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• Karampela I, Sakelliou A, Vallianou N, Christodoulatos GS, Magkos F, Dalamaga M. Vitamin D and obesity: current evidence and controversies. Curr Obes Rep. 2021;10(2):162–180. https://doi.org/10.1007/s13679-021-00433-1. This review summarizes current evidence from meta-analyses regarding vitamin D status in obesity, weight loss and post-bariatric surgery, highlights important methodological limitations of relevant studies, and discusses potential pathophysiologic mechanisms and important controversies. The authors conclude that obesity is associated with low vitamin D status, but weight loss has little effect on improving vitamin D levels. Moreover, vitamin D supplementation is not associated with weight loss, while it has shown contradicting results after bariatric surgery.
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Chen J, Mei K, Xie L, Yuan P, Ma J, Yu P, Zhu W, Zheng C, Liu X. Low vitamin D levels do not aggravate COVID-19 risk or death, and vitamin D supplementation does not improve outcomes in hospitalized patients with COVID-19: a meta-analysis and GRADE assessment of cohort studies and RCTs. Nutr J. 2021;20(1):89. https://doi.org/10.1186/s12937-021-00744-y.
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