The effect of vitamin D supplementation on hemoglobin concentration: a systematic review and meta-analysis

Abstract

Aims: The purpose of this review was to investigate the effect of vitamin D supplements on hemoglobin concentration in subjects aged 17.5-68 years old; using randomized controlled trials (RCTs). Methods: Relevant RCT studies were identified from January 2000 to January 2019 by using MeSH terms in PubMed, Embase, Cochrane Library, Clinical trials, Scopus databases and gray literature. The studies were reviewed systematically, and quality assessments were evaluated by the guidelines of the Cochrane risk of bias. The effect of vitamin D supplements (n = 14) on hemoglobin concentration was considered as primary outcome, while its effects on the levels of ferritin, transferrin saturation and iron status were derived as secondary outcomes. In total, 1385 subjects with age range of 17.5 to 68 years old were examined for 3 h to 6 months; Mean (standard deviation) or median interquartile changes in the hemoglobin concentration in each treatment group was recorded for metaanalysis. Results: Fourteen RCTs met the inclusion criteria. Current study findings propose that vitamin D supplementation leads to a non-significant reduction in hemoglobin levels in subjects (17.

Correlation of VIT D3 and serum ferritin levels in anemic patients in a hospital based study.

“…25 Arabi SM et al also reported that supplementation with vitamin D had significant effect on hemoglobin and ferritin levels along with effects on transferrin saturation. 26 We also observed using Mann Whitney U Test on our skewed data to determine the difference in median of Vit D3 with Median of Serum ferritin in gender groups, and it was observed that no statistically significant difference was observed in gender groups for both the numerical variables under study, thus retain the null hypotheses. But Yoon H et al from the Korea have reported that serum vit D3 level had a negative association/ relation with the serum ferritin levels in male gender, but was positively related with serum ferritin levels in female gender.…”

Reply: “Vitamin D Supplementation in Influenza and COVID-19 Infections. Comment on: Evidence That Vitamin D Supplementation Could Reduce Risk of Influenza and COVID-19 Infections and Deaths Nutrients 2020, 12(4), 988”

“…While low-dose vitamin D supplementation was not found to increase hemoglobin concentration in short-term studies [ 11 ], high-dose vitamin D supplementation was. A clinical trial involving 30 mechanically ventilated, critically ill adults were assigned to three groups to receive a placebo, 250,000 IU vitamin D 3 , or 500,000 IU vitamin D 3 total during a five-day periods [ 12 ].…”

Efficacy of high dose versus low dose vitamin D supplementation on serum levels of inflammatory factors and mortality rate in severe traumatic brain injury patients: study protocol for a randomized placebo-controlled trial

“…According to previous observational studies, TBI patients with vitamin D deficiency had higher mortality rate and neuro-inflammation in comparison with TBI patients with vitamin D sufficiency (15,17). Also, as vitamin D deficiency is highly prevalent in critically ill patients, rapid normalization of this deficiency may be beneficial to these patients (7,22,23). For this reason, we hypothesized that rapid correction of vitamin D deficiency in TBI patients may improve inflammation and decrease mortality rate.…”