Chances are that your rate of weight loss will slow down some, but, then again, you may be one of the lucky ones who will not experience the metabolic slow down. Long water only fasts can cause the metabolic rate to slow down up to 25%. Juice fasting and Master Cleanse do not have that drastic a slow down, but the rate is usually lowered on long fasts. As you approach your ideal weight (ideal for your body anyway) you may also find the rate of weight loss slows down. If you want to weigh 115 and your body wants to be 130, then those last pounds will be hard to loose.