Squeezing every last drop out of a silly trend

 

To this day my friends know me as the one whose mom never kept juice in the house. “It’s just empty calories,” my mom would say. At the time, I had no idea what “empty calories” meant, but I did know that my mother was an infinite fountain of knowledge who was not to be questioned. Thus, mother instilled in me from a very young age an important lesson: juice= bad.

Or so I thought.

Then sometime in the second decade of the 21^st century, all of these fancy cold-pressed juice bars start popping up, touting the health benefits of apple-carrot-lime-pear-kale juice. Ads on my Facebook feed starting coming up, offering week-long juice cleanses that promised to rejuvenate my soul. I mean, who doesn’t want a rejuvenated soul?

The juice-deprived child in me hoped that this fad had any glimpse of legitimacy to back it up. But white-walled juice bars and tempting Facebook ads aside, the verdict is in:

Juice = still unhealthy (and thank god, or I’d have to blame my mother for the injustice of such a juiceless childhood).

Read on if you wish, or you can just take my word for it and stick to drinking water and eating your apples whole.

Cold-pressed,what?

When my mom said that juice is made up of empty calories, she meant that juice is full of sugars that provide you with energy, but lacks a lot of the other good stuff found in fruits and vegetables. That’s because when we squeeze the liquid out of a fruit or vegetable many of the molecules are exposed to the air. That’s not great because oxygen exposure speeds up degradation and depletes the fresh produce of many of its beneficial nutrients.

Even the freshest and best pressed juice will have less nutrients, less fibre, and will cost more than getting the same nutritional profile from whole foods.

What the heck is a nutrient, you ask? Well, technically, a nutrient is a substance that provides nourishment to your body. Sugars, proteins, and fats are the nutrients we eat in the largest quantities—they provide our cells with the fuel they need to function, grow, and repair.

But there are also other nutrients, called micronutrients. Micronutrients include vitamins, minerals, and (the less-essential-but-still-good-for-you) polyphenols and phytochemicals. They don’t provide energy, but they are necessary for our bodies to function well.

Juice bars have found a way to retain the nutrients that would otherwise be destroyed in the juice-making process by the cold-pressing their juices.

So yes, these fancy new juice places that charge $9.00 for their elixirs most likely have a higher nutrient content than juice that you could buy in a Tetrapak at the grocery store. However, even the freshest and best pressed juice will have less nutrients, less fibre, and will cost more than getting the same nutritional profile from whole foods. It’s true that in this way you can get the same number of nutrients with fewer calories, which is why some people think drinking juice is a healthy way to lose weight. But you can lose weight while eating whole foods you eat and still get all of your daily nutrients! Plus, eating whole foods will make you feel fuller and more satisfied than juice ever could.

Fibreless Markings

The biggest pitfall of juice is its lack of fibre. Whole fruits and vegetables are full of fibre, but most of that gets left behind in the juicing process. Not only does fibre help our digestion move along and clean out the debris in our gut, but it plays a big role in making us feel full and satisfied.

Dietary fibre consists of all of the carbohydrates that we cannot break down into small enough pieces to absorb into our bloodstream. But just because it doesn’t give us energy mean we don’t want it! I like to think of fibre as the tour guide of our digestive process: it keeps our food moving at a good pace, holds everything together so that it’s not coming out the other side in a disorganized mess (if you know what I mean) and it feeds the important bacteria in our gut. (Okay, I’m not sure how what last one works into my analogy—maybe it’s like the tour guide that talks to all the locals along the way?)

Whole fruits and vegetables get a great tour-guide-to visitor ratio on their exploration of our digestive tract.  What I mean is there is a ton of fibre compared to the energy-providing sugars, fats and proteins. Since fibre is stays along for the entire digestive ride, it also adds tons of volume to the food we eat without significantly increasing the caloric intake.

The volume of food we eat has a lot to do with how full we feel. When our stomach walls start to get stretched, it lets our brain know that there is a backup to get to the next stage of the tour. Our brain, always worried about going over capacity, decides it’s satisfied with the number of visitors for now, and provides us with a feeling of fullness. When we get all of our calories from juice, which doesn’t have nearly as many tour guides to take up space in our stomach, our brain never gets the message that we’re full. So, even if you drink enough calories to provide enough energy for the day, your brain doesn’t get the memo, and you hungry and unsatisfied (not to mention clogged up).

