Dietary fat, saturated fatty acid, and monounsaturated fatty acid intakes and risk of bone fracture: a systematic review and meta-analysis of observational studies.

Total dietary fat intake might influence the risk of fracture; however, conflicting findings have been reported to date. Moreover, the type of fatty acids is also of vital importance. We aimed to conduct a comprehensive review of the literature on the association between dietary fat intake, saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs), and the risk of fracture. PubMed and Scopus were used to conduct a comprehensive search for articles published up to 7 January 2018. To pool effect sizes, random effects models (the DerSimonian-Laird method) were applied. The Cochrane Q test was used to trace the source of between-study heterogeneity. Six studies met inclusion criteria for meta-analysis. We found no significant association between total dietary fat intake and risk of fracture (pooled effect size 1.31, 95% confidence interval (95% CI) 0.95-1.79, P = 0.09). A significant positive association was observed between SFA intake and the risk of hip fracture (pooled effect size 1.79, 95% CI 1.05-3.03, P = 0.03). There was also a significant positive association between MUFAs derived from animal sources and the risk of fracture (pooled effect size 2.29, 95% CI 1.50-3.50, P < 0.0001). Our findings showed a strong positive association between SFAs intake and risk of hip fracture. Moreover, there was a significant positive association between MUFAs derived from animal sources and the risk of fracture.