Associations of ultra-processed food intake with bone mineral density and fractures in the UK Biobank

Abstract Given there is no prospective research evidence on the association between ultra-processed food (UPF) intake and human bone health, this study aimed to analyse the associations of UPF intake with bone mineral density (BMD) and risk of fractures using data from 163 855 participants in the UK Biobank. Multiple linear regression assessed BMD, and Cox regression models estimated fracture risk. Restricted cubic splines were used to evaluate non-linearity. Participants’ average age was 56·0 years, with 1097 hip fractures and 7889 all fractures recorded over 12·0 years of follow-up. Complex inverted U-shaped associations between UPF intake and BMD were found at the femur trochanter. Compared with the lowest UPF intake, the highest UPF intake was linked to a reduction in BMD at the femoral neck ( β ( se ) = −0·0061 (0·0024), P < 0·05), femur trochanter ( β ( se ) = −0·0083 (0·0024), P < 0·001), lumbar spine ( β ( se ) = −0·0114 (0·0036), P < 0·01) and total body ( β ( se ) = −0·0095 (0·0021), P < 0·001). The link was more pronounced in participants under 65 years of age and those who were underweight ( P interaction < 0·01). Per sd increment of UPF intake was linked to 10·5 % and 2·7 % higher risks of incident hip fractures (hazard ratio (HR), 95 % CI 1·105, 1·029, 1·186; P < 0·01) and all fractures (HR, 95 % CI 1·027, 1·000, 1·055; P < 0·05), respectively. Our results suggest that higher UPF intake is associated with lower BMD and increased risk of fractures captured in hospital inpatient records, highlighting the need for dietary interventions to protect bone health.