A few weeks back, I shared a post about a recent study that looked at using our old friend, Akkermansia muciniphila (a quick summary of some of the findings re: this probiotic bacteria are in a postscript below) to improve glucose tolerance and insulin levels. (I had written about this before once, back last October.) As many of you know, there’s a bi-directional association between poor glucose control and weight gain. And as I’ve been writing about extensively, obesity is one of the great health epidemics of our time – as is type 2 diabetes and its predecessor, metabolic syndrome. Akkermansia is also one of my biggest interests, as a growing body of research shows it has powerful health effects, including helping with weight loss.
A quick primer on insulin before I proceed. Firstly, remember that in order to be absorbed and utilized by your body, all carbohydrates – which are just long strings of sugar molecules – must be broken down to individual molecules in your intestines, before making it into your blood stream to feed every cell of your body. Remember too that insulin is released when those sugars hit your blood, to keep that glucose at a steady level. Blood sugar, in fact, is incredibly tightly regulated in the body as even a little too much or too little has enormously detrimental effects on us. To rapidly remove excess glucose from your blood, insulin quickly stores it away in your liver…but if your liver is “full,” it stores it as fat. If you’ve ever heard of the glycemic index, well, this is essentially the theory behind it: rapid rises in glucose cause a huge burst of insulin, which then rapidly stores the sugar as fat, so the avoidance of foods that cause this – in favor of foods that cause only slow rises in blood sugar (reducing the need for insulin release) – are thought to be helpful for weight loss. (That said though, we are learning that because of differences in the composition of gut bacteria, people have entirely different glucose responses to the same foods. I’ve written about that here. So even this gets to be an awfully complicated picture!)
Anyway, back to Akkermansia and this new research:
After I posted that story, one of my regular followers asked me what “pasteurized” A.municiphila meant, and I responded that it was heat sterilized. He wrote back saying, “But won’t that kill the bacteria?”…which yes, I assumed it would and like him, didn’t really understand why dead probiotics would have a beneficial effect. And that’s been wearing on me…but I simply haven’t had time to do more research into it. (Please, all of you understand – this blog is a labor of love. I make no money from it…and I already am a single mom caring for a profoundly autistic son…and work 2 “real” jobs as well. I’m just a little swamped for time! So Stephen, I’m sorry it’s taken me a couple of weeks to get back to you on that!)
Therefore, though, I was very excited when an article appeared yesterday on Gut Microbiota for Health explaining this phenomenon.[i]
The article was actually written by one of the researchers involved in these studies. He starts by stating that in 2017, his team found that “…a pasteurized form of A. muciniphila led to a stronger reduction in fat mass development, insulin resistance and dyslipidemia in mice when compared with the live bacterium.” Since they didn’t know if it would have the same effect in humans, he just led a 3 month long randomized, double-blind, placebo-controlled study (so the gold standard) looking at this in 32 overweight or obese people and found, again, that this heat-inactivated (you read that right: INACTIVATED) form of A.muciniphila, “…helps to limit the increase of different cardiovascular risk factors in subjects who are overweight and obese.” How crazy is that?![ii]
The people in the study did not change anything else during the trial, so no diets and no increase in physical activity. They were then, in randomized fashion, given 100 billion of either live A.muciniphila or this inactivated, pasteurized form. Only those treated with the latter – the inactive form – had “…lower circulating insulin levels, reduced insulin resistance indices, lower total blood cholesterol and lower circulating dipeptidyl peptidase IV (DPP-IV) when compared with the placebo group. The enzyme DPP-IV has been involved in modulating glucose homeostasis, satiety and emotional-affective behavior.” So it not only improved glucose control – it also improved feelings of being full?! This inactive form also reduced white blood cell counts (which are apparently elevated in obesity and “associated with glucose intolerance”); AND reduced the amount of proinflammatory byproducts from gut bacteria (lipopolysaccharides, or LPS); AND it reduced liver inflammatory markers.
Wait…what?! How is this possible?!
Well, they don’t know for sure but…here’s the theory. They know from previous studies that the outer membrane of A. muciniphila contains a protein called Amuc_1100 which seems to induce many of the benefits associated with giving mice and humans pasteurized A. muciniphila. The researchers therefore believe that this mild heat inactivation, or pasteurization, allows the components of the bacteria’s cell wall greater freedom to exert these benefits.
Both forms of the A. muciniphila were well tolerated, by the way, and as you’ve read on this blog before (see below), the live form also exerts huge benefits. So…you’ll be happy to read the last sentence of this article: “Our next steps include planning larger-scale tests and commercializing the bacteria in the form of food supplements.”
p.s. As promised, here are just 3, of several, other posts on The Biome Buzz related to Akkermansia muciniphila:
[ii] Depommier C, Everard A, Druart C, et al. Supplementation with Akkermansia muciniphila in overweight and obese human volunteers: a proof-of-concept exploratory study. Nat Med. 2019. doi: 10.1038/s41591-019-0495-2.