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Intestinal Microbiota: A Surprising Clue In Diabetes

« WeCare Blog | October 19, 2022 |
Food and drink
Intestinal Microbiota: A Surprising Clue In Diabetes

Is it possible that eating a plate of spaghetti can be processed differently in each body? The answer is yes, because each organism metabolises and absorbs carbohydrates in a certain way, and that is due to a variable that was not considered until very recently: the intestinal microbiota, something we’re just beginning to discover.

Can We Personalise Diabetes Treatment Through Intestinal Microbiota?

Intestinal microbiota, commonly known as intestinal flora, is the set of microorganisms that exist inside our bodies. These tiny microorganisms are with us since birth and “are considered to be another organ of our human physiology,” according to José Manuel Fernández-Real, M.D., Ph.D. Professor of Medicine at the University of Girona, and Head of the Endocrinology Section of Hospital Dr. Josep Trueta in Girona, Spain. In fact, within our gastrointestinal tract we have over a hundred trillion microorganisms.1

Up until a few years ago, endocrinology and nutrition professionals have held similar views as to how to manage the diet of a person with diabetes. A pasta dish of about 100 grams has approximately 25 grams of carbohydrates, and it was believed that those 25 grams of carbs behaved the same way in all patients, assuming that the glycaemic absorption of food was the same for everybody.

Today, we are beginning to understand, according to Dr. Fernández-Real, that "the intestinal microbiota of each person is different, and the microbiota of a person living with diabetes is clearly different from that of a person not living with diabetes." Although further research is still needed around this issue, what’s certain is that the absorption of carbohydrates varies according to each person, and the intestinal microbiota clearly do play a role.

The Complexities of Customisation

We are, without a doubt, facing “a complicated variable that’s difficult to measure, but that can get us closer to the reality of each person's metabolism.” Thanks to studies on the intestinal microbiota, "the glycaemic index of food, a value that’s highly variable and that’s been questioned for many years, can be better predicted if the composition of the intestinal microbiota is known." And it is precisely the knowledge of this microbiota that can help optimise the dietary management of people with living diabetes, making it more personalised and effective.

A few years ago, Dr. José Manuel Fernández-Real published an article in the journal Nature Medicine2 in which he demonstrated that certain drugs could alter the intestinal microbiota of a person. The study focuses on type 2 diabetes and the impact that metformin has had on the intestinal microbiota of patients.

The intestinal microbiota fluctuates; in part, it depends on diet, and the composition of microorganisms that it contains can have an impact on the glycaemia of a person. To date, most of the intestinal microbiota measurements have been made through stool cultures. However, the doctor adds, “With these techniques, up to 80% of the information is lost. The most precise techniques are those that analyse the DNA sequences of our intestinal microbiota, where we can find bacteria, fungi, viruses and even microparasites.” There’s a whole set of elements that undoubtedly affect the digestion of a person living with diabetes and their subsequent glycaemic management.

Final Thoughts

While most of us would probably prefer not to think about the tiny microorganisms in our guts while eating a plate of spaghetti, Dr. Fernandez-Real’s research gives us a key clue in the development of personalised diabetes management. In his own words, "Putting microbiota in the equation is discovering an answer that’s closer to reality, but in turn, enormously more complex." So, as research continues to sleuth out all the clues, stay tuned and enjoy that spaghetti!


  1. Thursby E, Juge N. Introduction to the human gut microbiota. Biochem J. 2017;474(11):1823-1836.
  2. Wu H, Esteve E, Tremaroli V. et al. Metformin alters the gut microbiome of individuals with treatment-naive type 2 diabetes, contributing to the therapeutic effects of the drug. Nat Med. 2017;23:850–858.

The content of this article is for informational use and is not in any case should it replaces the consultation of the instructions for use of the device, or the opinion, diagnosis or treatment prescribed by your diabetes healthcare team. Always speak with your diabetes healthcare team for diagnostic and treatment information and strictly follow your diabetes healthcare team’s instructions. Medtronic cannot be held responsible in any way for any damage caused, or presumably caused, directly or indirectly, by the information contained in this article.

*Editor’s note: This article has been adapted and reproduced from a post published on Medtronic Diabetes Australia.