Could Gut Flora Be Linked to Diabetes?
by Frank Ervolino, N.D., L.Ac.
There have been a large number of research papers of late dealing with the relationship between disease and the flora of the gut. There was a recent study from the University of Copenhagen’s Department of Biology and Novo Nordisk Foundation Center for Basic Metabolic Research, which found that people who have type 2 diabetes also have a unique gut bacteria profile.
Not only does this offer a therapeutic approach to treatment, it may also be a causal factor in the disease. Let’s dig in!
Understanding Your Gut Flora
In utero, an infant’s gut is sterile, but bacterial seeding starts immediately after birth. Vaginally born infants will establish both maternal vaginal and environmental bacteria. Those born via a caesarean procedure will have predominantly more environmental bacteria.
A healthy vagina contains mostly Lactobacillus bacteria. Bifidobacteria and other components of the normal human gut flora are obtained through environmental contact with soil and other terrain such as Aunt Kathy’s neck or fingers.
In fact, this is the evolutionary basis for an infant’s tendency to put everything in their mouth. It has evolved as a trait necessary for survival, especially when the infant didn’t receive the maternal gut flora foundation of Lactobacillus from vaginal delivery.
Your Internal Critters
It is estimated that there are up to 1.5 kg of bacteria in the developed human gut, which maintain a very delicate equilibrium. The divisions found in the intestines were:
Approximately 90 percent of your gut flora is comprised of the first two divisions—Bacteroidetes and Firmicutes. The remaining divisions account for the remaining 10 percent.
The different strains of bacteria then fall into one of these six divisions. For example, Lactobacillus acidophilus is in the Firmicutes division and Bifidobacteria is in the Actinobacteria division.
The Bacteria-Diabetes Connection
So what does this all have to do with diabetes? According to a study published in the October 2012 issue of Nature, quite a bit.
The study showed that test subjects with type 2 diabetes suffered from bacterial imbalances in their gut.1 Specifically, they had a decrease in their butyrate-producing bacteria. This is significant because butyrate is the preferred source of energy, repair and maintaining health of cells in the human digestive system. In the colon, the predominant butyrate-producing bacteria are the Clostridium coccoides and the Eubacterium rectale groups.
The study also found a rise in the number of opportunistic gut pathogens. Researchers also found an enrichment of sulphate reduction, which is important because sulphate selectively inhibits butyrate oxidation, a hallmark of digestive conditions such as ulcerative colitis. Increased oxidative stress resistance was also noted, implying that there is increased damage occurring to epithelial (skin tissue) cells.2
This is an engaging study that is part of a wider body of research being done on the gut flora and how it relates to the overall health of humans. Of course, many news editors will read the research and quickly make the leap that we can cure type 2 diabetes by treating the gut flora, but that remains to be seen.
What we do know is that people who have type 2 diabetes are under a tremendous amount of metabolic stress due to their body’s inability to properly place the glucose from their bloodstream into the cells of the body.
Type 2 diabetes is characterized by damage systems that help you transport glucose throughout your body. In areas of the body that do not have these glucose transport systems—i.e., the nerves, eyes and brain—you can see other forms of metabolic stress such as fructose-induced pressure in the eyes or AGEs (advanced glycation end products), which can result in conditions such as peripheral neuropathy, cataracts and damage to blood vessels and brain function.3
One thing the study pointed out was that there is damage to the intestinal wall. This means that certain proteins can cross the intestinal wall and trigger white blood cells to release an inflammatory cascade, resulting in systemic inflammation.4 This is no surprise, given that insulin resistance is associated with low-grade chronic systemic inflammation.5
If you combine this with bacterial endotoxins released as a result of intestinal dysbiosis (imbalance in bacteria), plus increased blood glucose levels, you can see how gut flora plays a role in either increasing or decreasing the damage that can result from type 2 diabetes.
Protect Your Gut, Protect Your Health
To help you protect your gut health, preserve and balance your gut flora and decrease your risk of type 2 diabetes at the same time, here are dietary and supplement therapies.
Prebiotics are non-digestible sugars that work to fertilize healthy gut flora such as the highly beneficial Bifidobacteria and Lactobacillus.6 Bifidobacteria in particular have been shown to decrease colonic inflammation by a factor as high as 10 times more than other microbiota in the intestine.7
Prebiotics such as fructooligosaccharides (FOS), oligofructose and inulin have been found to be bifidogenic in nature.8 FOS is commercially available and can be used to modulate the growth of beneficial bacteria.
Inulin has also been used in commercial foods. One example is Dreamfields®, a semolina pasta with added inulin. Pasta with inulin has been shown in studies to improve cholesterol ratios, triglycerides and fasting glucose levels.9 The use of prebiotics produces fast results, but it should be noted that these positive benefits can disappear in as little as one week when you stop taking the prebiotic.10
Prebiotics have also been shown to be effective in protecting against weight gain and even increasing levels of Bifidobacteria in the gut.11-12
There are so many species of probiotic bacteria out there that I could write a book on this topic alone, but for this article, I will concentrate on the two major commercially available forms and point out their function and differences—Lactobacillus and Bifidobacteria.
The Lactobacillus rhamnosus species has been commercially available for many years and is the most commonly known and used probiotic. The major effect it seems to exert in the gut is lowering blood glucose levels post-meal.13
Lactobacillus delbrueckii supplementation also had a positive effect on fasting blood glucose levels.13 Studies show that heat-treated Lactobacillus did not have the effects that viable live bacteria did, which negates the value of food products that have their cultures added before they have been pasteurized, such as yogurt.
And speaking of food sources of probiotics, another problem lies in the fact that the number of colony forming units (CFUs) of bacteria drops over time. This means that what may be in a yogurt when it leaves the factory may not be in it when you eat it.
Bifidobacteria has become popular over the past five years—and with good reason. Bifidobacteria have been shown to reduce inflammation at the gut wall better than many other species of bacteria.3-4 Specifically, different strains of Bifidobacteria seem to inhibit NF-KappaB, a metabolic factor involved in chronic intestinal inflammation.
When it comes to butyrate-producing bacteria, Eubacterium rectale can be influenced by diet and lifestyle choices. For example, a study found that eating almonds increased colonic populations of Eubacterium.14
Another study showed that NSAID usage in the elderly resulted in a decrease of this butyrate-forming bacteria.15 Fortunately, Bifidobacteria supplementation can increase Eubacterium rectale populations.16
The Bottom Line
Given all this, paired with that 2012 study from Nature, it’s natural to ask the question: Can bacteria directly cause diabetes? The answer is most likely no. However, your gut flora can play a role in the development of type 2 diabetes.
And that development follows, in large part, the lifestyle choices you make. If your lifestyle choices—soft drinks, high-carbohydrate/low fiber diet and excessive use of pharmacological drugs—lead to dysbiosis, then there is a risk of increased inflammation. This, combined with dietary high blood glucose levels, can accelerate damage to both glucose regulated and non-regulated tissue, and this in turn can lead to type 2 diabetes and various other medical problems.
In Chinese medicine, the solution to dysbiosis is to eat cooked and not raw food and to increase consumption of aromatic herbs such as ginger, fennel and cinnamon. You can also replenish flora with pre- and probiotics, and use herbs that harmonize the digestion, such as bladderwrack, Fucus vesiculosus, barberry root (Berberis vulgaris) and dandelion (Taraxacum officinale).
By using this combination of dietary changes, supplementation and herbs, you not only improve your gut health, but protect against type 2 diabetes as well. Talk about your smart medicine!
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