Table_1_Associations of Dietary Vitamin C and E Intake With Depression. A Meta-Analysis of Observational Studies.DOCX

ObjectiveThe associations of dietary vitamin C and E intake with depression remains conflicting. This meta-analysis of observational study was therefore employed to clarify the issue further.
MethodsAn extensive literature review (PubMed, Web of Science and Embase) was performed in January 2022 to identify the observational studies on the associations of dietary vitamin C and E intake with depression. The pooled relative risk (RR) of depression for the highest versus lowest dietary vitamin C and E intake category, and the weighted mean difference (WMD) of dietary vitamin C and E intake for depression versus control subjects, were calculated.
ResultsA total of 25 observational studies (91966 participants) were included in this meta-analysis. The overall multi-variable adjusted RR demonstrated that dietary vitamin C intake was inversely associated with depression (RR = 0.72, 95% CI: 0.57 to 0.91; P = 0.005). In addition, the combined WMD showed that the dietary vitamin C intake in depression was lower than that in control subjects (WMD = −11.58, 95% CI: −14.88 to −8.29; P < 0.001). Similarly, the overall multi-variable adjusted RR demonstrated that dietary vitamin E intake was negatively associated with depression (RR = 0.84, 95% CI: 0.72 to 0.98; P = 0.02). Moreover, the combined WMD showed that the dietary vitamin E intake in depression was also lower than that in control subjects (WMD = −0.71, 95% CI: −1.07 to −0.34; P < 0.001).
ConclusionThe results of this meta-analysis suggest that both dietary vitamin C and E intake is inversely associated with depression. However, due to the limited evidence, more well-designed prospective cohort studies are still needed.

研究目的：目前膳食维生素C、E摄入与抑郁症的关联研究结论仍存在分歧。本项针对观察性研究的荟萃分析旨在进一步厘清这一学术争议。

研究方法：本研究于2022年1月对PubMed、Web of Science及Embase数据库开展全面文献检索，以筛选关于膳食维生素C、E摄入与抑郁症关联的观察性研究。本研究计算了最高与最低膳食维生素C、E摄入组的抑郁症合并相对风险（relative risk, RR），以及抑郁症患者与对照受试者的膳食维生素C、E摄入的加权均数差（weighted mean difference, WMD）。

研究结果：本项荟萃分析共纳入25项观察性研究，涉及91966名受试者。经多变量校正后的总体合并相对风险显示，膳食维生素C摄入与抑郁症发病风险呈负相关（RR=0.72，95%置信区间（confidence interval, CI）：0.57~0.91；P=0.005）。此外，合并加权均数差结果表明，抑郁症患者的膳食维生素C摄入水平显著低于对照受试者（WMD=-11.58，95%置信区间（confidence interval, CI）：-14.88~-8.29；P<0.001）。同理，经多变量校正后的总体合并相对风险显示，膳食维生素E摄入与抑郁症发病风险呈负相关（RR=0.84，95%置信区间（confidence interval, CI）：0.72~0.98；P=0.02）；合并加权均数差结果同样显示，抑郁症患者的膳食维生素E摄入水平显著低于对照受试者（WMD=-0.71，95%置信区间（confidence interval, CI）：-1.07~-0.34；P<0.001）。

研究结论：本荟萃分析结果表明，膳食维生素C与E的摄入水平均与抑郁症发病风险呈负相关。但鉴于现有证据仍存在局限性，未来仍需开展更多设计严谨的前瞻性队列研究以进一步验证该结论。