Both high and low niacin intake was associated with a risk for incident hip fractures in older adults, according to study findings published in the Journal of Bone and Mineral Research.
Niacin has been shown to decrease C-reactive protein levels, but while higher levels of C-reactive protein are associated with fractures in older women, lower levels are associated with higher bone mineral density (BMD) in premenopausal and postmenopausal women. Human studies investigating the relationship of niacin intake and osteoporosis are limited and findings are conﬂicting. To date, none of the studies have included measurements of body composition. The goal of this study was to determine associations between the intake of dietary niacin and incident hip fractures, as well as dual-energy X-ray absorptiometry measurements of BMD of the hip and body composition.
The cohort comprised 5187 individuals age ≥65 who participated in the Cardiovascular Health Study. The cohort was divided into 4 quartiles based on niacin intake: 3.6 to 21.8 mg/day, 21.9 to 30.2 mg/day, 30.3 to 40.9 mg/day, and 41.0 to 102.4 mg/day. The mean daily dietary niacin intake was 32.6 mg. At a median follow-up of 13 years, 725 participants experienced an incident hip fracture, and in adjusted models, dietary niacin intake was signiﬁcantly associated with a higher risk for sustaining a hip fracture (hazard ratio [HR], 1.12; 95% CI, 1.01-1.24) and spline models suggested that there may be a U-shaped association. A post hoc analyses found that both the lowest (HR, 1.31; 95% CI, 1.04-1.66) and highest (HR, 1.53; 95% CI, 1.20-1.95) quartiles of niacin intake were associated with an increased risk for incident hip fracture compared with more moderate intake levels seen in quartiles 2 and 3. A trend for a signiﬁcant inverse association of dietary niacin intake with hip BMD (P =.06) was also observed, but there were no signiﬁcant associations with total body BMD or any body composition measures.
The researchers noted that these preliminary findings suggest that there is a weak association between dietary intake of niacin and the risk for hip fractures, but they caution that “replication in future studies in other cohorts is imperative and inclusion of measurements of urinary and blood concentrations of vitamin B3 should be considered.”
Carbone LD, Bůžková P, Fink HA, et al. Association of dietary niacin intake with incident hip fracture, BMD, and body composition: The Cardiovascular Health Study [published online January 19, 2019]. J Bone Miner Res. doi:10.1002/jbmr.3639