It's often just genetics. Sorry! Everyone in my family has the most amazingly puffy eyes with enormous bags underneath. I look at photos of my great-grandparents and there they are: the family heritage in the best of eye bags. Oh well. Allergies can certainly make them more prominent, as I found out when I suddenly became allergic to my dog sleeping in the room at night (so I take benedryl nightly--it may not be primal, but that's life).