The association between dietary inflammatory properties and bone mineral density and risk of fracture in US adults

BACKGROUND/OBJECTIVES: To examine the associations of dietary inflammatory index (DII) with bone mineral density (BMD) and fracture risk in adult Americans. SUBJECTS/METHODS: The United States National Health and Nutrition Examination Survey participants during 2005-2010 were included if they had measured data on dietary intake and BMD. DII scores were calculated from estimated micro-and macronutrients from a single 24-h dietary recall. BMD was measured using dual-energy X-ray absorptiometry densitometers. Risk of fractures was obtained from participant self-report (ever) based on doctor information. Analyze of covariance and ?2-tests were employed, while accounting for the complex survey design. RESULTS: A total of 18 318 participants were included, with 51.3% (9397) being men. Age, sex, race, physical activity, smoking, C-reactive protein and body mass index-adjusted mean BMD (g/cm2) in different bodily sites significantly decreased across increasing quarters of the DII (all Po0.001). After further adjustment for calcium intake, the trend in BMD across DII quarters remained significant for total femur, femoral neck, trochanter and intertrochanter BMD (all Po0.001). Across increasing quarters of the DII, the proportion of fractures ranged from 1.1 to 1.5% for hip fracture (P = 0.02), from 7.9 to 10.5% for wrist fracture (Po0.001) and from 2.2 to 2.7% for spine fracture (P = 0.002. Prevalent wrist fractures significantly differed across DII quarters (Po0.0001), driven by high prevalence in the top quarter, while hip and spine fractures' prevalence did not vary significantly. CONCLUSIONS: The current study provides evidence suggesting a potential adverse effect of pro-inflammatory diet on bone health; which may have implications for dietary approaches for those with history of abnormal bone health complications.