Our gut microfloras are important cogs in the wheels of our biological machinery. From assisting in digestion and absorption to orchestrating metabolic and immune responses, gut microbes play a huge role. But when these gut microbes are bombarded by the highly processed foods of the Western diet (sugar, carbohydrates, and processed fats), the composition of these microbes is altered. This is a phenomenon known as dysbiosis.
Dysbiosis is linked with intestinal permeability (leaky gut). When bacterial fragments and/or bacterial DNA enter the sterile environment of the body, havoc, in the form of inflammation, ensues. This is why both leaky gut and dysbiosis are linked to obesity and diabetes.
Further Reading: Dysbiosis of the blood linked with atherosclerosis development, heart disease and inflammation
JAPANESE SCIENTISTS FIND BACTERIAL IMBALANCES IN THE BLOOD AND INTESTINES OF DIABETIC PATIENTS
Much of the research linking gut microbe imbalances has been conducted on Western and European Caucasians. Researchers from Japan sought to see if changes in the guts of Japanese diabetics were linked to diabetes, and they were.
The scientists studied the blood and feces of 50 diabetic patients and 50 controls. The study revealed common metabolic and inflammatory findings between diabetics and non-diabetics, namely increased body mass index (BMI), fasting glucose, HbA1c, triglyceride levels, high-sensitivity C-reactive protein (hs-CRP), and interleukin-6 (IL-6), a common by-product of inflammation.
The scientists also found significant differences in the gut microflora of the diabetics vs non-diabetics, namely lower counts of obligate anaerobic bacteria groups, that of the Clostridium coccoides, Atopobium cluster, and Prevotella. C coccoides and Atopobium cluster levels are inversely linked with inflammation: higher levels are tied to lower hs-CRP. However, diabetics tended to have higher levels of the facultative anaerobes Lactobacillus genera compared to the healthy, non-diabetic controls. More specifically, diabetic patients had significant increased counts of Lactobacillus reuteri and Lactobacillus plantarum.
Does this mean that L reuteri and L plantarum are bad? I don’t think so. But this study and several others have linked increased levels of the Lactobacillus genus with obesity and metabolic challenges. It could be that diets rich in processed carbohydrates increase the quantities of these facultative anaerobic bacteria.
LEVELS OF ENDOTOXIN-HARBORING BACTERIA AND ENDOTOXIN-BINDING PROTEINS ARE HIGHER IN DIABETICS
The gram-negative bacteria cluster Enterobacteriaceae was higher in the diabetic group. Recall that gram-negative bacteria harbor lipopolysaccharides or endotoxins, which drive inflammation and insulin resistance. This may be one reason why diets rich in processed foods are also linked with diabetes and obesity.
Blood levels of lipopolysaccharide binding protein (LBP) increased in the diabetic group compared to the control group. LBP correlates strongly with body fat in the diabetic group, as well as inflammation and insulin resistance.
GUT BACTERIA COMPOSITION IS IMPROVED WITH METFORMIN AND INCRETIN THERAPY
Metformin is a common medication used to treat insulin resistance and diabetes. Although it has long been known to improve insulin and metabolic signaling, recent science suggests that metformin may beneficially alter the gut microflora. This new study showed just that. Diabetic subjects taking metformin had increased levels of Enterobacteriaceae and Staphylococcus.
Similarly, diabetic subjects taking a different class of medication (the incretin drug acarbose) were found to have increased levels of Bifidobacterium, Lactobacillus counts, Lactobacillus gasseri, and Enterococcus.
ORGANIC ACIDS AND SHORT-CHAIN FATTY ACIDS
We recently discussed short-chain fatty acids HERE. As mentioned earlier, diets rich in fiber are linked to increased concentrations of short-chain fatty acids (SCFAs), while diets rich in fats are linked to lower levels of SCFAs in the stool. This study showed that levels of SCFAs were lower in subjects who had diabetes for a longer duration and who ate diets rich in saturated fat. However, in diabetic subjects, levels of SCFAs correlated with dietary intake of carbohydrates.
HIGHER LEVELS OF BACTERIA IN THE BLOODSTREAMS OF DIABETICS
Remember that our immune system has finely tuned receptors that sense and detect bacterial antigens (particles, DNA, etc.). Once these compounds are detected, inflammation ensues. Inflammation is linked with insulin resistance, the precursor to diabetes.
Well…gut bacteria were detected in the bloodstreams of 28 percent of diabetic patients but only in 4 percent of non-diabetic controls.
Diabetes is linked to shifts in Japanese subjects. It is quite possible that diets rich in processed meats, carbohydrates, and lipids skew the gut microbiome and cause leakage of bacterial particles into the bloodstream. This initiates inflammation, which in turn perturbs insulin signaling.
One way to mitigate this is to eat more “real” food, with a special emphasis on fermented foods, color-rich herbs, spices, fruits, vegetables, and polyphenol-rich teas. Studies show these foods facilitate the growth of healthy gut bacteria and increase levels of Bifidobacterium, which prevents leaky gut and reduces endotoxin absorption.
1) Belly Fat Effect unveils the whole story about diet-gut bacteria interactions, the circadian clock system and metabolism, fat burning, appetite, and much more.
2) Diabetes Care 2014