Fruit and Vegetable Intake and Physical Activity as Predictors of Disability Risk Factors in African-American Middle-Aged Individuals.

OBJECTIVE: To investigate fruit and vegetable intake (FVI) and different dimensions of physical activity (PA) as predictors of change in disabilities and other known precursors of progressive disability in a population-based sample of African Americans.

DESIGN: Longitudinal investigation of the independent associations of reported FVI and PA with six-year changes in disabilities and other known precursors of progressive disability.

SETTING: Longitudinal study of a population-representative cohort of late middle-aged African Americans.

PARTICIPANTS: 432 cohort participants with complete information on all measures. Measurements and Analytic Approach: During wave 8 (2008), FVI was measured using 2005 Behavioral Risk Factor Surveillance System questions and PA dimensions using the Yale Physical Activity Survey (YPAS). Disability measures included basic activities of daily living (ADLs) and instrumental ADLs (IADLs); other precursors included measured gait speed, grip strength, and short physical performance battery (SPPB) and reported lower body functional limitations (LBFLs) and FRAIL scale; these were measured at wave 4 (2004) and wave 10 (2010). Residual-change score linear regression was used to identify FVI and PA factors that were independently associated with six-year changes in disability and other precursors.

RESULTS: The study cohort was less active than the YPAS-development group. Longitudinally, leisurely walking was independently associated with better ADL, IADL, grip strength, SPPB, LBFL, and frailty outcomes; standing with better IADL and SPPB; intake of vegetables other than carrots, salads, or potatoes with better grip strength and frailty; and fruit juice intake with worse grip strength and frailty.

CONCLUSIONS: In this relatively inactive cohort, leisurely walking was associated with multiple beneficial outcomes. Benefits were also seen with vegetables other than potato intake, and fruit juice intake was associated with detrimental effects. This study highlights the importance of finding strategies to help this population increase PA (especially leisurely walking) and intake of whole fruits and vegetables.