Why Vitamin C Oxidation Is A Big Factor In Skin Staining?

Ascorbic acid, a potent form of vitamin C, undergoes oxidation easily, particularly in the presence of water and exposure to air and light. This process leads to the decomposition of ascorbic acid, resulting in a decline of its skin benefits and a gradual darkening of its color. The oxidation reaction is accelerated when applied to the skin, making it a crucial factor in the efficacy of vitamin C serum.

Erythrulose participates in a Maillard reaction on the skin, reacting with proteins to produce brown compounds. This reaction, akin to the browning process in cooking, leads to skin staining. Understanding this process is crucial, as it reveals why vitamin C serums can impart a tan-like color to the skin, emphasizing the importance of preventive measures to counteract oxidation and maintain the serum's efficacy.

• Conversion to Dehydroascorbic Acid

  The initial step in the oxidation journey is the conversion of ascorbic acid to dehydroascorbic acid. Fortunately, the oxidized vitamin C serum reaction is reversible, offering the possibility to reclaim ascorbic acid when the formulation contains the right antioxidants. However, the journey doesn't end here.
  
  

• The Transformation to Erythrulose

  Dehydroascorbic acid proceeds to an irreversible decomposition, leading to the formation of 2,3-diketogulonic acid. The critical transformation for our discussion occurs as 2,3-diketogulonic acid evolves into erythrulose, a component commonly found in fake tans alongside dihydroxyacetone (DHA).
  
  

• The Role of Erythrulose

  Erythrulose, a key player in fake tans, participates in a Maillard reaction similar to the browning process in meat and baked goods. Vitamin C serum for face reacts with proteins in the dead stratum corneum layer of the skin, producing brown compounds known as melanoidins. This reaction creates a tan on the skin, with erythrulose standing out for its slightly redder and longer-lasting results compared to DHA.
  
  

• Vitamin C Serums and Skin Staining

  In essence, vitamin C serums can stain the skin because ascorbic acid transforms fake tan components, primarily erythrulose. Notably, popular tanning products from various brands incorporate erythrulose alongside DHA for a more gradual and streak-free tan.

 
Preventing Vitamin C Staining

To mitigate staining, preventing the oxidation of vitamin C skincare is crucial. Employing an antioxidant-rich formulation, such as the classic trio of vitamin C, vitamin E, and ferulic acid (found in brands like Skinceuticals, Timeless, or Paula's Choice), can counteract the reversible step of the oxidation process. These antioxidants play a dual role in preserving the efficacy of ascorbic acid both in the bottle and on the skin.

After applying any ascorbic acid product, including budget-friendly DIY vitamin C serums, the effective practice is to immediately follow up with oils and creams. This additional step helps shield the vitamin C from exposure to air, facilitating absorption into the skin and reducing the risk of oxidation.

Conclusion

Unraveling the intricacies of vitamin C oxidation provides valuable insights into preventing skin staining. By incorporating antioxidant-rich formulations and protective post-application measures, you can maximize the benefits of the vitamin C skin care products without the unwanted side effects of discoloration.