But no matter how nutritionally choice the bitter roughage was proven to be, and how many recipes we added to our Bookmarks, we were keeping a secret: Very few of us were actually living that eat-kale-every-day lifestyle. The same applies to the mountains of research supporting retinol 's status as one of the most super-powered ingredients in your skin-care routine for achieving smooth, evenly-toned, acne- and line-free skin — and the fact that most of us could benefit from using it way more than we do now.