Dietary vitamin A, C, and E intake and subsequent fracture risk at various sites: A meta-analysis of prospective cohort studies

BACKGROUND: This study aimed to provide reliable estimates for dietary antioxidant vitamin (vitamins A, C, and E) intake and their effect on fracture risk at various sites. METHODS: The PubMed, EMBASE, and Cochrane Library databases were searched to identify prospective cohort studies published throughout October 2019. The pooled relative risk (RR) with its 95% confidence interval (CI) was calculated using a random-effects model. RESULTS: In total, 13 prospective cohort studies involving 384,464 individuals were selected for this meta-analysis. The summary RR indicated that increased antioxidant vitamin intake was associated with a reduced fracture risk (RR: 0.92; 95% CI: 0.86–0.98; P = .015). When stratified by the vitamin types, increased vitamin E intake was found to be associated with a reduced fracture risk (RR: 0.66; 95% CI: 0.46–0.95; P = .025), whereas increased vitamin A and C intake did not affect this risk. Increased antioxidant vitamin intake was associated with a reduced fracture risk, irrespective of fracture sites (HR: 0.90; 95% CI: 0.86–0.94; P < .001); however, it did not affect hip fracture risk. Furthermore, increased antioxidant vitamin intake was associated with a reduced fracture risk in men (RR: 0.81; 95% CI: 0.68–0.96; P = .017) and combined men and women (RR: 0.83; 95%CI: 0.73–0.93; P = .002); however, it did not affect fracture risk in women. CONCLUSION: Fracture risk at any site is significantly reduced with increased antioxidant vitamin intake, especially vitamin E intake and in men.