Adding Vitamin C to Vitamin C E Ferulic Premix Kit: Solubility and Irritation

Subject: Regarding adding Vitamin C to the Vitamin C E Ferulic premix kit

Thank you for your question. You are asking about adding an additional 5% L-ascorbic acid (Vitamin C) to the Vitamin C E Ferulic premix kit and how to adjust the formula.

Based on the information from our staff, the Vitamin C E Ferulic premix kit is specifically designed and optimized to dissolve 15% L-ascorbic acid. Adding more than the recommended amount may lead to issues.

While some users have reported being able to dissolve higher concentrations (up to 18% or even 20% as you experienced), it's important to consider the potential downsides mentioned in the conversation:

• Solubility: The base is formulated for 15%. While a higher amount might dissolve initially, it could affect the long-term stability of the solution or lead to recrystallization.
• Stability: L-ascorbic acid is prone to oxidation, which causes it to lose effectiveness and turn yellow. Higher concentrations can be less stable and degrade faster, as noted by user sawalee49.
• Skin Irritation: Increasing the concentration of L-ascorbic acid lowers the pH of the solution, which can cause significant skin irritation, redness, and stinging, as experienced by user sawalee49. Individual tolerance varies, as you observed, but higher concentrations generally increase the risk of irritation.
• Effectiveness: While research suggests 20% Vitamin C might have better absorption than 15%, consistent use at a well-tolerated concentration (like 15%) is often more beneficial than intermittent use at a higher concentration that causes irritation and requires breaks, as pointed out by user cosmeceutical7.

Modifying a pre-designed premix kit formula by adding more active ingredients is generally not recommended. The kit's formulation is balanced for optimal solubility, stability, and efficacy at the intended concentration. Altering this balance can compromise the product's performance and potentially cause adverse skin reactions.

Therefore, even if you can dissolve the extra Vitamin C, it is advisable to stick to the recommended 15% concentration for the best balance of effectiveness, stability, and skin tolerance with this specific kit.