If I told you that jumping into one of those vibration belt contraptions you used to see on TV after midnight really could help you to manage type 2 diabetes, would you believe me?
I’m not sure I would, but in 2019, doctors and veterinarians from Augusta University’s medical school and Ohio State University’s College of Veterinary medicine did just that.
The scientists claim to have discovered, through a series of experiments, that whole body vibration could help us to reduce harmful inflammation. What’s more, they say, it might even assist in managing blood glucose levels in type 2 diabetics.
Is it too good to be true? Perhaps. Let’s take a look at the evidence to see if these claims make sense. Come with me on this strange journey to understand why these guys say vibrating belly fat, mouse poop and microbiology could one day get us to better blood sugar control.
Good Vibrations?
For reasons I cannot fathom, in the 2010s a team of researchers led by Drs Jack Yu and Babak Baban started looking into whether whole body vibration could be used to prevent obesity and insulin resistance.
Is this an unusual approach to metabolic disorders? Maybe. On the other hand, poorly controlled blood glucose is behind just under half of end-stage kidney disease cases (47%), so we urgently need better ways to help people manage their diabetes. Perhaps it’s time to… ahem… shake things up.
The Georgia/Ohio-based team tested whether vibrating a diabetic mouse at 30 Hz for 20 minutes per day would help it to lose weight. While their efforts to shrink the mice did not pan out, they did, however, discover something intriguing.
The mice seemed to be able to control their blood sugar better after just a week of shaking – and there is, the researchers say, a microbiological explanation for it. Maybe, they propose, an explanation that could translate to a treatment for humans. I am not sure what to think of this, but it’s definitely a story!
All Shook Up
A long time back in the ’80s and ’90s whole body vibration was a ‘thing’. Vibration of our muscles, we were told, could replace exercise. A whole industry grew up around crazy gym and home gym machines that claimed these devices would burn away your fat while you were passively jiggled by a vibration plate or belt. These days there are still some gym bunnies vibing with the belts, but most casual observers wrote it off as a novelty weight loss fad.
Since then, the belts have been (not so) quietly buzzing in the background. That was until 2015. Babak Baban and Jack Yu claimed in the now-defunct Springer Plus journal that if you vibrate a mouse with the mouse equivalent of type 2 diabetes five days a week, for six weeks, it will weigh a tiny amount less than a diabetic mouse that wasn’t vibrated. Apparently, this difference was statistically significant, but to me it looks too small to be meaningful. They don’t show us in the paper what happens long term. I assume the change didn’t get bigger over a longer time, because had it done so, surely they would have shouted it from the roof tops?
They also checked whether whole body vibrations affected the mice’s blood glucose measurements. The vibrating diabetic mice, they said, had 22% lower HbA1c levels compared to non-vibrated diabetic mice. The researchers tested six mice in each condition, and noted that not only were the buzzed mice apparently better able to control their blood glucose, they showed reduced levels of inflammatory markers.
Mouse House Rock
What was going on with these mice and their low HbA1c levels? Is this for real? Well, it looks like it might not be a fluke. In their 2019 article “Whole Body Vibration-Induced Omental Macrophage Polarization and Fecal Microbiome Modification in a Murine Model”, Dr Yu and his colleagues claim that they have now figured out the mechanism by which whole body vibration can lower your blood sugar levels. And it is *not* what I expected.
The link between inflammation and metabolic disorders, including obesity and type 2 diabetes, is a firm one. Traditionally we understand that obesity triggers changes in how our visceral fat behaves. In turn, these changes cause chronic inflammation and insulin resistance that eventually becomes type 2 diabetes. This is a rough and ready simplification of the process because there is a lot of back and forth feedback between the three, but it’s a good approximation for our purposes.
What is clear, is that losing the excess adiposity in our belly that defines obesity can reverse the symptoms of type 2 diabetes and get systemic inflammation under control. Slimming down to a waist measurement of less than 90 cm for men and 80 cm for women makes a huge difference in your ability to produce and use insulin, and reduces the level of inflammation in your whole body.
Inflammation, fat cells and vibration
Metabolic science experts currently think that when the specialized fat cells in our abdomen run out of storage space, we end up with the extra lipids (fat) floating around. This triggers an immune response from the fat cells – our body is trying to get rid of these extra lipids in the same way they react to an infection or a wound. The fat cells release inflammatory molecules – cytokines – to attract white blood cells. One type of white blood cell that comes to help with the clean-up is macrophages. These are the Pacman-like chomping cells that swallow up bacteria, chunks of dead cell and other things we need to dispose of.
These white blood cells can become overwhelmed by the amount of fat that needs to be removed. Eventually they start firing off urgent signals to the rest of your immune system to say something is very wrong, and they need more help.
