When I fist heard about niacinamide, I thought yes I want all these benefits sooo i decided to add it in my routine and use this one. Let’s say that I wasn’t seing any results so I stopped using it and then it hit me. During the 3 months I used this serum, I didn’t have any of those nasty and painful pre period pimples. So I started usingit again and now I love it (and niacinamide in general). It’s lightweight and non sticky (the one from ordinary and inkey list are pretty thick and sticky).