- The active ingredient in broccoli sprouts is sulforaphane.
- Sulforaphane was shown to tamp down glucose production in liver cells growing in culture and altered liver genes in mice away from the diseased state.
When the researchers gave concentrated broccoli sprout extracts to 97 human type 2 diabetes patients in a 12-week randomized placebo-controlled trial, obese participants who entered the study with dysregulated disease demonstrated significantly decreased fasting blood glucose levels compared to controls.
As we can see, in a randomized placebo-controlled trial (gold standard), we have a positive effect of lower fasting blood glucose. Because high blood glucose is linked to all sorts of diseases and accelerates progression of plaque formation in arteries as well, it is likely beneficial for anyone to lower their fasting blood glucose levels. Sulforaphane is still under studied but it definitely has a strong effect which is noticeable for anyone who has tried either broccoli sprout or the extract in pill form.
In my own case, the effect of sulforaphane on how I feel is positive. Whether it has any measurable effect on insulin or glucose levels would have to be studied though. At the same time we need to focus on human studies because research on cultures or in mice are not going to give an indication on the effect on humans. A large scale randomized control trial is the way to determine the effect of a supplement or treatment on the human population and while many supplements tout mouse studies, or rat studies, it's only when we have human studies that we can be sure of any effect.