Towards Personalized Nutraceuticals Based on Microbiota and Metabolic Profile
Prediabetes is an increasingly common condition and represents an important risk factor for the progression to type 2 diabetes. In addition to lifestyle interventions, there is growing interest in nutraceutical strategies aimed at improving glycemic control.
A recent study published in Nature Microbiology analyzed the effectiveness of a broccoli sprout extract (BSE), a natural source of sulforaphane, in adults with prediabetes. This was a randomized, double-blind, placebo-controlled clinical trial lasting 12 weeks.
Men and women between 35 and 75 years of age were included, with a BMI between 27 and 45 kg/m² and fasting blood glucose values between 6.1 and 6.9 mmol/L. Of the 450 subjects screened, 89 were randomized: 35 received the broccoli extract, 39 the placebo.
Main results
The primary endpoint was a reduction in fasting blood glucose of at least 0.3 mmol/L compared with placebo. This goal was not achieved in the overall population.
However, the analysis showed an average decrease of 0.2 mmol/L in subjects treated with BSE compared with the placebo group, a statistically significant result even if of limited magnitude. Other metabolic parameters (lipids, HbA1c, insulin resistance index) did not show relevant differences.
The immediate conclusion is that the overall effect of broccoli sprout extract on glycemic control is modest, but not negligible.
Responder subgroups
Looking more closely, the researchers identified subgroups with a more marked response. In particular, individuals with:
- mild obesity,
- lower insulin resistance,
- lower insulin secretion,
- absent or minimal hepatic steatosis,
showed an average reduction in fasting blood glucose of 0.4 mmol/L, a value close to the clinically relevant threshold.
These data suggest that the effectiveness of sulforaphane is not uniform but depends on the baseline metabolic profile.
The role of the gut microbiota
Another decisive element emerged from the analysis of the gut microbiota. Subjects who responded better to treatment already had a higher baseline abundance of Bacteroides carrying a transcriptional regulator (BT2160).
This gene is part of a bacterial operon involved in the conversion of inactive glucosinolates into active sulforaphane. In other words, without the right intestinal flora, the broccoli extract is not “activated” with the same effectiveness.
The presence of BT2160 was found to be correlated both with higher serum sulforaphane levels and with a more consistent improvement in blood glucose.
Safety and tolerability
Treatment with BSE was well tolerated. The adverse events reported were mainly gastrointestinal disturbances (loose stools, diarrhea, nausea, reflux), more frequent in the treated group compared to placebo, but always of mild or moderate severity.
No serious adverse events occurred, and the majority of participants completed the trial. For a condition such as prediabetes, where the willingness to accept side effects is limited, this safety profile is a positive factor.
Towards personalized nutraceuticals
The central message of the study is that the benefit of sulforaphane is not the same for everyone. Its effectiveness depends on the combination of:
- metabolic physiology (degree of insulin resistance, insulin secretion, obesity, fatty liver),
- ability of the gut microbiota to convert the precursor into active sulforaphane.
This perspective paves the way for a precision nutritional medicine approach, in which clinical and microbiological biomarkers can help identify who will truly benefit from an intervention with BSE or, more generally, from a crucifer-rich diet.
Practical implications
For people with prediabetes, BSE is not a miracle cure but could represent a complementary support. In the right individuals, with a favorable metabolic and microbial profile, it can make a tangible contribution to reducing blood glucose.
From a dietary point of view, the study reinforces the importance of including cruciferous vegetables such as broccoli, cauliflower, and Brussels sprouts in the daily diet. These foods provide not only sulforaphane precursors but also fibers and micronutrients that support metabolic health and microbial diversity.
Limitations and future prospects
The study nevertheless has limitations to consider. The 12-week duration does not allow assessment of whether the observed benefits actually reduce the risk of progression to diabetes. In addition, the sample size remains modest for drawing definitive conclusions.
Therefore, larger and longer trials will be needed to confirm the results, better identify responder subgroups, and understand whether modulation of the microbiota can be exploited as a therapeutic lever.
The clinical trial shows that a broccoli sprout extract rich in sulforaphane can reduce fasting blood glucose in people with prediabetes, even if the average effect is limited. The effectiveness becomes more evident in subgroups with a favorable metabolic profile and with a microbiota capable of activating the compound.
These data open concrete prospects for personalized nutraceuticals, where it is not only “what” is taken that matters, but also “who” takes it and with what microbial heritage.
If your company is interested in creating or manufacturing a product for Prediabetes:
Source: February 10, 2025, Effect of broccoli sprout extract and baseline gut microbiota on fasting blood glucose in prediabetes: a randomized, placebo-controlled trial, Nature Microbiology.
