Abstract

Currently, there is no consensus on the optimal vitamin D administration in bariatric patients. The present systematic review and meta-analysis were conducted to examine the effect of vitamin D supplements on serum level of 25(OH) vitamin D in the patients undergoing bariatric surgery (BS). Random model effects were used to estimate standardized mean difference (SMD) with a 95 confidence interval (CI). Nine clinical trials were included in the meta-analysis. Vitamin D supplementation in patients undergoing BS modestly improves vitamin D status (SMD, 0.53; 95 CI, 0.28, 0.77) particularly, in the dosages above 2850 IU/day and in the patients with BMI greater than 50 kg/m2. Vitamin D supplementation was associated with prevention of raising of the PTH serum concentration and without impact on serum calcium levels. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.