Bling,
I wouldn't call Juicefasting or Juicefeasting (as some people call it) a starvation diet: it is more of a "reducing diet" with weight loss and health benefits that accrue because of it. Fresh organic juices are saturated with natures nutrition.
Paul Bragg did add the items you mentioned, such as Apple Cider Vinegar to dissolve mucus, but for the purists this was again a reducing diet.
Any form of liquid nutrition though is better absorbed by the body as it requires the minimum of digestion: that is why fruit is considered to be easily digested because it is mostly water and considered by most to be pre-digested. So basically, more benefits accrue with the least amount of nutrition, and therefore Water Fasting is considered by many to be the "ultimate" with zero nutrition. This forces the body into Ketosis which results in the maximum healing and cleansing.