Member exclusive Q&A: What’s a cosmeceutical? What’s an active? And how much can we use of these things in combination? Part five – the formula (updated)

Over the last few days, we’ve been looking at cosmeceuticals to find some kind of answer to the question – what’s the limit on using these kinds of active ingredients? Yesterday, we looked at some ingredients we might like to use together to see if they were compatible. They were, so let’s take a look…