Efficacy of vitamin D loading doses on serum 25-hydroxy vitamin D levels in school going adolescents: an open label non-randomized prospective trial

Abstract

Vitamin D deficiency (VDD) among adolescents is a major health problem in India. The aim of this study was to assess the efficacy of therapeutic/loading doses of vitamin D supplementation on serum 25-hydroxy vitamin D (25OHD) levels in vitamin D deficient adolescents. A total of 482 out of the 511 subjects recruited for the study were divided into three groups, each group receiving 60,000 IU of vitamin D3 weekly for 4, 6 and 8 weeks followed by 600 IU daily for 12 weeks, respectively. Clinical evaluation was followed by estimation of biochemical markers and serum 25OHD levels. VDD was observed in 94.8% of adolescents. All three vitamin D loading doses were equally efficacious in achieving vitamin D sufficiency >75 nmol/L (>30 ng/mL) in more than 90% subjects in the three groups. Mean 25OHD levels in groups 2 and 3 following maintenance therapy were 67.5±16.5 nmol/L (27.0±6.6 ng/mL) and 70.0±21.8 nmol/L (28.0±8.7 ng/mL), respectively. Supplementing 60,000 IU of vitamin D3 per week for 4-8 weeks, followed by 600 IU daily through fortified milk, is an effective strategy for achieving vitamin D sufficiency in Indian adolescents.