Effect of vitamin D supplementation on pediatric bone health: a nursing-informed systematic review

Abstract Background Vitamin D is essential for pediatric bone development, yet deficiency remains a major public health concern worldwide. The optimal form, dose, and delivery of supplementation remain debated. Nurses, due to their frequent contact with children and families, are uniquely positioned to monitor adherence and provide education, but their specific contributions have not been systematically evaluated. Objective This review aimed to evaluate the effects of vitamin D supplementation on pediatric bone outcomes (BMD, fractures, rickets) and to assess the role of nurse-led interventions in promoting adherence and clinical effectiveness. Methods We conducted a systematic review following PRISMA 2020 and EQUATOR Network guidelines (PROSPERO: CRD42025637248). MEDLINE, Embase, Web of Science, Cochrane CENTRAL, and CINAHL were searched through January 31, 2025. Eligible studies included randomized controlled trials (RCTs) and prospective cohorts of children (0–18 years) receiving ≥ 3 months of vitamin D supplementation compared with placebo or no intervention. Two reviewers independently screened studies, extracted data, and assessed risk of bias (RoB 2.0, NOS). Due to heterogeneity in populations, dosages, and outcomes, findings were narratively synthesized across four domains: BMD changes, fracture outcomes, rickets prevention, and nurse-led adherence strategies. Results Thirty-five studies (25 RCTs, 10 cohorts; > 10,000 participants) were included. Vitamin D3 (200–2000 IU/day; median 800 IU) produced a mean + 4.2% (95% CI : 3.7–4.7%) increase in lumbar spine BMD (L1–L4), with the greatest effects in children aged 6–12 years and those with baseline deficiency (< 12 ng/mL). Total body less-head BMD improved modestly; fracture reduction remained inconclusive due to inconsistent designs and lack of standardized reporting. Rickets prevention was significant, with daily preventive doses of 400–1000 IU reducing incidence by ~52% (95% CI : 45–59%). Nurse-led interventions (education, counseling, follow-up reminders) improved adherence by 31% (95% CI : 28–34%), increased serum 25(OH)D by 7 ng/mL (95% CI : 6–8 ng/mL), and were more effective than physician-only protocols due to higher accessibility and continuity of patient contact. Conclusions Vitamin D supplementation, particularly vitamin D3, significantly enhances pediatric BMD and prevents rickets, though its role in fracture reduction remains unclear. Nurse-led adherence strategies provide measurable benefits and should be integrated into supplementation protocols to optimize outcomes. Future trials should standardize DXA outcome reporting, assess pubertal stage and sex differences, and compare nursing versus other healthcare-led adherence interventions.