An international research study conducted by the University of Lund in Malmö (Sweden) has found that a compound in broccoli reduces blood sugar levels in people with type 2 diabetes. According to a clinical trial that researchers presented in the Science Translational Medicine journal this week, a concentrate of this vegetable is effective in obese patients who have the deregulated disease, without presenting any significant side effects.
There are 300 million people with type 2 diabetes worldwide, as this is the most common form of diabetes. It affects mostly people over 50, and it is estimated that 20% to 25% can't control their blood sugar levels with the most widely used drug - metformin - because of its side effects. An excess of blood sugar can cause vision loss, increase risk of cardiovascular and kidney disease, and lead to the need to amputate feet or legs, according to the World Health Organization (WHO).
The liver is largely responsible for sugar increases, especially in obese patients. According to the researchers, the liver of obese people becomes insensitive to insulin, a key hormone to regulate the metabolism's sugar. Immune to the signs of insulin, the liver behaves as if the person were on a permanent fast. It manufactures sugar in large quantities to feed the remaining organs, but that sugar accumulates in the blood.
The researchers focused their efforts on finding a drug to precisely control this phenomenon. Through experiments with a computer, and then in experiments on cells and mice, scientists came up with a compound that inhibits the manufacture of sugar in the liver: sulforaphane, a substance that abounds in vegetables such as Brussels sprouts or broccoli sprouts.
The researchers then conducted a clinical trial of 103 patients with type 2 diabetes. As a source of sulforaphane, they chose a concentrate of broccoli sprouts, since they had already been tried on people to treat other diseases, such as cancer and autism, and they had not produced any side effects. During the 12-week trial, the volunteers took the concentrate on their breakfast, at a dose equivalent to 5 pounds of broccoli daily, in addition to their usual medication.
Patients who benefited most from treatment were those in whom conventional medication - metformin in most cases - failed to keep sugar at bay, and were also obese. In all other cases, the broccoli extract did not substantially affect sugar levels.
"High doses of broccoli sprout extracts can not yet be recommended to patients as treatment, as further studies are needed to see which groups would benefit the most," the researchers wrote in the article they presented in Science Translational Medicine. However, they are already working to convert broccoli concentrate into a functional food to improve blood sugar control, according to Anders Rosengren, the director of the research. "We will also study its effect on individuals at risk of developing diabetes to see if it can also be used to prevent the disease," the scientist added.
Regarding the consumption of broccoli to prevent this disease, Rosengren said that the vegetable had a much lower concentration of sulforaphane in its natural state, and that according to their data this amount would be insufficient to affect blood sugar. "Broccoli, however, is very healthy for many other reasons," he said. He also said that, since heat destroys the sulforaphane, the broccoli concentrate must be taken raw to be effective.