The result is out of control inflammation, and all the swelling, fibrosis and tissue damage that comes with it. At the same time, the fat cells are so overloaded with stored lipids and inflammatory signals that they can’t respond to insulin’s message to suck up glucose from our blood. This is insulin resistance.
Yu and Baban hypothesized that they could use whole body vibration to help the mice to calm this inflammation and support the fat cells to return to their job of soaking up excess glucose to store it for later. This, they hoped, would lead to lower blood glucose levels and less harm from type 2 diabetes.
That wasn’t quite how it played out. The real story was a bit more complicated and maybe more interesting.
In The Belly of the Beast- What is Abdominal Fat For?
So how would shaking up our belly fat with whole body vibration help our manage type 2 diabetes?
The fat in our abdomen that wraps around our organs has multiple important roles.
Firstly it is structural; it helps us to keep our internal organs from swinging around and getting twisted or damaged, and protects us from impact.
Next, it helps our white blood cells to travel around our intestines and shuttle up and down our insides very quickly. It has stocks of inflammatory signals so it can recruit white blood cells to respond to infection very fast. Our gut needs extra surveillance from our immune cells because it is packed with bacteria – some helpful, some not so helpful, parasites and other pathogens that hitch a ride on our food. The microbes in our gut affect the inflammatory status of our belly fat and it seems like the inflammatory status of our belly fat can affect the types of microbe that can live in our gut.
Visceral fat also stores our fuel long term and short term. Fat cells hold both the fat that we keep in long-term reserve, and glucose in the form of triglycerides that can be quickly released into our blood when our blood glucose levels drop.
Another role that not many people know about is that it can make hormones. Mostly these hormones are related to eating and fuel storage, but belly fat also regulates oestrogen, testosterone and cortisol. This is one of the reasons that metformin is useful for women who have PCOS as well as people with insulin resistance.
Surprisingly, it seems like the effect Yu, Baban and their team saw on inflammation and blood glucose was more related to belly fat’s role in fighting infection than in its role in storing glucose.
Whole Lotta Shakin’ Goin’ On
The team already knew from their last vibrating mouse project that vibrating obese mice makes them lose a little bit of weight and reduces their HbA1c levels by roughly 20% compared to unvibrated mice. Now they were on a mission to find out why.They ruled out the idea that they were using more calories by doing the same test with normal mice. The researchers put each mouse in a plastic shoe box sized cage on a huge vibrating table and set it to jiggle for 20 minutes at 30 Hz five days a week for six weeks. The diabetic and normal mice were buzzed simultaneously – it was a big table. The normal mice didn’t show much effect, but the diabetic mice had lower blood glucose levels than non vibrated diabetic mice. Each set of diabetic mice and normal mice were brothers from the same mouse litter aged eight weeks old.
The normal mice did not lose weight whether they were vibrated or not. The scientists concluded that this meant that mice were not burning more fuel in response to the shaking. The effects of vibration were only obvious in diabetic mice, so there must be something else at play.
Shake Up to Wake Up?
Next they tested whether the blood glucose drop was something to do with inflammation. They jiggled mice again using the same conditions as usual, but this time they collected cell samples from each mouse’s belly fat. Then they used a special technique called flow cytometry to sort and count different types of cells to compare the types of immune cells patrolling the fat around the mice’s intestines.
This is where things start to get interesting.
The regular mice, vibrated or not, had a roughly 40:60 split between pro-inflammatory and anti-inflammatory macrophages.
The non-vibrated diabetic mice, on the other hand, had a roughly 70:30 split. So the diabetic mice predominantly have pro-inflammatory macrophages in their belly fat, while the regular mice have more anti-inflammatory macrophages.
The vibrated diabetic mice had the same macrophage profile as the normal mice – roughly 40:60. The researchers interpreted this as the vibrations returning diabetic mice to the baseline for a relatively healthy lab mouse.
So what this tells us is that diabetic, obese mice usually have almost double the proportion of pro-inflammatory macrophages patrolling their abdominal fat compared to healthy mice.
If you vibrate diabetic, obese mice five times a week (I guess Dr Yu likes his weekends free) for six weeks, 20 minutes at 30 Hz it appears to reduce the proportion of proinflmmatory marcophages from 70% to 40%- just like their healthy brothers.
Microbiome Madness
Next the researchers tested the mice to see whether the vibration had any effect on their gut microbiome. Inflammation is a process that happens in response to infection or injury. It makes sense that the bacteria living in your gut would affect the inflammatory status of white blood cells in your visceral fat next to your intestines – that’s one of its jobs. Could the change in inflammation in the vibrated mice be caused by changes in their microbiome?
The team used advanced DNA sequencing technology to analyse the bacterial populations in each mouse’s poop. After the routine six weeks of shaking, they collected mouse droppings in a test tube, extracted DNA and sequenced any and all bacterial genomes present.
