Prebiotics and Their Impact on Type 1 Diabetes

The different types of bacteria in our digestive system (also called “intestinal microbiota” or “intestinal flora”) have been widely studied in the last few years for their potential positive or negative impacts on our health. The human intestine hosts more than 400 different species of bacteria that amount to approximately 100,000 billion bacteria. They help us keep a healthy digestive system and strong immune system (natural defences, white blood cells, antibodies, etc.).

An imbalanced intestinal microbiota could contribute to several illnesses, including diabetes and obesity. In fact, this imbalance is observed in people living with type 1 diabetes (T1D) even before their diagnosis. 

Studies have shown that addressing this imbalance could delay the onset of T1D in mice, and increase the secretion of intestinal hormones that promote insulin secretion when blood sugar is high, slow down digestion and decrease the secretion of glucagon (a hormone that raises blood sugar). 

In order to establish a cause-and-effect relationship, it’s important to find out whether altering the intestinal flora has any impact on functions such as the ability to secrete insulin or to control blood sugar.

The intestinal flora can be altered in two ways: 

  • By taking prebiotics, which boost “good” intestinal bacteria. They’re found, for instance, in dietary fiber.
  • By taking probiotics, which are live bacteria or active yeast that could be beneficial to our health. For instance, lactobacilli and bifidobacteria are probiotics that are often found in yogurt.

Researchers from the University of Calgary, in Canada, have studied the effect of prebiotics on 43 children living with T1D. 

They found that they had no impact on glycemic control, but that they improved C-peptide levels in the short term.

The study also found no positive impact on hemoglobin A1c (A1c) after three months of taking prebiotics. 

But participants who took prebiotics had their C-peptide levels increase, while those who took placebos had theirs decrease. The C-peptide level measured through a blood test is used to assess the amount of insulin your pancreas is able to produce.

What about the long term?

It’s still unclear whether the presence of T1D alters the intestinal flora or whether flora abnormalities increase the risk of developing T1D. However, the findings suggest that taking prebiotics in the longer term could help improve the functioning of the pancreas.

New studies will be needed to look further into this issue and determine whether, in the longer term, prebiotics could lead to a simpler and likely less expensive treatment for people with type 1 diabetes.

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  • Ho, J. et al. (2019). Effect of Prebiotic on Microbiota, Intestinal Permeability, and Glycemic Control in Children With Type 1 Diabetes. The Journal of Clinical Endocrinology and Metabolism; 104(10); p. 4427–4440.

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