Can you explain about this fast that you're doing? In the 3rd week are you eating nothing? When you starve yourself you may not even lose weight because your body goes into starvation mode and stores fat. So if your main goal is to lose weight it would be better if you did the Lemonade Diet (Master Cleanse) It's cleansing and people do lose weight on it. The key, of course, to keeping the weight off is to eat smaller portions of good, healthy food....and drink lots of water.