Hi I was wondering if glutathione could be used as a daily antioxidant instead of ascorbic acid as it is more stable and less irritating.
It is an option, especially if you are looking for anti-pigmentation effect. It might still be irritating - so please watch your skin reaction closely. Another potential downside can be worsening of acne if you suffer from any. I didn't dig too deep into it, but this study reported this as a side effect. Effective concentration for the anti-pigmentation effect for glutathione is around 0.5%.
Thanks for the fast reply!