Diabetes: a diet rich in fiber lowers blood sugar

A recent study published in the prestigious scientific journal Science shows that a diet very rich in fiber promotes the establishment of beneficial intestinal bacteria, which leads to a reduction in chronic hyperglycemia responsible for the complications of type 2 diabetes.

Type 2 diabetes, alone responsible for more than 80% of diabetes cases, has become in recent years one of the main chronic diseases affecting the entire world population. This disease mainly affects people who are overweight, in particular those whose excess fat is localized in the abdominal area: in these people, the organs no longer manage to capture and store sugar as effectively in response to insulin. (they are said to be insulin resistant), which leads to a state of chronic hyperglycemia.

Clinically, measurement of glycated hemoglobin is a commonly used method to determine the presence of chronic hyperglycemic conditions. This measurement is based on the property of sugar to chemically bind to proteins, in this case the hemoglobin contained in red blood cells. Since the lifespan of red blood cells is approximately 120 days, the level of sugar-bound (glycated) hemoglobin represents a marker of average blood sugar levels over a two-month period. When the level of one of the hemoglobin subgroups (HbA1c) exceeds about 7%, then it is called chronic hyperglycemia.

This measure is very important, because hyperglycemia is a condition that damages blood vessels and considerably increases the risk of cardiovascular diseases such as heart attack and stroke, as well as various pathologies such as renal failure (progressive loss of functions of the kidney), retinopathies (important eye diseases causing blindness) or circulation problems in the lower limbs (arteritis).

A diet high in fiber stabilizes blood sugar

The mechanisms responsible for the development of insulin resistance and type 2 diabetes are very complex, but several studies suggest that the intestinal microbiome, that is to say the hundreds of billions of bacteria which naturally reside in the system. digestive, could play a very important role. These bacteria feed by fermentation of the complex starches and dietary fibers present in the food, which generates (among other things) short-chain fatty acids with anti-inflammatory activities. Low production of these fatty acids has been reported to be associated with an increased risk of type 2 diabetes, suggesting that increased fiber (and therefore short-chain fatty acid) intake may exert an influence. positive about this disease.

90% of participants regain normal blood sugar levels

The results of a randomized clinical study recently published in the journal Science support this. In this study, participants diagnosed with type 2 diabetes were randomly assigned to two groups, one where patients were advised to adopt a standard approach (exercise, low-calorie diet, avoid sweets) and another where the patients had to consume every day a mixture very rich in fibers coming from various sources (oats, legumes, vegetables, seeds, nuts) as well as a preparation of pre-biotics (to promote the growth of intestinal bacteria). Throughout the duration of the study (3 months), blood samples were taken to determine blood glucose (measurement of HbA1c levels) and stool samples were collected to determine the strains present in the intestinal microbiota .

Psssssst :  What are the healing properties of hemp milk?

This approach has made it possible to show that a diet rich in fiber considerably improves glycemic control: while approximately 50% of patients treated in the standard way had adequate glycaemia (HbA1c < 7%) after 12 weeks, it is 90% of participants in the “high fiber” group who achieved this goal.

Fiber feeds good gut bacteria

This remarkable improvement is a consequence of the drastic changes in the composition of the intestinal microbiota of people with a high fiber intake: the scientists observed that these people presented a greater microbial diversity and higher quantities of about fifteen producing bacterial strains short chain fatty acids, especially acetate and butyrate. The increased presence of these fatty acids stimulates the production of glucagon-lice peptide-1 and peptide YY, both known to stimulate insulin secretion, confirming that the improvement in blood sugar seen in people fed high fiber is a direct consequence of changes in the gut microbiota.

The Western diet is very low in fiber (15 g per day instead of the recommended 30-40 g) and the best way to remedy this situation is to increase the total consumption of vegetables, for example legumes, cereals ( especially whole grains), nuts, fruits and vegetables. This is not only positive for people with diabetes, but also for the prevention of cardiovascular disease and certain types of cancer (colon, in particular).


Zhao L et al. Gut bacteria selectively promoted by dietary fibers alleviate type 2 diabetes. Science 2018; 359: 1151-1156.

* Presse Santé strives to transmit medical knowledge in a language accessible to all. In NO CASE can the information given replace medical advice. []

Back to top button

Adblock Detected

Please disable your ad blocker to be able to view the page content. For an independent site with free content, it's literally a matter of life and death to have ads. Thank you for your understanding! Thanks