A Canadian study has found that enhanced blueberry juice helped manage, and even prevent, obesity and diabetes in mice - a finding researchers are hoping will lead to similar results in humans.

Researchers at the University of Montreal said they've discovered that blueberry juice transformed by a bacteria found on the skin of the fruit halted the progression of the two conditions in mice.

Pierre Haddad, a pharmacology professor at the university, said the bacteria quadrupled the amount of antioxidants in the juice - boosting what is already thought to be helpful in protecting the body against certain harmful molecules.

The researchers found the juice reduced blood sugar levels in the rodents, which is critical to the onset of both conditions.

"This has great potential," Haddad said Tuesday in Montreal. "Our discovery is major because it opens the door to a lot of possibilities for helping people with obesity and diabetes."

The group of mice was predisposed to Type 2 diabetes, a chronic condition of the pancreas that can lead to cardiovascular problems, blindness and kidney complications. It is linked to diet and can be brought on by obesity.

The researchers suspect that the fermented juice reduced the mice's caloric intake and sugar levels, helping to stop the onset of the two conditions that have become epidemic in North America.

Haddad said sugar levels in the group dropped by one-third after the mice were given the enhanced juice, made from low-bush blueberries that are grown in various parts of Canada.

About 60 per cent of the mice in the test group had normal blood sugar levels after consuming the juice, with the remaining 40 per cent registering levels indicative of diabetes.

"Consumption of fermented blueberry juice gradually and significantly reduced high blood sugar glucose levels in diabetic mice," said Tri Vuong, the study's lead author.

"After three days, our mice subjects reduced their glycemia levels by 35 per cent."

If shown to be safe for humans, it could provide an important natural tool in controlling weight and managing blood sugar levels in people who have had Type 2 diabetes for years.

Haddad said it's not yet clear why the juice prevented diabetes or helped control blood sugar levels in mice with diabetes, adding that they haven't drawn a definitive link to the juice's increased antioxidants.

He said they will do further research to see if there are any harmful effects and, if not, try to begin testing on people.

Haddad, who also works with the Aboriginal Anti-Diabetic Medicines group in Montreal, said the findings could help slow the spread of conditions that have reached epidemic rates in North America, particularly among native populations.

"The rates of diabetes have just exploded there from less than five per cent to almost one in five people in the north of Quebec," he said.

Haddad said researchers are also looking at the juice's effects on certain types of cancer and neurological conditions.