Then they used special statistical software to identify which kinds of bug were present in the poop and to estimate how many different types there were and it what ratios. Normal mice and obese mice had more microbial diversity in their gut after being vibrated but unexpectedly, vibrated diabetic obese mice had slightly less diversity. It was again, like the weight loss, a very small difference, but apparently consistent enough to be statistically significant.
This puzzled the researchers because, typically, the more healthy a person (or mouse) is, the more diverse their gut biome is.
Alistipes: the secret to low blood sugar readings?
The team looked deeper into the microbial DNA signatures, and discovered something intriguing. After six weeks of whole body vibration, the diabetic mice had 17 times more of a special kind of bacteria, Alistipes, than the unvibrated diabetic mice. Not only that but they had a different ratio of microbes to their obese but not diabetic shaken brothers. Obese vibrated mice had more Lactobacilli and Alistipes, and normal vibrated mice had more Bacteroides and Alistipes.
Vibrations seemed to enhance the growth of Lactobacilli, Bacteroides and Alistipes over other kinds of microbe, but the changes in a mouse’s body caused by type 2 diabetes favour Alistipes over other bugs.
Alistipes are microbes that feed on starches and glucose to make short chain fatty acids. The team speculate that these fatty acid-making bugs might be mopping up excess glucose in the intestines before it can get into the mouse’s blood stream. So rather than the vibration changing how fat cells respond to insulin, perhaps the mice with more Alistipes have less glucose in their blood to start off with.
It seems like if you vibrate a type 2 diabetic mouse consistently 5 days a week over 6 weeks, the shaking somehow changes the types of microbes that are happy living in the gut.
How Could This Help Us Manage Type 2 Diabetes?
What does this mean for the link between whole body vibration and managing type 2 diabetes?
The researchers showed in their paper that vibrating obese, type 2 diabetic mice reversed their abdominal fat inflammation and at the same time changed the make up of their intestinal microbiome to favour Alistipes- a type of microbe that eats glucose.
This raises an intriguing possibility, could probiotics to encourage Alistopes be a simple way to help people who struggle to manage their blood glucose levels through diet? This is something humans could try and would be a simple way to solve a tricky problem. I thought this was where the authors were going, but they chose a different interpretation.
Instead the authors suggest that we should vibrate ourselves at a lower frequency or less often and consume Alistipes friendly probiotics as an adjuvant to help enhance the effects of vibration. But do we really need the vibration step?
Putting the pieces together
There are a few possibilities as to how we could understand how their observations can explain how vibration affects blood glucose in type 2 diabetic mice:
- Glucose-guzzling Alistipes fill a niche abandoned by bugs that don’t like the background buzzing. They mop up enough glucose that there is a noticeably lower amount absorbed into the mouse’s blood stream. In turn the lower blood glucose levels put less stress on the visceral fat, lowering inflammation and perhaps allowing the less stressed fat cells to respond to insulin.
- Alistipes take over the gut because of the vibration and for whatever reason are less likely to provoke immune cells in the belly fat wrapped around the intestines. The lower inflammation helps the fat cells to calm down and improves their ability to store glucose.
- A mixture of one and two.
- Vibrating does something to belly fat that changes the inflammatory status of the macrophages. Those macrophages tip the biome balance towards Alistipes, which then mops up some glucose. The lower inflammation state of the belly fat helps the fat cells to absorb more glucose or just helps the body by lowering inflammation in general.
- The vibration affects inflammation directly and entirely independently and also encourages over growth of Alistopes. Together these have an additive effect that helps the mice control their blood glucose better.
The authors of the paper seem to favour option 4.
If you are wondering how you could be sure that the macrophage ratio in the belly fat is directly affecting the bacterial population of the gut, so am I.
They don’t explain their rationale or show any evidence from their own project or other people’s to show that the inflammatory status of macrophages in the omental fat change the composition of the biome. A cursory search of the literature didn’t lead me to any evidence for this either. They say that they are the first to make this specific connection.
Remember, inflammation occurs in response to injury or infection. Isn’t it more likely that over growth of pro-inflammatory bacteria in the gut would make the inflammation in the diabetic mouse’s visceral fat worse than the inflammation encouraging bad bacteria to grow?
If shaking bothers pro-inflammatory bacteria, it follows that losing those nasty bugs should reduce the inflammatory signals that radiate from the gut, in turn reducing pro-inflammatory macrophages in surrounding fat tissue. Not the other way around. The idea that inflammation would encourage pathogenic microbes to grow is counterintuitive.
Nevertheless, the microbiome is constantly surprising us, so who knows? It might not be as strange as it sounds.
The thing is, though, if you are making a claim that nobody has made before, you have to show some supporting evidence for it.
Shakey Science?
