Vitamin D supplements may increase muscle strength and improve balance, but one new investigation has found that a higher dose may not confer greater benefits, and — at least in this study — were in fact associated with greater risk and severity of falls. 

The researchers found that adults aged 70 and older who took 1,000 IU/day of vitamin D supplements did not have a lower risk of falls when compared with their peers who took a lower dose of 200 IU/day. 

Moreover, study participants who took vitamin D supplement doses of 2,000 and 4,000 IU/day were more likely to experience a fall when compared with those who took 1,000 IU/day, which is a relatively common dose for vitamin D supplements. 

In addition, participants assigned to 1,000 or more IU/day had a greater incidence of serious falls and falls with hospitalization compared with those assigned to 200 IU/day, reported study lead Lawrence Appel, M.D., MPH, of Johns Hopkins University.

“There’s no benefit of higher doses but several signals of potential harm,” Appel said. “A lot of people think if a little bit is helpful, a lot will be better. But for some vitamins, high-dose supplements pose more risks than benefits.” 

Older adults should discuss fall risk and vitamin D levels with their doctor and decide whether or not supplements will be helpful, the researchers concluded.  

The study was published in the Annals of Internal Medicine.