The Green Smoothie Diet and Juice Fasting Craze! Healthy or Hype?

Burn The Fat Blog: Vegetable juice fasting and green smoothie diets have exploded in popularity in the past few years. Everyone from authors to supplement companies to juicer machine companies to personal trainers (who want something else to sell) are cashing in on this hot nutrition craze. But does it live up to the hype? And is it really healthy? In today’s post, Tom Venuto answers these – and many other questions about “the green smoothie diet” and the juice fasting craze…

Q: Dear Tom, I was browsing through NetFlix looking for inspirational weight loss stories, and I ran across a documentary called “Fat, Sick and Nearly Dead,” which apparently has been out a few years, but is still very popular. I admit, I got totally sucked in. But I also heard the movie was heavily advertised and promoted on TV, and that made me skeptical as well (we all know about nutrition fads and talk shows lately). So I spent a lot of time surfing for an honest review about whether this “juice fasting diet” was really healthy.

The show’s star and host, Joe Cross, mentions that fasting has been used throughout history as a method for body healing and claims that the cessation of digesting solid food saves the body energy which it can then use to heal and repair the body.

One problem, it seems, is a lack of protein. I also have issues with the fiber being removed from the fruits and veggies. And I didn’t see Joe hitting the weights or performing any sort of cardio until after his juice fasting journey, so it didn’t seem to be about fitness at all, just dieting. I know the importance of training from Burn the Fat, Feed the Muscle (BFFM). In fact, I thought his body composition looked a bit “soft” after his 60-day diet was all said and done.

Despite those reservations, I’ll be honest and direct here: I haven’t been successful yet in my efforts to get healthier and leaner and the idea of having a “program” which is that simple – just drink juiced greens and vegetables four times a day – even though extreme, is appealing to me.

I haven’t seen anything really negative about this documentary or about green juice fasting, and like you’ve always told us to do, I did my due diligence searching for evidence and criticism on credible websites before deciding. Maybe I didn’t dig deep enough, but anyway, I went ahead and bought a juicer and a juice recipe book. I thought I would try it for 10 days, as Joe isn’t recommending everyone do what he did, but to try it for 10 days, which he calls a “reboot.” Do you have experience with this? What do you think Tom?

A: Let me give you my short answer, in two parts first, then read on if you want my complete explanation:

1. JUICING, as a way of eating more vegetables and fruits – green and all other colors? Absolutely! I’m all for eating more fruits and vegetables, whether you eat them whole or you juice them with a juicer or turn them into a smoothie with a blender (particularly if you keep some pulp and fiber). If you like the taste of juiced vegetables and you find drinking them easier than eating them as whole foods, then go for it! Personally I don’t care for veggie shakes, but I do drink protein shakes with fruits like bananas and strawberries.

2. JUICE FASTING, where you eat (drink) nothing but juice for a week to 10 days (or god forbid 60 days?) I don’t recommend it. It’s an extreme crash diet, disguised under the halo of “healthy eating.” In some incarnations, juicing comes with all kinds of bogus health claims, ranging from curing disease to (more typically) cleansing and detoxification – both meaningless words, without scientific basis.

I watched the documentary when it first came out, but I haven’t read Joe’s books, or anyone else’s juicing or green drink books. Therefore, beyond what was discussed in that one film, I can’t comment or critique specifically without knowing exactly what is being recommended (especially calorie level, macronutrients, duration of the plan or whether drinks are simply incorporated as a part of your existing meal plan or they are consumed instead of whole food).

However, I do want to take this opportunity to discuss both the juice fasting that Joe talked about in the documentary as well as the whole green drink craze that’s going on right now in general.

Beyond the juice fast alone, green drinks (aka green smoothies) have exploded in popularity for both health and weight loss. Green smoothie spokespeople are all over the talk show circuit now (TV shows LOVE demonstration and nothing “demonstrates” on screen better than a huge pile of vegetables and a nice noisy juicer machine, ending with the host taking a sip, smacking her lips and saying, “Hmmmm.. not bad!” The best seller charts are full of green drink diet books and cookbooks. Everyone from authors to supplement companies to juicing machine companies to trainers (who want something else to sell) are cashing in on what is right now the hottest nutrition trend.

In the Fat, Sick and Nearly Dead movie, Australian Joe Cross says he has come to America, but he’s not going to eat any of our food (junk fast food). All he’s going to eat for two months as he road trips across the country is juiced vegetables and fruits. With little or no whole food, he calls it “juice fasting” (even though it’s not total fasting). On the road, he spreads his message with anyone who will listen.

Joe started tipping the scales at over 310 pounds, and his weight loss was a big part of the story. However, he talks (admirably) about the importance of eating for health as much, if not more so than eating for weight loss because he had some major health problems before he began his trek. When it was all over, Joe was healthy and had lost 80 pounds.

