BACKGROUND: Benign Paroxysmal Positional Vertigo (BPPV) is the commonest cause of vertigo in older adults. Due to its high incidence in older adults presenting with falls, vestibular assessment is recommended in the World Guidelines for Falls Prevention. There is a paucity of evidence in well conducted randomised controlled trials (RCTs) to evaluate vitamin D for prevention of BPPV recurrence in relation to falls and function. AIMS: Primary outcome: does vitamin D supplementation and dietary interventions in combination with standard care impact falls, fear of falling and function in patients with BPPV. METHODS: Post hoc analyses of phase IIa single centre, placebo controlled, double blind RCT evaluating vitamin D supplementation with diet and Canalith Repositioning Procedure (CRP) [Group A] versus diet alone with CRP [Group B] in reducing BPPV recurrence rates and the consequent effects on falls and function. RESULTS: 53 participants were recruited. 14 were vitamin D replete at baseline (Group C) with remaining 39 randomised into Groups A and B. Group A had better 5x sit to stand time and 0.75 fewer clinical BPPV recurrences per one person year (P = 0.035) compared to Group B. 25% of participants who fell reported fear of falling compared to 43% in those without falls in the 12 month follow up. DISCUSSION: Vitamin D supplementation alongside standard BPPV improved 5xchair stand test and reduced BPPV recurrence. Participants without an incident fall during follow up experience fear of falling, prompting further consideration. CONCLUSION: Vitamin D replacement was associated with fewer BPPV recurrences and improved function assessed with 5x chair stand test.