In my opinion, Water Fasting is extremely dangerous, there are far more ways to lose weight than to go on a water fast. I have done Water Fast in the past and what people do not realize is when the only thing you are taking in as water you are washing out all the electrolytes and salts in your body. I am a man that used to weigh 300 lbs in 2005, I started studying around 2002, but by 2006 I had lost over a hundred lb and to this day I think I weigh 188 and I have maintained this way which is the most important part once you lose it is to keep it off. What size start creeping up to 200 lb I know that it's time to start cutting back. But getting to your point about losing weight, the average person will maintain their weight by consuming 2500 calories a day, if your small frame and small build I would reduce that down to about 2,000 calories a day. That will make you maintain the weight you are at unless you are grossly overweight. After all the years of studying and practicing I believe that the calorie diet cannot be defeated. The good thing about the calorie diet is you can actually eat anything you want as long as you stay at 1200 calories. Now the 1,200 calories also includes the calories that you drink and most people will neglect this part. But whether it's solid food or liquid drink calories are calories. So the further you drop under 1200 calories the faster you will lose weight. What a lot of people do not understand is the sodium, and sodium is one of the biggest downfalls of a Dieter, because what happens is the person literally is almost starving their self but if they don't take into consideration disodium salt they are consuming, it will really mess them up as they go to the scales because they knew they ate very little for the last week and all the sudden they are holding an extra 5 lb. The reason you gain 5 lbs overnight is because of the sodium is causing you to hold water so if you just stick with the diet stay away from the salt and keep drinking distilled water you will be amazed at your weight loss progress. There's a lot to say about sodium intake on a diet. The great thing about this diet is you can literally eat anything you want as long as you count the calories and stay away from the salt. Salt and Sugar both will make you retain water and most people never talk about this, the reason salt will make you hold water is because it is toxic to the human body and so the body tries to dilute down the salt with the water and that's why you retain it until the danger has subsided, on the other side with Sugar it will kick your insulin levels up and the extra insulin will calls Danger lights to come on in the body and so the body will flood the system with water to dilute the extra insulin. I hope you the best on your diet.