Is Juice Fasting Healthy?

Recently, on netflix, I watched the documentary "Fat, Sick, and Nearly Dead" which follows a man during a two month juice fast.  He was medically supervised and his blood work throughout showed no reason to be concerned.  The results on his body were amazing.   I tried to calculate his caloric intake and figured it to be about 2000 calories per day.  This is sufficient to keep the body going and to lose weight.  In the documentary, he did indeed lose tons of weight and claimed to be feeling great.  It even "cured" some of his other health ailments.  While the results were inspiring, I couldn't help but wonder if it's really healthy.  Juice fast diets typically use a wide range of vegetables and fruits.  If done properly,  you'd be getting plenty of vitamins and calories from carbohydrates, but where are the fats and proteins in this diet that are necessary for the body to function?    At first glance, this juice fast diet seems to be too trendy and perhaps even dangerous.

I have spent years going on and off of low carbohydrate diets where most of the "experts" said it was unhealthy.  On or off, my cholesterol levels and blood pressure have been fine.  The low carb diet worked well for me and I felt good.  So, why should I be so quick to just toss aside the idea of a juice fast simply because it doesn't fit into my current reality framework.  I think it's worth investigating.  And, so for the last week, I have been reading about juice fasts.  I'm the kind of guy who has to study something and understand it before I jump in.  

In a nutshell, here is what I have found:   Most websites and books touting the benefits of juice fasting seem to be tied to money making schemes where they try to sell you juicers or guides.  Almost all claim that the diet is good for detox but can never really pinpoint exactly what these so-called toxins are.  Supposedly, you feel sick a few days into the diet and then as the toxins leave your body you start feeling much better than you did even before the fast.  I can find no scientific studies to explain what these toxins are nor if they really are flushed out of your body.  Granted, many vegetables do contain antioxidants which could be helpful.  However, you can have these vegetables in your diet with or without fasting.  And, I haven't quite figured out how to make a juice with significant healthy fats and proteins.  I seriously doubt that I could juice an avocado or nuts without creating an oily mess.  Furthermore, juicing implies a lack of fiber.  Just having liquids in your diet is touted to cleans the colon and digestive track.  I'm concerned that little fiber might not be healthy either.  With all of this said, I really can find no specific documented unhealthy side effects to juice fasting.  While it may not be healthy per-se, I can't prove that it is un-healthy either.  Beneficial or not, it seems that most people's bodies can handle it okay.  

Partly because I can't prove or disprove the effectiveness of "juicing" I am considering trying a 10 day juice fast.  There is no way that I would attempt to go two months like the guy in the documentary.  I still don't know that it would be safe for prolonged periods of time.  

My expectations would be:

1. Gain better control over my hunger and cravings.
2. I'm not convinced about detox but expect to feel woozy for the first few days until glycogen stores in my liver are depleted due to reduced caloric intake.
3. Changes to the way I feel.  I suspect that I will feel rough at the beginning but that I may begin feeling good simply due to having more vitamins that were previously missing in my diet.  
4. "Shrink" my stomach.  I suspect that for a short while after, less food will feel more filling.
5. A good springboard for giving up caffeine.  If I do this fast, I plan on not allowing caffeinated beverages back into my diet.

Before I decide if to start, I'll need to do more research to develop the best recipes to get the proper nutrition mix.  If I can't get enough protein, I probably won't make an attempt.  

If any of my readers know of any good "juice fast" resources, please share by posting comments here.