Functional benefits of ultra‑high hydrostatic pressurized brown rice on cognition, apathy, and bone health in older adults: A 12‑month randomized controlled trial

Age-related cognitive and psychological impairments are frequently accompanied by bone mineral density decline in older adults. Ultra-high hydrostatic pressurized brown rice (UBR) may support cognitive and bone health; however, the interplay between these domains remains unclear. The present randomized controlled trial aimed to examine the effects of daily UBR consumption for 12 months on cognitive function, mental health and bone status in community-dwelling older adults. In this study, 44 participants aged 65-85 years were randomly assigned to either a white rice (WR) group or a UBR group. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) and the Cognitive Assessment for Dementia, iPad version (CADi). Apathy and depressive symptoms were evaluated using the Starkstein Apathy Scale and the Zung Self-Rating Depression Scale, respectively. The calcaneal bone area ratio was assessed using quantitative ultrasound and expressed as a percentage of the young adult mean (%YAM). At 12 months, the UBR group showed significantly higher MMSE scores compared with the WR group after adjustment for baseline values and age (P=0.046), although change scores were not significantly different. CADi total scores increased and execution time decreased significantly in the UBR group (P<0.05). Apathy scores were also significantly lower in the UBR group (P=0.008). Additionally, %YAM was significantly higher in the UBR group, and partial correlations indicated significant associations between cognitive, apathy and bone health indicators. No adverse events were reported. These findings suggest that daily UBR consumption may help preserve cognitive and motivational functions and support bone health in older adults. Further investigation in larger, prospectively registered trials is warranted. This study was retrospectively registered in February 2024, at UMIN Clinical Trials Registry as UMIN000053587.