New Canadian research is shedding light on intriguing evidence that vitamin D may cut relapse for some multiple sclerosis patients.

According to research presented at the annual meeting of the American Academy of Neurology, high doses of the vitamin appear safe for patients with MS and may even lead to a reduction in disease relapses.

Dr. Jodie Burton, a neurologist at the University of Toronto, studied 25 people with relapsing-remitting multiple sclerosis, a form of the illness characterized by relapses during which new symptoms can appear or old ones resurface.

The patients were given an average of 14,000 international units (IU) of vitamin D3 a day for a year and then evaluated. Twenty-four other participants were allowed to take as much as 4,000 IU of vitamin D3 a day, though most averaged about 1,000 IU daily -- the amount recommended by many MS specialists.

Both groups also took 1,200 milligrams of calcium a day.

Burton's team found that only 14 per cent of those taking the high doses suffered relapses in their disease. In contrast, close to 40 per cent of the other MS patients relapsed. As well, those taking the high doses suffered 41 per cent fewer relapses than the year before the study began, compared with 17 per cent of those taking smaller doses.

Michel Cottier was one of the participants testing the safety of the high vitamin D dose. Before trying the treatment, Cottier would suffer an MS attack every nine months or so, in which he suddenly couldn't walk or move his arm.

"You have to stop working. You can't help your wife with the children anymore... simply, you can't use your body as you used to," he told CTV.

After the year on the high vitamin D dose, he hasn't relapsed in two and a half years, with no side effects, including no effect on calcium level abnormalities. Cottier is still taking about 6,000 IU of vitamin D a day, convinced it will ensure that his MS attacks won't return.

Dr. Paul O'Connor of MS Society of Canada said the results are positive, but they are still preliminary.

"I think the results showing that vitamin D reduces attacks... require confirmation in a properly designed study," he said.

"To me, it is extremely intriguing ... vitamin D is safe, it's cheap, and if we could show it helps patients with MS, it would be a huge step forward in making their lives easier."

The best results in the study were only observed in those who took the larger doses. People in the high-dose group were given escalating doses of the vitamin for six months, to a maximum of 40,000 IU daily. Doses were then gradually lowered over the next six months, averaging out to 14,000 IU daily for the year.

Burton advises MS patients to talk to their doctors before beginning vitamin D supplements, noting that too much of the vitamin can be harmful for people with certain medical conditions such as kidney disease.

O'Connor advises other MS patients not to take too much vitamin D, suggesting they not exceed 2,000 IU to 4,000 IU units a day until further research can prove that higher doses aren't dangerous.

Multiple sclerosis is an autoimmune disease in which the nerves of the brain and spinal cord are damaged by one's own immune system, resulting in loss of muscle control and sensation. People with MS can suffer from blurred vision, extreme fatigue, muscle stiffness and co-ordination difficulties.

Recent study has found that it is most common in countries north of the equator where inhabitants get less sunlight exposure and less vitamin D.

Recent research has found that proteins activated by vitamin D attach to a certain type of DNA, called DRB1-1501, which is believed to cause the disease.

Burton's team speculates that vitamin D reduces inflammation and stops the immune system from attacking its own cells, thereby ensuring the gene functions properly in the body.

With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip