With recent advances in technology allowing scientists to examine the make up of microorganisms (known as microbiota) in our guts, it seems each month there is a new disorder or disease found to be linked someway to the trillions of members of the VIP gut club.
Researchers from the University of British Columbia, Vancouver sum it up well in an article appearing in the July issue of this year’s Physiological Reviews when they write:
“The microbiota is intimately involved in numerous aspects of normal host physiology, from nutritional status to behavior and stress response. Additionally, they can be a central or a contributing cause of many diseases, affecting both near and far organ systems.” 
One of the latest chronic diseases to be linked with altered gut microbiota is Type 2 Diabetes. The clues were there some 4 years ago when researchers from Washington published a groundbreaking article showing that the relative proportions of the two dominant groups of beneficial bacteria in the human gut, (i.e. Bacteroidetes & Firmicutes) were different in obese versus lean people and that they also could be changed through diet.
As it turns out, more recent studies have shown that type 2 diabetics may differ from healthy people in the number and type of species within key bacterial groups such as Bifidobacterium and Bacteroides. Type 2 diabetes is a chronic disease, with an increasing prevalence over the past few decades. Scientists have been at a bit of a loss to explain this increasing prevalence solely due to changes in the human genome, nutritional habits, or the reduction of physical activity in the average person. So it would make sense that another factor, such as subtle variations in gut bacteria, may explain the increasing prevalence of type 2 diabetes.
One of the key mechanisms thought to mediate the typical effects of type 2 diabetes is low-grade inflammation. Not surprisingly, this too has been traced back to the composition of the gut microbiota in response to a high-fat diet. Lipopolysaccharide (LPS) is the name given to a broad class of toxins generated by bacteria and thought to induce inflammation. High-fat diets have been shown to increase the proportion of LPS-containing microbiota in the gut.
But back to our good friends Bifidobacterium and their link with type 2 diabetes. Prebiotic dietary fibers have been used to increase the levels of these friendly guys leading to improved glucose and insulin control and normalized low-grade inflammation.
Bifidobacterium are one group of bacteria that can be increased through both diet and supplementation. It stands to reason that these good bacteria should be assessed in patients with type 2 diabetes and to assist their clinician's decisions about treatment strategies. ~Wesley Hurrell
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- Cani PD, et al. Selective increases of bifidobacteria in gut microflora improve high-fat-diet-induced diabetes in mice through a mechanism associated with endotoxaemia. Diabetologia. 2007;50(11):2374-2383.