I had a really tough time on my second day (I am also on my third MC) - I felt like I was starving! But it did pass. Now I don't feel hungry at all (day 7). Keep going! Drink more of the drink. I don't even keep track of how much I am drinking during the first few days because I feel it is more important to stay on the Master-Cleanse and get over the "feeling hungry" hump than it is to measure and stay within a certain number of glasses.