I've had edema for a while now. My doctor told me to keep legs above the heart level to reduce it. I've noticed a very large urine volume when I lay down even if I ate a lot of sodium without drinking much water. Usually if I have a lot of salt without much water, my urine output is decreased and concentrated. Lately it;s been very diluted almost clear after sleeping or laying down. Could this be water from my legs even though I've been sleeping on my side? Can this happen laying on your side?