Oct. 2 (HealthDay News) -- A daily high-dose vitamin D supplement can reduce the risk of falls in seniors, say researchers who reviewed the findings of eight fall prevention studies involving participants aged 65 and older.

The analysis revealed that taking between 700 and 1,000 international units (IU) of supplemental vitamin D per day (vitamin D2 or D3) reduces falls by 19 percent and by up to 26 percent with vitamin D3. The beneficial effect was significant within two to five months of starting treatment, extended beyond 12 months, and was independent of age, type of dwelling, or additional calcium supplementation, the researchers noted.

The study, published in the Oct. 2 online edition of BMJ, concluded that all people aged 65 and older should take at least 700 to 1,000 IU of supplemental vitamin D a day to reduce the risk of falling. Higher doses may be even more effective, which should be explored in future studies, the researchers wrote in a news release from the journal.

Supplemental vitamin D doses of less than 700 IU per day didn't reduce falls, Dr. Heike A. Bischoff-Ferrari, director of the Center on Aging and Mobility at University Hospital Zurich, Switzerland, and colleagues, wrote.

Active forms of vitamin D didn't appear to be more effective than the 700 to 1,000 IU supplemental vitamin D, said the study authors. They added that active forms of vitamin D cost more than standard supplemental vitamin D and are associated with increased risk for hypercalcemia -- elevated calcium levels in the blood.

SOURCE: BMJ, news release, Oct. 1, 2009