Some of the other “green smoothie diets” on the market are making weight loss claims to the tune of 15 pounds in 10 days. The big question is, 15 pounds of what? How much is muscle loss? How much is water weight that’s just coming back at the end of the 10 days? How much of the fat loss is sustainable fat loss?

Joe admits, in his own words (from his website), that the way he did it for 60 days was “extreme.” He recommends other people do it for a shorter period of time. Typical juice fasting programs run only 7 to 10 days. That’s 7 to 10 days of essentially starvation level calories. 10 days to drop a ton of body weight: It’s a classic quick fix diet.

I understand the premise of “kickstart programs” or what Joe calls a “reboot.” Usually, you freely acknowledge that you’re not going to do this forever; you’re simply going to initiate the diet with a bang, using some kind of extreme restriction to get you off and running fast. This is not a new idea, nor is it exclusive to the plant-based crowd. For example, in the Atkins diet, a low-carb, high-fat, animal-protein-based plan, there is an “induction” phase with carb restriction much more extreme than during the rest of the diet.

There might be a potential positive aspect of approaches like these: A large weight loss in the first week is motivating for a lot of people. Contrary to popular belief, there is some good research demonstrating that people who lose weight quickly at first are not always at greater risk for re-gaining it – it depends on the person. Unfortunately, the odds are not in your favor, and there are negatives to extreme first week approaches as well.

In the film, Joe comes across as likeable, believable, enthusiastic, and sincere. His message has clearly inspired a lot of people. The documentary was well done, well received, reviewed with high marks and had very few critics. I mean really, what could be wrong with eating more green veggies especially for the sake of health? Nothing. Unless that’s the only thing you eat, you don’t promote exercise at the same time, you fail to acknowledge weight loss versus fat loss and you don’t emphasize lifestyle change right from day one.

As nutrition research has advanced, it has become pretty clear that a partial day or single day of fasting – juice fasting or even total fasting – isn’t going to cause any harm to muscle or metabolism. But the further you go beyond a day or two without protein or adequate calories, the more muscle-wasting and metabolism-damaging it becomes. Combine low protein with no weight training and you have the perfect recipe for muscle loss. But even if you wanted to train, without adequate energy intake, physical capacity is diminished and most people couldn’t train hard if they tried.

The biggest problem, in my view, is when unsubstantiated health claims are made. Where many juice fasting or green drink diets start off with good intentions but deteriorate rapidly into pseudoscience is when they start talking about “detox” and “cleansing.” Any time I hear these claims, the author or promoter of the program instantly loses credibility and I write them off as a serious resource, or even file them in the quack category.

No thanks to celebrity endorsements and mainstream publicity for “detox” and “cleansing” diets, many who have eaten junk food their whole lives have been convinced that they are “toxic.” As a result, they think they need some super-food juice drink, esoteric supplement or bizarre ritual like flushing out their colon to cleanse themselves. This is one of the biggest lies in diet industry.

What these people really need to do is to cleanse their refrigerators of junk food – for good – for life – instead of trying quick fixes for problems that resulted from many years of neglect. You have a liver, kidneys and immune system that takes care of the rest.

Eating vegetables and juicing vegetables is healthy. Juice fasting, for all the health claims that are made, may not be as healthy as it appears, nor does it support an athletic lifestyle. Fruits and vegetables are fiber-rich and micro-nutrient dense, but by themselves, they don’t provide all the nutrition or energy your body requires. If you ate only vegetables or even only vegetables plus fruits, your calories would likely fall too low to provide optimal amounts of macronutrients or micronutrients (500 to 800 calories a day is not uncommon).

Joe recommended rotating drinks made from different vegetables, which is a smart way to improve the variety of micronutrition, but what about the macronutrition? What about the protein (essential amino acids) and fat (essential fatty acids)? You could buy the pea and rice protein powder he’s selling, but on a juice fast, you’re going to fall short on quality protein.

I read one critical review that said Fat, Sick and Nearly Dead was “The most cleverly disguised infomercial of all time.” Surely there were underlying promotional motives. But let’s assume Joe and his film’s producers had noble intentions and they weren’t consciously pushing any kind of gimmick or scam. I think that’s fair to say, and that’s commendable. Joe is likeable guy (add the Aussie accent and he comes across as downright charming). But nice guy or not, it still doesn’t make a prolonged juice fast anything more than an extreme crash diet. It’s also just one man’s testimonial.

Like The Biggest Loser and other dramatized stories, one person’s success can be inspiring. If you can pull some inspiration from “extreme” stories like these, I think that’s a check mark in the plus column, but it doesn’t mean you should adopt their methods. Maybe borrow an idea or two, but mainly use it as a catalyst to be more inspired to get healthy and follow your own plan (hopefully one that involves a lifestyle including exercise, fitness and muscle).

