I actually bought this to make my bed-in-a-box *harder* because mine was just too soft and I felt like I was sinking further and further into it, which caused back problems. I'm not even a heavy person...just bad mattress I guess, but I don't have the money for a new one. Anyways, it's been about a week with this pad and it has REALLY helped! It keeps me from sinking into the bed and has really helped me sleep better. Yay!