Data published in International Journal of Endocrinology indicated that six months of supplementation with 15 grams per day of inulin led to significant improvements in fasting insulin and HOMA-IR, compared to baseline levels.
“These findings suggest that inulin may be a potentially novel and inexpensive intervention for prediabetes,” wrote the researchers from the Chinese Academy of Medical Sciences, Peking Union Medical College, and Tsinghua University.
Consistent with the literature
The study adds to an ever-growing body of science supporting the potential blood sugar management and anti-diabetes benefits of inulin-type fructans.
Indeed, a systematic review and dose–response meta-analysis of 33 clinical trials, published in the Journal of Translational Medicine in 2019 (17, 410, doi: 10.1186/s12967-019-02159-0) concluded that inulin-type fructan supplementation was associated with significant improvements in a range of measures, including fasting blood glucose, HbA1c, fasting insulin, and HOMA-IR. The 33 trials included a range of participants, from healthy subjects to overweight and obesity populations and people with pre-diabetes and type 2 diabetes. The effects were better in the prediabetics and diabetic populations, wrote the reviewers.
The researchers behind the new study note that, while inulin has already been studied in prediabetics, the “effect of inulin on the intestinal microbiota ecosystem in prediabetic individuals remains unclear.”
Forty-nine pre-diabetic subjects with an average age of 57 and an average BMI of 25.1 kg/m2 were recruited to participate in the study. All of the subjects received a daily supplement with 15 g of inulin for six months.
The data indicated that the inulin supplement was associated with increases in the relative abundance of Actinobacteria, Bifidobacteriales, Bifidobacteriaceae, Lactobacillaceae, Bifidobacterium, Lactobacillus, and Anaerostipes after three and six months. On the other hand, decreases in the relative abundance of potential pathogen-like bacteria, such as Alistipes and Desulfovibrionaceae (key producers of endotoxins), were also observed.
“Alistipes have been shown to be highly abundant in T2DM patients and positively correlate with the inflammatory state, driving insulin resistance,” wrote the researchers. “… our findings showed that the family Desulfovibrionaceae dominated in prediabetes before inulin intervention, but not found at 3 and 6 months after inulin supplement.
“Taken together, the inhibition of potential pathogen-like bacteria and increase in SCFAs [short-chain fatty acid] producing beneficial bacterium might be responsible alleviating insulin resistance.”
The researchers concluded: “… owing to the small sample size and absence of an independent control group of this study, larger scale and randomized controlled trials are therefore warranted to further confirm our findings.”
Source: International Journal of Endocrinology
Volume 2021, Article ID 5579369, doi: 10.1155/2021/5579369
“Dietary Supplementation with Inulin Modulates the Gut Microbiota and Improves Insulin Sensitivity in Prediabetes”
Authors: X. Wang et al.