Unfortunately, they did not do any experiments to figure out whether there is a link between the inflammatory status of macrophages in the fat surrounding the gut and the presence of Alistopes at all, let alone the direction of the interaction.
Just to start, I would feed the diabetic obese mice Alistipes capsules and Alistipes friendly probiotics, and then measure the level of inflammation in the belly fat, and HbA1c levels, over several weeks. This would test whether the Alistipes are causing the drop in blood glucose, a change in inflammation, both or neither.
Another wrinkle is that, in order to create obese mice that develop type 2 diabetes, they used mice with a genetic mutation that deletes leptin. Leptin is the hormone that controls our appetite. If we don’t have leptin, we over eat. The researchers here don’t test whether leptin affects the composition of our microbiome directly or otherwise. While it’s not a disaster that derails the whole project, it does raise questions over how well any of this would translate into humans. Some metabolic researchers feed normal mice a high fat diet to get them obese enough to develop type 2 diabetes, avoiding this problem. In this scenario they say they fed all the mice the same diet but obviously the leptin negative obese mice ate more than their leptin postive normal sized siblings, otherwise they wouldn’t have become obese.
Finally, each of these experiments only used three mice per condition, twice. So they vibrated three obese, diabetic mice, vibrated three not obese, not diabetic mice and compared them to three obese, diabetic mice that weren’t vibrated. For many purposes three subjects per condition is standard, but usually you do the whole experiment at least three times with independent litters. This gives you n=3 litters of mice to ensure that this wasn’t some freaky genetic issue and it helps with managing the standard deviation and measurement errors.
What Can We Learn?
This is an interesting exercise in how some science is done. They use flashy lab techniques, like next generation sequencing and flow cytometry, and show complicated statistics and graphs to make their case. The problem is that there isn’t much substance. You can discuss the levels interleukin-10 or the neutrophil encroachment of the omental mantle and throw around diversity index comparisons until the cows come home, but all of this is observational. There are no mechanistic experiments to support their conclusions.
This is an interesting story and I am genuinely curious to see whether it leads somewhere, but should we take what the authors say about whole body vibration with a pinch of salt? I’d say we’d need a desalination plant handy.
Yu, J. C., Hale, V. L., Khodadadi, H., & Baban, B. (2019). Whole Body Vibration-Induced Omental Macrophage Polarization and Fecal Microbiome Modification in a Murine Model. International Journal of Molecular Sciences, 20(13), 3125. doi: 10.3390/ijms20133125
Editor’s note: originally this article contained a short, uncritical summary of the paper and a press release put out by Augusta University. The content has been updated to more accurately represent the findings of the project and their scientific validity. Medical News Bulletin takes scientific reporting seriously. We don’t accept a claim unless there is evidence to back it up and we don’t rely on press releases to judge the quality of science.
Original story published September 20, 2019, follows below.
by Shrishti Ahuja
Whole body vibration has become a more prevalent form of therapy and exercise over time.
It has shown compelling evidence for being an effective method for reducing inflammation caused by diabetes. Inflammation is regulated by macrophages, which are cells that are part of the body’s immune system. Macrophages are able to promote and reduce inflammation.
Previous research has demonstrated that whole body vibration can assist with inflammation.
In a study, published in the International Journal of Molecular Sciences, researchers set out to investigate the mechanism by which it influences inflammation.
The study utilized two sets of male mice, where one set consisted of genetically mutated mice and the other remained a control set. The mutated mice had an altered gene that codes for the hormone leptin, thus reducing leptin production.
A lack of leptin causes these mutated mice to be susceptible to diabetes and obesity. Both sets were fed a regular diet and exposed to whole body vibration at a frequency of 30 Hertz daily for a period of four weeks.
Following the experiment, the researchers analysed abdominal adipose tissues from both sets of mice.
The study reported that whole body vibration caused significant changes in the genome of the microorganisms that were present in the body of the mice that assist with digestion. Whole body vibration improved the utilization of glucose in the body, in turn reducing the effects of inflammation, which are otherwise amplified due to an excess of glucose.
The researchers found that an increase in the bacterium Alistipes, which makes short chain fatty acids that use glucose, caused a significant reduction in inflammation. Whole body vibration was also found to increase levels of macrophages that suppressed the inflammatory pathway.
This study offers an in-depth look at the mechanisms by which inflammation occurs and is reduced through whole body vibration.
The authors were successful in identifying the bacterium Alistipes that was most significantly impacted. They were able to extend this information by directly providing a dose of the bacterium coupled with lower levels of vibration to yield similar results.
A greater understanding of these mechanisms will be beneficial to better understand and treat diabetes and related conditions.
References:
Whole body vibration shakes up microbiome, reduces inflammation in diabetes. (n.d.). Retrieved from https://www.eurekalert.org/pub_releases/2019-08/mcog-wbv080219.php