Is the weight I gain water weight? I am on day 13 of a fast that started out water, but on the 7th day I added a yogurt with 1/2 spoon honey to repopulate my intestinal flora, and have kept strictly to that. The rest water. I am SO thirsty. I decided to have a bitter black cup of coffee this morning to see if it'll kick start my metabolism a bit (surely it will help with water retention, too).