Chen, Wen-YinWen-YinChenCheng, Ying-ChihYing-ChihChengChiu, Chih-ChiangChih-ChiangChiuLiu, Hsing-ChengHsing-ChengLiuHuang, Ming-ChyiMing-ChyiHuangYU-KANG TUPO-HSIU KUO2023-09-262023-09-262023-07-0710407308https://scholars.lib.ntu.edu.tw/handle/123456789/635818Clinical studies examining the effects of vitamin D on cognition have reported inconsistent results. To date, no comprehensive study has examined this effect on the basis of sample characteristics or intervention model-related factors. This systematic review and meta-analysis of randomized controlled trials investigated the effects of vitamin D supplementation on global cognitive function and specific cognitive domains. This review was preregistered in the PROSPERO database (CRD42021249908) and comprised 24 trials enrolling 7557 participants (mean age: 65.21 years; 78.54% women). The meta-analysis revealed that vitamin D significantly influenced global cognition (Hedges' g = 0.128, p = .008) but not specific cognitive domains. A subgroup analysis indicated that the effect size of vitamin D was stronger for vulnerable populations (Hedges' g = 0.414) and those with baseline vitamin D deficiency (Hedges' g = 0.480). On the basis of subgroup analyses in studies without biological flaws (Hedges' g = 0.549), we suggest that an intervention model should correct baseline vitamin D deficiency. Our results indicate that vitamin D supplementation has a small but significant positive effect on cognition in adults.enBiological flaw; Cognition; Nutrients; Randomized controlled trial; Vitamin D deficiency[SDGs]SDG3review10.1007/s11065-023-09598-z374182252-s2.0-85164205643https://api.elsevier.com/content/abstract/scopus_id/85164205643