1Students' Scientific Research Center,Tehran University of Medical Sciences,PO Box 14177-55331, Tehran,Iran.
2Department of Community Nutrition,School of Nutritional Sciences and Dietetics,Tehran University of Medical Sciences,PO Box 14155-6117, Tehran,Iran.
Br J Nutr. 2018 Apr;119(8):847-858. doi: 10.1017/S0007114518000430.
We aimed to systematically review available data on the association between vitamin C intake and bone mineral density (BMD), as well as risk of fractures and osteoporosis, and to summarise this information through a meta-analysis. Previous studies on vitamin C intake in relation to BMD and risk of fracture and osteoporosis were selected through searching PubMed, Scopus, ISI Web of Science and Google Scholar databases before February 2017, using MeSH and text words. To pool data, either a fixed-effects model or a random-effects model was used, and for assessing heterogeneity, Cochran's Q and I 2 tests were used. Subgroup analysis was applied to define possible sources of heterogeneity. Greater dietary vitamin C intake was positively associated with BMD at femoral neck (pooled r 0·18; 0·06, 0·30) and lumbar spine (pooled r 0·14; 95 % CI 0·06, 0·22); however, significant between-study heterogeneity was found at femoral neck: I 2=87·6 %, P heterogeneity<0·001. In addition, we found a non-significant association between dietary vitamin C intake and the risk of hip fracture (overall relative risk=0·74; 95 % CI 0·51, 1·08). Significant between-study heterogeneity was found (I 2=79·1 %, P heterogeneity<0·001), and subgroup analysis indicated that study design, sex and age were the main sources of heterogeneity. Greater dietary vitamin C intake was associated with a 33 % lower risk of osteoporosis (overall relative risk=0·67; 95 % CI 0·47, 0·94). Greater dietary vitamin C intake was associated with a lower risk of hip fracture and osteoporosis, as well as higher BMD, at femoral neck and lumbar spine.
我们旨在系统地回顾关于维生素 C 摄入量与骨密度（BMD）以及骨折和骨质疏松风险之间关联的现有数据，并通过荟萃分析总结这些信息。在 2017 年 2 月之前，通过在 PubMed、Scopus、ISI Web of Science 和 Google Scholar 数据库中搜索 MeSH 和文本词，选择了关于维生素 C 摄入量与 BMD 和骨折及骨质疏松风险的相关研究。为了汇总数据，使用固定效应模型或随机效应模型，使用 Cochran's Q 和 I 2 检验评估异质性。进行亚组分析以确定可能的异质性来源。更高的膳食维生素 C 摄入量与股骨颈（汇总 r 0·18；0·06，0·30）和腰椎（汇总 r 0·14；95 % CI 0·06，0·22）的 BMD 呈正相关；然而，在股骨颈处发现了显著的研究间异质性：I 2=87·6 %，P 异质性<0·001。此外，我们发现膳食维生素 C 摄入量与髋部骨折风险之间无显著关联（总体相对风险=0·74；95 % CI 0·51，1·08）。在研究间发现了显著的异质性（I 2=79·1 %，P 异质性<0·001），亚组分析表明研究设计、性别和年龄是异质性的主要来源。更高的膳食维生素 C 摄入量与骨质疏松症风险降低 33 %相关（总体相对风险=0·67；95 % CI 0·47，0·94）。更高的膳食维生素 C 摄入量与股骨颈和腰椎 BMD 更高、髋部骨折和骨质疏松症风险降低相关。
