A natural compound found in broccoli sprouts, called sulforaphane, may help lower blood sugar levels in people with prediabetes. This was discovered in a study conducted by researchers at the University of Gothenburg in Sweden. The study suggests that some people may benefit more than others from this compound, depending on their health conditions.
Prediabetes is a stage before type 2 diabetes where blood sugar levels are higher than normal but not high enough to be classified as diabetes. If left untreated, prediabetes can develop into type 2 diabetes, which increases the risk of heart disease, kidney problems, and other serious health issues.
Past research by the same university showed that sulforaphane helped lower blood sugar in people with type 2 diabetes. In 2017, a study found that patients who took high doses of sulforaphane extracted from broccoli sprouts had significantly lower blood sugar levels.
Based on these earlier findings, researchers wanted to see if sulforaphane could also help people with prediabetes.
In the new study, published in Nature Microbiology, the team, led by Professor Anders Rosengren, tested the effects of sulforaphane on 89 people with prediabetes. These participants were overweight or obese and between 35 and 75 years old.
They were randomly divided into two groups: one group took sulforaphane supplements, while the other took a placebo (a pill with no active ingredient). Neither the participants nor the researchers knew who received the actual sulforaphane.
After 12 weeks, researchers measured fasting blood sugar levels (the level of sugar in the blood after an overnight fast). The results showed that people who took sulforaphane had a greater reduction in fasting blood sugar compared to those who took the placebo. The difference was even larger in certain participants who shared specific health characteristics.
These participants had mild early-stage diabetes, a lower body mass index (BMI) within the study range, less insulin resistance, lower rates of fatty liver disease, and lower insulin secretion. This suggests that sulforaphane may work better in people with these characteristics.
The study also explored the role of gut bacteria. In collaboration with Professor Fredrik Bäckhed, the researchers found that a specific type of gut bacteria could interact with sulforaphane and boost its effect. Among people who had this particular gut bacterium, the reduction in fasting blood sugar was even more significant.
The numerical findings showed that, on average, people taking sulforaphane had a 0.2 millimole per liter drop in fasting blood sugar compared to the placebo group. In the subgroup of people with the right health characteristics, the reduction was 0.4 millimoles per liter. In those who had both the health characteristics and the gut bacterium, the decrease was 0.7 millimoles per liter.
Prediabetes affects about 10% of people in Sweden, and there is no standard medical treatment for it. Many people do not know they have prediabetes because it does not always cause symptoms. However, early detection and lifestyle changes, such as eating a healthy diet, exercising, and maintaining a healthy weight, can prevent it from turning into type 2 diabetes.
Professor Rosengren believes that these findings could lead to a more personalized way of treating prediabetes. He suggests that sulforaphane could be used as part of a “precision treatment”—a targeted approach that takes individual differences into account.
However, he also emphasizes that healthy lifestyle choices remain the most important way to manage blood sugar and prevent diabetes.
This study highlights how food compounds, like sulforaphane, can work together with the body’s systems, including gut bacteria, to influence health. These findings may open the door for further research into how diet and gut health affect the effectiveness of different treatments.
While more studies are needed, sulforaphane from broccoli sprouts could be a promising option for people at risk of developing diabetes.
If you care about diabetes, please read studies about high vitamin D level linked to lower dementia risk in diabetes, and green tea could help reduce death risk in diabetes.
For more information about nutrition, please see recent studies that blueberries strongly benefit people with metabolic syndrome, and results showing vitamin D could improve blood pressure in people with diabetes.
The research findings can be found in Nature Microbiology.
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