You may be drinking a lot of water but not retaining enough. That is what I learned when I tried the Water Cure . I always drank quarts of water, but was always thirsty, and especially dry-mouthed at night. When I started mixing 1/4 tsp. of Sea Salt to 1 quart of water and drinking the amount specified by the Water Cure , that was the end of my thirst and nightly dry mouth. I couldn't believe the difference it made. Apparently salt helps the cells retain water better.