Effects of a Vegetable/Fruit Juice Based Diet On The Human Microbiome: Is It Actually Healthy?
Juice based diets are all the rage these days. You can find a lot of discussion and fantastical claims on the internet about their effectiveness as a weight loss tool, as well as their benefits to our overall health. [1], [2], [3]. As a scientist, one is usually skeptical of these claims as a juice based diet does not necessarily confer the balance of nutrients that is more typically recommended for the maintenance of health, and the sources of these claims are not often written from a fact and evidence based perspective. This is not a judgement as to whether or not they are true, but an indicator that perhaps, just maybe, some intrepid scientists may want to dive into this phenomenon more thoroughly.
One part of our bodies that we are coming to find plays a large role in dictating our overall health is our Microbiome. The microbiome is the collection of all bacteria and other microorganisms that live in our digestive tracts. The composition (aka the relative amounts of the different types of these organisms) has been found to change relative to whether or not we are healthy [5] and it is thought that maintaining a healthy microbiome composition aides in maintaining our own health.
In light of all that today lets discuss an article recently published May 19, 2017 in the journal Nature: Scientific Reports titled "Health benefit of vegetable/fruit juice-based diet: Role of microbiome."
The authors in this article decided to investigate the health claims of juice based diets (stating outright that there just hasn't been sufficient scientific evidence to support the claims and anecdotal evidence touted by many). They hypothesized that changes to the microbiome composition (as the types of microorganisms that thrive will be dependent on the particular subset of nutrients which are available for them to live off of) that occur from participating in a juice based diet may cause the health benefits that many claim these diets to have.
To go further into the nutrient argument, fruits and vegetables contain a variety of polyphenolic compounds, which have been observed to have antioxidant, and antimicrobial properties. [8] It is also known that polyphenols aren't absorbed particularly well in our small intestines, meaning that many will pass through into the large intestine, home to the vast majority of the members of our microbiome.[9]
It is possible that the effects these compounds have (especially antimicrobial ones) will result in bigly (LOL) changes (the best changes, everyone is saying it, the smartest of people...)
...to the types of bacteria that are thriving there, and that changed microbiome composition will lead to downstream health effects.
So What Did They Do?
The researchers put people on a very brief juice diet of three days (which doesn't seem like much but hey that was the study),
6 bottles daily of mixtures of greens, roots, citrus, lemon, cayenne and vanilla almond
which was followed then by a more traditional 14 day diet. They then investigated whether or not the juice diet caused changes to the composition of the participants microbiomes, as well as looked at more traditional health indicators like body weight.
Speaking of body weight... what happened from the juice diet?
Their results are depicted in the plot above. After the juice only portion of the diet the participants were seen, on average, to have lost about 1.7 ± 1.2 kg (which doesn't at all look like the error bars in the plot...) and after returning to their normal diet were seen to have kept some of the weight off, remaining down 0.91 ± 0.9 kg (or 0.9 plus or minus all of it?... again that error bar doesn't look like it accounts for as much as the text reports). So it appears that the participants lost some weight and kept it off as a result of the brief juice diet (or they didn't... the error is huge.. but I will report what the authors discuss!).
Did The Juice Diet Change The Microbiome Composition?
Here we are looking at the authors reported determination of the composition of the bacteria residing in the participants bodies (they determine this by looking at the peoples poop... there I said it! And then sequencing the bacteria's ribosomal 16S rRNA segment to identify what was there). What we can see is that after the completion of the juice only portion of the diet, the microbiome composition did change.. and in a pretty significant way! The participants showed a statistically significant increase in the amount of bacteroidetes and cyanobacteria and decrease of firmicutes.
The authors listed some more specific information with the participants showing a massive increase over baseline amounts of Halospirulina (a reported 1467% increase) a cyanobacteria and drastic reduction in Streptococcus (showing only 8% of what was there prior to the juice diet) one of the firmicutes.
What Do The Authors Conclude?
- Their study illustrated that a juice diet resulted in a statistically significant reduction in body weight, that was kept off up to 14 days after resuming a normal diet.
- The relative proportion of Bacteroidetes has been associated with a decrease in body weight, the authors observed that the juice diet drastically increased the Bacteroidetes population, which is consistent with prior findings. The inverse is true for Fermicutes, which are correlated with increased body weight, also consistent with their findings here. Less Fermicutes, and lower body weight.
In summary the 3-day vegetable/fruit juice-based diet induced significant changes in the intestinal microbiota which were associated with weight loss. Further mechanistic studies are required to confirm that changes in the microbiota are directly linked to weight loss.
So what they showed here is that a microbiome composition change resulted from the juice diet, and the juice diet did result in lower weight.
- To limit the length of this post I did not discuss a few of the other of the authors findings, including that the juice diet resulted in an increase in blood and urine nitric oxide levels (which is an indicator of vasodilation and may point to beneficial effects for heart health) as well as the participants showing reduced amounts of lipid oxidation (as measured by urine malondialdehyde concentrations, indicating that the juice diet did have an increased amount of antioxidant compounds which did have a detectable effect on the body).
My Personal Thoughts?
