I'll be curious to know the answer too. I also have the same thing and I sleep more than enough. I just figured it was age since I'm nearing 30. Yikes...30 just hit me I have 2 years left...nm sorry about the threadjack for a moment....
Anyway, I use concealer, but it never really works to hide the circles. I've always taken great care of my face with name brand cleaners, masks, toners, etc. and still have the black bags.
Great question and I'll be curious to see any solutions.