(RxWiki News) Scientists believe that maintaining sufficient levels of vitamin D can lower the risk of developing multiple sclerosis (MS). But can high doses help people who already have the disease?
Australian researchers have completed the first randomized, controlled study to compare the benefits of a high dose of vitamin D compared to a low-dose supplement. The study, published in the journal Neurology, found no advantage to taking the higher dose.
"Talk to your doctor about vitamin D."
Previous studies have shown a connection between vitamin D and MS. People living closer to the equator, with more exposure to the sunlight that provides vitamin D to our bodies, have a lower risk of developing the disease.
In April 2011, another group of Australian scientists found that people who have spent time in the sun and have high vitamin D levels are less likely to be affected by multiple sclerosis.
Other studies have suggested that high-dose supplements cut relapse rates in MS patients, but the connection has not been firmly established. High doses of vitamin D over extended periods can have side effects including nausea, vomiting, poor appetite, and increases risk of developing painful kidney stones.
The researchers conducted a small study over the period of six months to find out if high doses have a beneficial effect compared to small vitamin D supplements. The 23 participants had relapsing-remitting MS, the most common type of the disease.
They all received at least 1,000 IU daily, with half of the participants receiving high-dose vitamin D2 to elevate their levels. The control group received a placebo high-dose.
The participants had their brains scanned four times throughout the study. The MRI showed no difference between the groups in the number of abnormalities that had formed after 6 months, or in the change of total volume of brain abnormalities.
37 percent of the high dose group experienced a relapse during the trial period, while none of the low-dose group experienced relapses.
The study authors conclude that larger studies are needed to confirm the results, and that higher doses might have a different effect at earlier stages in the disease. All participants had MS for at least six years.
The study was published in October 2011, and was supported by the Myer Foundation in Melbourne, Australia.