Dietary diversity, multidimensional gait characteristics, and related biomarkers in older adults: a wearable sensors study

BACKGROUND: Dietary diversity plays a crucial role in maintaining physical function. This study explored the association and potential mechanisms between dietary diversity and gait characteristics measured by wearable devices in older adults. METHODS: This cross-sectional study included 861 older adults aged 60 years or above. Dietary diversity score (DDS) was assessed using a standard food frequency questionnaire. A multi-sensor gait system was used to measure periodic, kinetic, and spatiotemporal gait parameters during a 12-meter walking test. The coefficient of variation (CV) was calculated for each parameter to assess gait stability. Multivariable linear regression models were conducted to examine the relationship between DDS and gait parameters, adjusting for demographics, lifestyle factors, cognitive function, and comorbidities. RESULTS: Participants had a mean age of 70.25 ± 6.19 years, with 58.30% being female. After adjusting for all covariates, each 1-SD increase in DDS was positively associated with Z-scores of landing control force (β = 0.072, SE = 0.033, P = 0.033), foot-off angle (β = 0.076, SE = 0.033, P = 0.021), gait speed (β = 0.086, SE = 0.033, P = 0.008), step length (β = 0.068, SE = 0.031, P = 0.032), and stride length (β = 0.078, SE = 0.033, P = 0.013). Furthermore, higher DDS was negatively associated with the CVs of initial limb support time, step time, stride time, ground reaction force, landing control force, foot-off angle, gait speed, and step length (all P < 0.05). We also identified biomarkers simultaneously related to both DDS and gait characteristics, including albumin, leptin, myostatin, brain-derived neurotrophic factor, insulin-like growth factor-1, high-sensitivity C-reactive protein, interleukin-6, and glutathione reductase. CONCLUSION: Higher DDS is associated with superior kinetic and spatiotemporal gait vigor performance and enhanced gait stability. Pathways involving nutritional status, energy metabolism, inflammatory regulation, antioxidant defense, and neural function may underpin this association.