Broccoli contains an ingredient that can help those with type 2 diabetes control their blood sugar level, according to a new study – potentially providing a much-needed treatment option for millions.
A chemical in cruciferous vegetables like broccoli and sprouts called sulforaphane is thought to be responsible, having been shown to lower glucose levels in earlier lab experiments on diabetic rats.
To identify suitable compounds to examine, researchers used computer models to identify gene expression changes linked with type 2 diabetes, and then sift through thousands of chemicals that might reverse these changes.
"We're very excited about the effects we've seen and are eager to bring the extract to patients," one of the researchers, Anders Rosengren of the University of Gothenburg in Sweden, told Andy Coghlan at New Scientist.
"We saw a reduction of glucose of about 10 per cent, which is sufficient to reduce complications in the eyes, kidneys and blood."
That 10 percent average reduction was across a sample of 97 human volunteers taking part in a 12-week randomised, placebo-controlled trial. The participants who were obese and who had higher baseline glucose levels to begin with benefitted the most.
The dose was the equivalent of around 5 kilograms (11 pounds) of broccoli daily – a fair few platefuls – but the researchers say it could be adapted into a powder to add to food or drinks.
It's important to note that all but three of those taking part in the trial continued to take metformin, a drug already used to improve blood sugar regulation in people with diabetes.
However, the researchers think sulforaphane could eventually replace metformin for some patients – up to 15 percent of those with diabetes can't take metformin because of the associated risks of kidney damage.
The two chemicals take different approaches: sulforaphane suppresses the enzymes in the liver that stimulate glucose production, whereas metformin makes cells more sensitive to insulin, taking more glucose out of the bloodstream.
With more than 29 million people having type 2 diabetes in the US alone, and that number on the rise, any kind of help is going to be very welcome.
Before the human trial, the researchers also found sulforaphane was able to reduce glucose production in liver cells grown in a lab, and shift liver gene expression away from an abnormal, diseased state in diabetic rats.
Larger and more detailed studies are required before the drug can get approved for regular treatments though, and until then it's probably wise to keep your vegetable intake to a normal, healthy level.
"More research is needed to see if this repurposed drug can be used to treat Type 2 diabetes, as it was only tested in a small number of people and only helped a subset of those who are taking it," Elizabeth Robertson from Diabetes UK, who wasn't involved in the research, told New Scientist.
"For now, we recommend that people continue with the treatment prescribed by their healthcare team."
The findings have been published in Science Translational Medicine.