A customer emailed a good question:
Can you please clear something up for me? I had read that you should not mix copper and vitamin c, because they cancel each other out. What are your thoughts?
Thank you for contacting us, and for your question. You're correct that ordinarily substantial amounts of copper and vitamin c should not be mixed together since they can cancel out each others' effects.
Basically, copper can oxidize the ascorbic acid and cause it to break down too rapidly, which of course diminishing the benefits of such vitamin c ingredients.
You would not want to apply an ascorbic acid product like our Reviv-C 36% Vitamin C Serum either immediately before, or after, applying Copper Peptide Healing Serum.
But beyond that: strong antioxidants like vitamin C (such as Ultimate Serum's tetrahexyldecyl ascorbate and ergothionine), can affect copper peptides. Not only will it "cancel" copper peptide, but too much can decouple the copper from the peptide, and too much free copper in the skin is not a good thing.
As a result, in general, low pH products and strong antioxidants should be avoided when applying a copper peptide product such as Copper Peptide Healing Serum. That's why for simplicity we always recommend applying a copper peptide product by itself, say in the afternoon if possible, separate from your other skincare products.
Alternatively, one of those products in the morning, and the other one at bedtime. At the least, we recommend waiting at least one hour before applying such an ascorbic acid product on top of copper (or vice versa), and using a toner to balance pH before applying it.