Dietary cadmium exposure and fracture incidence among men: a population-based prospective cohort study.

Cadmium is an osteotoxic metal present in food. It causes multiple fractures in those highly exposed and is associated with reduced bone mineral density at considerably lower exposures. Little is known about fracture rates following low level cadmium exposure. We assessed the associations between dietary cadmium exposure and fracture incidence. Within a population-based prospective cohort of 22,173 Swedish men we estimated individual dietary cadmium exposure using food frequency questionnaire data and levels of cadmium in food. The average intake was 19μg/day. Hazard ratios (HR) for any fracture and hip fracture were estimated using Cox’s regression. During 10 years of follow-up, we ascertained 2,183 cases of any fracture and 374 hip fractures by computerized linkage of the cohort to registry data. Multivariable-adjusted dietary cadmium intake was associated with a statistically significant 19% (HR 1·19, 95% confidence interval, CI: 1·06-1·34) higher rate of any fracture comparing highest tertile with lowest (p (trend) = <0·01). Moreover, men in the highest tertile of dietary cadmium and lowest tertile of vegetable and fruit consumption had 41% higher rate of any fracture compared to contrasting tertiles. Hip fracture rates were also higher in the highest tertile of cadmium intake, but only statistically significant among never smokers (HR 1·70, 95% CI: 1·04-2.77). Our results indicate that dietary cadmium exposure, at general population levels, is associated with an increased rate of fractures among men. This association was independent of smoking and was most pronounced among men with low vegetable and fruit consumption.