VANCOUVER - Cyclists who don't wear helmets are up to three times more likely to die from head injury, according to a Canadian report released Monday.

The report, led by a researcher of a hospital fully affiliated with the University of Toronto, was published online in the Canadian Medical Association Journal.

Dr Nav Persaud, lead author of the study and a physician in the Department of Family and Community Medicine at St Michael's Hospital, said the study was the first of its kind to show wearing a helmet prevented death.

"Previous studies have shown that wearing a helmet is effective in minor collisions," Dr Persaud said. "But this study shows that helmets prevent injuries from more serious collisions as well."

Dr Persaud and colleagues studied 129 cycling deaths between 2006 and 2010 in the Canadian province of Ontario. They compared people who had died from head injury to those that had died from other serious injuries, and then looked at how many in each group were wearing a helmet.

"Our current laws say helmets are mandatory for those under 18, but our report found 88 percent of those who died were older than 18," Dr Persaud said. "And 18 percent were over the age of 60. So, the law is missing most people."

The researchers concluded that policy changes and educational programs that increased the use of helmets while cycling may prevent deaths.

Previous study has shown one cyclist dies in Canada each week, and cycling fatalities account for more than 2 percent of traffic fatalities. Cycling safety regulations vary by jurisdiction, and controversy remains about the effectiveness of safety measures such as helmets.