Long term weight control takes sustainable lifestyle change and new habits, not drastic measures like starving, fasting or drinking juice shakes all day long. Everyone loses weight on starvation diets in the beginning. The problem is, quick fix diets -by definition – are unsustainable, they don’t emphasize body composition, and they don’t teach you lifestyle or real, lasting health habits. Many of them are downright miserable to follow because of the food restrictions imposed and the hunger they produce.

Ironically, liquids are usually far less satiating (filling) than whole foods, especially if the pulp and fiber is removed. Should one wish to add juice drinks into a balanced diet including whole foods with adequate calories, macro and micro nutrition, there’s nothing wrong with that. But to promote nothing but juice drinks or a disproportionate amounts of drinks compared to whole foods is unwise.

A vegan / all-plant diet can be pulled off successfully in a healthy way by people who have that preference. However, it’s less likely to provide optimal nutrition if it’s so restrictive that you drop all natural starches, whole grains and legumes (where much of the plant protein comes from), or nuts and seeds (where essential fats come from).

Here’s my advice: Yes! Absolutely eat more fruits and vegetables! That’s one rule of good nutrition you almost never go wrong with, and yet it’s the one place where most people still fall short. Eat your fruits and veggies whole, and if you want to, use a blender or juicer and drink some of them, if you enjoy it. If you don’t like the taste or texture of juiced vegetable drinks, then don’t drink them – just eat your veggies whole.

Green drinks have never appealed to me. I think a lot of them are actually kind of gross (tastes like grass!), so I prefer to eat food. In a scene from Fat, Sick and Nearly Dead, Joe has recruited a lady with health problems to follow along with him. She juices up some green foods, takes her first sip, cringes and says, “Oh that’s nasty.” I bet if you got a good cookbook, you could find some drinks you really like, especially if they have fruit because then you have some natural sweetness. But my guess is that a lot of people drink these not because they enjoy the taste, but because it’s trendy and being seen drinking a green drink makes you feel virtuous.

Personally, I like big salads, I love healthy stir-fry’s, I load healthy veggies into my omelets in the morning and I do have a good-sized list of favorite vegetables I eat alongside my lean proteins every day. I get plenty of veggies from whole food every day and so can you, if you choose.

One last thing. Juice fasting and all kinds of smoothie drinks are one of the biggest diet crazes right now. But juicing fruits and veggies isn’t a new idea.

I wonder how many people still remember Jack LaLanne? He was in his prime before I was born, but I’ve always been a fan of his lifetime of work.

Lalanne emphasized exercise and nutrition as a royal pair – like king and queen – including training for muscle and eating for muscle, the natural way. LaLanne was the “true original” and he left behind a legacy of health and strength.

Jack promoted juicing since he was a teenager way back in the early part of the last century. But Jack’s way was quite different from today’s crop of quick fix diets. For Jack, it was a swap: Juicing was his way out of being a sugarholic when he was a kid, and he recommended juiced fruits and vegetables as a replacement for junk food and soda.

I own his books – the new ones and some of his old ones – and have watched many of his classic black and white TV show reruns on video.

I don’t recall reading anything about him promoting juicing as a rapid weight loss tool. He said he was passionate about eating more fruits and vegetables, including juicing them, for health. In his book, Live Young Forever, on page 216 he wrote: “This section contains some juicing tips, but make sure to EAT lots of fruits and vegetables too!

I do believe Jack stopped eating meat later in his life or reduced it greatly, so he did advocate getting a large portion of calories from plant sources. But he also recognized the importance of protein and said he kept eating fish and eggs.

In his last book, written not long before he passed away at a far-too-young-for-him age 96, he also suggested sugar free yogurts as a smoothie ingredient, so he was never anti-dairy or anti-animal protein. He also included yams, brown rice, oats and whole grains. LaLanne’s approach was a lot more balanced and a lot closer to what we recommend in our health and fitness community than today’s juice-only crash diets.

In Burn the Fat, Feed the Muscle, a juiced drink would simply be an exchange / swap for a whole fruit or vegetable. So juicing or alternately, having protein smoothies, which may or may not also have fruits or veggies in them, easily fits into the Burn the Fat, Feed the Muscle program.

On the other hand, prolonged fasting, or extremely low calorie diets of any kind, will never be tactics I recommend or implement into the Burn the Fat, Feed the Muscle program, not even as a first week kickstart. You DO NOT have to eat nothing but veggies (or on the flipside, nothing but protein) to get off to a great start. You DO NOT need any quick fix tactics.

If you want to get off to a fast start, simply take a little more aggressive calorie deficit while still eating adequate protein and a variety of whole foods, (including lots of vegetables), mind your compliance, and of course, TRAIN HARD! That’s the balanced, sustainable and healthy approach I promote today in my program, Burn the Fat, Feed the Muscle.