['To assess the effectiveness of a multivitamin (MV) tablet on nutritional status, quantitative heel ultrasound (QUS), mobility, muscle strength and falls. The design comprised two groups matched on mobility levels, randomized to receive a daily MV or placebo (P) tablet for 6 months. The setting was an Australian residential care facility.', 'A total of 92 aged care residents. Serum micronutrients, body weight, QUS, rate of falls, hand grip strength, and the timed up and go test were assessed at baseline and 6 months.', 'A total of 49 participants consumed a MV and 43, a matched P for 6 months. There was a greater increase in the MV vs P group for serum 25(OH)D (mean difference+/-standard error, 33.4+/-2.6 nmol l(-1)), folate (13.4+/-2.8 nmol l(-1)), and vitamin B12 (178.0+/-40.3 pmol l(-1)) (all P<0.001). Adequate 25(OH)D concentrations (> or =50 nmol l(-1)) were found among 77% of participants in the MV group vs 10% taking P (P<0.001). Adjusting for baseline levels, the increase in QUS was greater in the MV vs P group (3.0+/-2.0 dB MHz(-1) vs -2.9+/-2.1 dB MHz(-1), respectively, P=0.041). There was a trend towards a 63% lower mean number of falls in the MV vs P group (0.3+/-0.1 falls vs 0.8+/-0.3 falls, P=0.078).'] Does multivitamin supplementation improve nutritional status and bone quality in aged care residents?