title: Carotenoids and risk of fracture: a meta-analysis of observational studies.
abstract: To quantify the association between dietary and circulating carotenoids and fracture risk, a meta-analysis was conducted by searching MEDLINE and EMBASE databases for eligible articles published before May 2016. Five prospective and 2 case-control studies with 140,265 participants and 4,324 cases were identified in our meta-analysis. Among which 5 studies assessed the association between dietary carotenoids levels and hip fracture risk, 2 studies focused on the association between circulating carotenoids levels and any fracture risk. A random-effects model was employed to summarize the risk estimations and their 95% confidence intervals (CIs). Hip fracture risk among participants with high dietary total carotenoids intake was 28% lower than that in participants with low dietary total carotenoids (OR: 0.72; 95% CI: 0.51, 1.01). A similar risk of hip fracture was found for β-carotene based on 5 studies, the summarized OR for high vs. low dietary β-carotene was 0.72 (95% CI: 0.54, 0.95). However, a significant between-study heterogeneity was found (total carotene: I2 = 59.4%, P = 0.06; β-carotene: I2 = 74.4%, P = 0.04). Other individual carotenoids did not show significant associations with hip fracture risk. Circulating carotene levels had no significant association with any fracture risk, the pooled OR (95% CI) was 0.83 (0.59, 1.17). Based on the evidence from observational studies, our meta-analysis supported the hypothesis that higher dietary total carotenoids or β-carotene intake might be potentially associated with a low risk of hip fracture, however, future well-designed prospective cohort studies and randomized controlled trials are warranted to specify the associations between carotenoids and fracture.
authors.affiliation: Department of Radiotherapy, The First Affiliated Hospital of Soochow University, Suzhou Jiangsu, PR China, 215006.
authors.forename: Jiuhong
authors.initials: J
authors.lastname: Xu
authors.affiliation: School of Public Health, Medical College of Soochow University, Suzhou, Jiangsu, PR China, 215123.
authors.forename: Chunli
authors.initials: C
authors.lastname: Song
authors.affiliation: School of Public Health, Medical College of Soochow University, Suzhou, Jiangsu, PR China, 215123.
authors.forename: Xiaochao
authors.initials: X
authors.lastname: Song
authors.affiliation: Clinical Research Unit, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, PR China, 200092.
authors.forename: Xi
authors.initials: X
authors.lastname: Zhang
authors.affiliation: School of Public Health, Medical College of Soochow University, Suzhou, Jiangsu, PR China, 215123.|Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases, School of Public Health, Soochow University, Suzhou, PR China, 215123.
authors.forename: Xinli
authors.initials: X
authors.lastname: Li
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002338:Carotenoids / Q000008:administration & dosage* / Q000737:chemistry / Q000627:therapeutic use; D019587:Dietary Supplements; D005260:Female; D006620:Hip Fractures / Q000453:epidemiology* / Q000517:prevention & control; D006801:Humans; D008297:Male; D008875:Middle Aged; D064887:Observational Studies as Topic
chemical_list: D002338:Carotenoids
keywords: carotene; carotenoids; lutein/zeaxanthin; lycopene; β-cryptoxanthin