Figure 2. Forest plots comparing effect size for vitamin D supplementation on changes in biomarkers for studies included in the meta‐analysis.

Changes in low‐density lipoprotein (LDL; A), homeostatic model assessment of insulin resistance (HOMA‐IR; B), and high‐sensitivity C‐reactive protein (hs‐CRP; C) are reported. The gray boxes correspond with study precision, and the lines denote 95% CIs. Studies are ordered by the cumulative vitamin D dose delivered during the course of the study (vitamin D dose×duration), from lowest to highest. The asterisks and plus sign denote combinations of vitamin D with or without calcium supplementation for two different treatment arms enrolled in the same RCT. Asemi* indicates vitamin D 50 000 IU weekly+calcium 1000 mg daily whilst Asemi+ group received vitamin D 50 000 IU weekly; Foroozanfard*, vitamin D 4000 IU daily; Foroozanfard+, vitamin D 1000 IU daily; and MD, mean difference. References: Foroozanfard+ 2017, ¹¹ Yousefi Rad 2014, ¹² Ghaderi 2017, ¹³ Maktabi 2017, ¹⁴ Tabassi 2017, ¹⁵ Foroozanfard* 2017, ¹¹ Ryu 2014, ¹⁶ Sepehrmanesh 2016, ¹⁷ Asemi+ 2015, ¹⁸ Asemi * 2015, ¹⁸ Dastorani 2018, ¹⁹ Ponda 2012, ²⁰ Dalan 2016, ²¹ Rajpathak 2010, ¹⁰ Raja‐Khan 2014, ²² Sollid 2014, ²³ Jorde 2009, ²⁴ Zittermann 2009, ²⁵ Angelloti 2019, ²⁶ Jamilian 2017, ²⁷ Osati 2016, ²⁸ Seyyed 2018, ²⁹ Maktabi 2018, ³⁰ Mousa 2017, ³¹ and Zheng 2018. ³²