Juice cleansing: a culture

Somehow, juice cleanses have become a popular fad. I guess there is an aesthetic allure to these cleanses. For three days to a week, you drink bright coloured juices with exotic fruit and vegetable combinations in sleek bottles. PLUS you are promised to feel more energized, improve your gut health, and curb your sugar cravings. Sounds perfect, in principle.

In practice, however, there is approximately zero science to back up any of these claims. In my opinion, doing a juice cleanse is just going to make you hungry, grumpy, and broke.

Is juice science all a conspiracy?

While doing my research, I found a blog post titled “The Science Behind the Benefits of Doing a Juice Cleanse”. I was so excited that there may be some science to back up this whole juicing thing! Until I read it.

The blog post cited one study, supposedly done by a research group at the University of California Los Angeles (UCLA). It lists the findings that were allegedly reported in the study, including weight loss and energy boosting. But when I clicked on the hyperlink to the UCLA study, it redirected me to a website that sold cold-pressed juices. Hmmm.

Next, I called the juice company, and it turns out that they commissioned the researchers at UCLA to conduct a study on the nutritional profile of their juice. The juicery website claims that the publication was reported at a nutritional conference, but I could not find this article anywhere.

A three-day cleanse and its health benefits?

In my search for this elusive study, I did end up finding one paper by a research group at UCLA on the that effects of doing a juice cleanse on human health .(It’s tempting to think that this was the article cited in the aforementioned blog, but the blog was posted three months before this study was published.) The study had 20 participants do a three-day juice cleanse consisting of a variety of vegetable and fruit juices. What they wanted to know was: does a three-day juice cleanse change your microbiota, and does that change in microbiota influence health or weight loss in participants?

Two weeks after the participants finished cleansing, their microbiome looked just like it did before their juicescapade.

Your microbiome is the community of trillions of bacteria living in your gut. There are all different types of bacteria living in there, and some of them are better than others. There is plenty of evidence that the composition of your microbiome may play an important role in your health. In short, the researchers wanted to see if a three-day juice cleanse would give you a better microbiome, and if it did, what positive effects would that change have on your health.

The research found that after the three-day cleanse there was a small change in microbiome of participants. This is not surprising at all, because it is well known that a change in your diet affects the composition of your microbiome. Consuming a diet limited to liquid vegetables and fruits is a pretty drastic change from most people’s regular food intake. But guess what? Two weeks after the participants finished cleansing, their microbiome looked just like it did before their juicescapade.

Two other findings were cited in this article: the participants lost weight. This is also not surprising. The participants were only getting 1300 calories a day—the average adult should be eating around 2200 – 2400 calories per day to remain at a consistent weight. The weight loss wasn’t from drinking juice in particular; it was probably from consuming less calories! On top of that, they gained about 30 percent of that back after only two weeks.

The study also asked participants to complete a general wellbeing survey before and after the cleanse (the paper doesn’t specify what questions are asked on this general well-being survey). People cited the same general wellbeing on the last day of the cleanse as they did on the first. However, two weeks later, they ranked their general wellbeing higher (when their microbiome was back to its pre-cleanse levels!). This is definitely not evidence that juicing increases wellbeing.

So really, the study found that you lose weight and your microbiome might change a bit, but only for two weeks at best. Additionally, these changes were not associated with any positive health effects.

Toxic Marketing

I hear people talk of using juice cleanses to “detoxify” their organs. However, there is no evidence that juice will eliminate toxins from your body, or give your organs a break so that they can eliminate toxins themselves. Fresh Pressed juice may have less harmful chemicals than processed foods, but so does the whole ingredients it is made from. The idea that juice will detoxify you is just another way for juice companies to get your moolla.

Mother knows best

In all my research, I found one measly human trial looking at the effects on juicing. And, and the results benefits it found were slim -to -none! The fact is my mother knew best—juice is less nutritious than whole foods. A diet full of whole foods such as fruits and vegetables and whole grains will provide your body with ample nutrients. No cold-presser required.

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