It's clear that a lot more study should be performed on this, but it certainly does look like a juice diet is a pretty healthy option (and seemingly effective). That said I remain skeptical of many of the outlandish claims that you can find out there.
Still... maybe...
Sources
- http://juicing-for-health.com/benefits-of-juice-fast
- http://www.huffingtonpost.com/woodson-merrell-md/juice-cleanses_b_4549641.html
- http://www.shape.com/lifestyle/mind-and-body/your-body-juice-cleanse
- https://en.wikipedia.org/wiki/Microbiota
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4290017/
- https://www.nature.com/articles/s41598-017-02200-6
- https://en.wikipedia.org/wiki/Polyphenol
- http://www.mdpi.com/2072-6643/6/12/6020
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2871118/
All Non Cited Images Are From Pixabay.com And Are Available Under Creative Commons Licenses
Any Gifs Are From Giphy.com and Are Also Available for Use Under Creative Commons Licences
Images from figures in Nature: Scientific Reports articles are available for reuse under a Creative Commons license (all figures will be appropriately attributed and linked back to the article of reference).
If you like this work, please consider giving me a follow: @justtryme90. I am here to help spread scientific knowledge and break down primary publications in such a way so as to cut through the jargon and provide you the main conclusions in short (well compared to the original articles at least!) and easy to read posts.
Excellent work dear friend @ justtryme90 the games beyond that are very good for physical balance, it is very healthy to prevent diseases like green juice of spinach and spinach, red beet juice and the special juice of carrot, Thank you very much, my dear friend, for this excellent job.
Thank you for reading and for your kind comment. I am quite glad you enjoyed the post!
If this non-scientist (me) is not mistaken, a fruit and veggie juice diet would have a lot of fructose. This contrasts with other diets that may be higher in other forms of sugar, like glucose. It seems quite possible that some intestinal flora would do a better job metabolizing one rather than the other. Also, juice does not have as much fiber as whole foods, so that sugar might be absorbed a lot more quickly. Might have a strong impact on blood sugar.
You are correct. Sugar composition of what was consumed may indeed also play a role and that should be considered more highly in follow up studies. That said, sugars would be absorbed pretty well in the small intestine, especially ones like fructose which our bodies LOVE (for better or for worse... probably for worse), so much of it might not make it to the large intestinal microbiome at least. Still good points with regards to blood sugar as well. One thing to keep in mind was that this diet was still caloric restrictive (only ~1300 calories/day during the juice diet phase) so the participants would likely be in a state where blood glucose was fairly low.
I am in line with your interpretation. important to note is that microbiota can change on a regular basis based on what you eat (which this study highlighted). however, they didnt consider this in the context of resident microbiota. and another important aspect that we must never forget, not directly related to the study, is that evidence based is not necessarily science based. more simply put, there's a lot of non-scientific evidence out there. :)
Well said and I agree with all points you made. Not that, that comes as any surprise to you @cristi. Thanks for reading and your input.
I'm looking forward to more similar post from you! whenever I have time for reading on steemit, they are high on my priority list.
there's nothing like learning from experience.
nice info....
Thanks for reading! Most appreciated.
wow I'm really impressed you know your stuff you have a new follower :) I enjoyed this post. Thank you.
Thank you very much! I try my best!
I'm into health and fitness too! Well you do a great job! Keep them coming :)
I write about a wide variety of biology and chemistry related topics. I do love health and fitness related materials, but I try to keep some variety in what I write about! I don't want people to get bored! :D
Very true about keeping some variety! I hope to be half as good of a writer as you one day.
Oh gosh, I appreciate the complement. However I don't think my writing is all that great (YET! I am practicing and slowly improving) I suspect you could show me a thing or two pretty quickly!
Ha! Lets compromise, we can show and support each other every time we post something :))
If you post science related materials, you will certainly get my support. Pretty much all of my voting power is donated to the @steemstem project, which only votes on STEM posts. (its why if you look at my wallet my steem power has a negative number under it)
Following you now by the way, I just realized that you werent on my list.
Oh, thank you very much man. Most appreciated :)
Very well written. I especially love the fact that you remain unbiased and simply break down the finding of the study in simple to understand terms. Ironically, some of us at the office are starting to do our own research into diet and juice cleanses. Well timed article.
I have my biases, but I tried to make clear what they are, and openly state when something was my opinion. Nothing is worse then someone presenting opinion as scientific fact. The data is what it is, and so I like to explain it and let others form their own opinions.
Thank you for reading and commenting. Truly pleased you enjoyed this post.
True. I certainly hope that more studies will be conducted. There definitely is an abundant amount of anecdotal evidence in regards to the effects of a juice diet.
I suspect that there will be more. Especially if studies like this one get attention.
Interesting article. Too much fruit very bad for the teeth though (high levels of acidity). ...But I guess it's like everything else, do in moderation.
Yes I'll have to dig out my blender again!!
Thank you for reading. :)
I drink them every day
I feel much better then before.
For this diet it seems like you would have to have days where you only drink juice. At least basing on this research it's about limiting what nutrients are able to reach the gut bacteria.
Thank you for reading.