The Effect of Vitamin D Supplementation on Insulin-Like Growth Factor-1: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Fatemeh Meshkini, Shima Abdollahi, Cain Clark, Sepideh Soltani

Research output: Contribution to journalArticle


There is equivocality regarding the interaction between vitamin D and insulin-like growth factor-1 (IGF-1). Thus, the aim of this study was to elucidate the effect of vitamin D supplementation on serum levels of IGF-1 by conducting a systematic review and meta-analysis of randomized controlled trials (RCTs).
PubMed, Scopus, and ISI Web of Science databases were searched up to May 2019 for RCTs that evaluated the effect of vitamin D supplementation on IGF-1 levels. Mean and standard deviation changes of IGF-1 in each treatment group were considered for analysis and pooled using random-effect model. Risk of bias for included studies was assessed by the Cochrane scale and the NutriGrade approach was applied to evaluate the quality of evidence.
Six trials (n= 773 participants) were included in the meta-analysis. Compared with control group, vitamin D supplementation yielded no significant effect on serum level of IGF-1 (weighted mean difference [WMD] = 4.66 ng/ml, 95% CIs: -6.72 to 16.03, P=0.42, I2= 74.8, P-heterogeneity= 0.001). Additionally, no meaningful changes were observed in subgroup analyses.
The evidence from the limited number of published trials does not convincingly show that vitamin D supplementation elicits any clinically relevant effects on IGF-1 levels. More high-quality studies are needed to reach a consensual conclusion in this area.
Original languageEnglish
Article number102300
Pages (from-to)(In-Press)
JournalComplementary Therapies in Medicine
Early online date7 Jan 2020
Publication statusPublished - 1 May 2020



  • Growth factor
  • Insulin-Like growth Factor-1
  • Meta-analysis
  • Vitamin D

ASJC Scopus subject areas

  • Complementary and Manual Therapy
  • Complementary and alternative medicine
  • Advanced and Specialised Nursing

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