Fiber Intake, Hand Grip Strength, and Bone Health in U.S. Older Adults

Describe potential relationships between fiber intake, hand grip strength, and bone health in older adults. Osteoporosis is prevalent among older adults, and diet is a modifiable factor in disease progression. Past research suggests fiber intake correlates with bone mineral density (BMD). Hand grip strength (HGS) is positively related to BMD. This study examined if hand grip strength (HGS) in older adults improved with fiber intake. Participants (N=36) aged 70.8 ± 5.7 years were assigned to control (n=18) or intervention groups (n=18). Intervention participants attended four nutrition sessions on increasing fruit and vegetable intake and physical activity. HGS was measured at pre and post assessments. Fiber intake was collected with 3, 3-day food logs. Physical activity, specifically metabolic equivalent of task (MET) hours per week, was measured with the International Physical Activity Questionnaire. Fiber intake and HGS relationships were evaluated using Pearson correlation and linear regression using SPSS 28.0. Fiber intake, HGS, and MET hours per week differences were assessed using t-tests. Pearson correlation showed a relationship between mean fiber intake and HGS (r=0.43, p=0.009). Regression showed 19.8% of the variation in HGS was accounted for by fiber intake (R2=0.198, p=0.018). Differences existed between groups’ mid-study MET hours per week (t(34)=-2.247, p=0.031) and between intervention pre and post maximum HGS (t(17)=-2.281, p=0.036). Fiber intake may be linked with improved HGS and indirectly with BMD. Physical activity may have influenced HGS. While the regression was underpowered, it serves as a pilot for future research. Larger studies directly measuring BMD are needed to confirm these findings.