You would be surprised. :D Yes, it's one of the most beneficial things one can do for his health. It's a next level of detox where the goal is to remove old blockages and waste that we accumulated over the years and decades. Once eliminated, the body can much more easily absorb new nutrients. It's easier than water fasting as you actually consume calories from the juices so the cravings usually disappear after about 3 days. I've posted couple of articles about it recently if you want to read about my experience. Been on it for 22 days but know some who've done it for 4 months or even a full year. I will likely do it again next summer.
If you want to learn more about it, definitely check out John Rose on youtube. He's got tons of videos about "solid food vacation" as he calls it.