The Effect of Vitamin D Supplementation on Serum Level of Insulin-Like Growth Factor 1 (IGF-1) in 5-10-Years-Old Children with Idiopathic Short Stature

Idiopathic short stature is a common cause for referral to children's endocrinology clinics. Despite the normal level of growth hormone, the level of insulin-like growth factor 1 (IGF-1) is low in some of these individuals, which is not well-defined. The aim of this study was to determine the effect of vitamin D on the level of IGF-1 in children aged 5 to 10 years with idiopathic stunting.

In a clinical trial study, 30 children aged 5-10 years with the diagnosis of idiopathic short stature were selected, and treated with 50000 vitamin D3 supplements every week for 8 weeks. Serum levels of vitamin D and IGF-1 were measured before and after intervention and compared.

Before and after intervention, mean serum levels of vitamin D were 17.03 ± 6.8 and 44.4 ± 9.2 ng/ml (P < 0.001), and mean serum level of IGF-1 were 17.9 ± 81.5 and 124.4 ± 37.4 ng/ml (P < 0.001), respectively. The level of IGF-1 significantly increased by vitamin D supplementation.

The present study showed that improvement of vitamin D deficiency led to increased level of IGF-1. It seems that in children with idiopathic short stature, the elimination of vitamin D deficiency can be effective in increased level of IGF-1.