Vitamin D is a steroid hormone that plays critical roles in many aspects of human health. Findings from a new study suggest that vitamin D supplementation reduces the risk of developing vertigo in people who are deficient.

Vertigo is a condition characterized by the false sensation of movement, such as spinning, swaying, or tilting. The most common form of vertigo is benign paroxysmal positional vertigo (BPPV), which affects roughly one-third of all adults at least once in their lifetime. BPPV is caused when small stones called canaliths, which are located in the inner ear, dislodge and move into the semicircular canals – the area of the ear that regulates balance. The typical treatment for BPPV involves canalith repositioning maneuvers, also known as Epley maneuvers, a strategy used to relocate the inappropriately positioned canaliths.

The randomized controlled trial involved nearly 1,000 adults with confirmed BPPV who had undergone successful canalith repositioning maneuvers. Approximately half of the participants were randomly assigned to receive 400 IU of vitamin D and 500 milligrams of calcium carbonate twice a day for a year if their serum vitamin D level was lower than 20 ng/ml – a level considered deficient. The other half of the participants simply received follow-up care with no supplementation. The primary outcome was the annual recurrence rate of BPPV.

At the end of the study, participants who took the supplemental vitamin D and calcium were 24 percent less likely to develop BPPV than those who did not. Even greater reductions were seen in participants whose vitamin D levels were 10 ng/mL or less, with a 45 percent reduction in incidence. Slightly more than one-third of the participants who took the supplements had another episode of vertigo, but nearly one-half of those in the observation group had one.

These findings demonstrate that vitamin D and calcium supplementation may be beneficial in preventing vertigo, especially among people who are vitamin D deficient.

• Link to study abstract.