Olaplex.

"I did one on Olaplex in 2018 and in it, I messed up. I went through how Olaplex claimed their product worked, and there was and still is a bit of controversy around this. But more publications and a lot more products have come out since then. Products with ingredients that cannot work that way seem to give similar results to Olaplex, so it is probably not how it works."

"If you do not have damaged hair that's permed or color treated or damaged from heat objects like curling irons and things like that, Olaplex could actually do more damage for your hair than good. Apparently hair that is damaged has less protein and keratin in it. That's why you use things like Olaplex or K18 mask to help heal those damaged bonds. But if you don't have damaged hair, you have healthy hair, you don't color it, you don't really heat treat it, using Olaplex for too long can actually make your hair worse, can make it more breakage, break at the ends, split ends. If you have hair that's not been treated by color, bleaching, things like that, you're probably better off just going with a normal shampoo and conditioner as opposed to some of these protein building shampoos because you can really get your hair over proteinized and then it makes it more prone to breaking."