I have had dark circles under my eyes most of my life but the improved markedly as I started taking Milk Thistle and N-A-C (with vit C & E). These are liver protective, increasing bile production and glutathione.
As I entered my 40's, my undereye area got puffy! That receded with liver flushes. This summer, I want to try a Watermelon kidney cleanse. Perhaps that will help as well.