surface and a youthful glow to aging skin. In order to achieve these benefits, studies at Duke University show that a formulation of Vitamin C must possess the following characteristics:

• It must contain L-Ascorbic acid
• It must be at at acid pH
• It must contain a high concentration of L-Ascorbic acid.
• The L-ascorbic acid must be stable.

The only product to fit this criteria are SkinCeuticals serums:

• CE Ferulic
• Serum 10
• Serum 15
• Serum 20
• C+AHA