Oral vs. injected: which vitamin D boost works best for low levels?

ABSTRACT

OBJECTIVES: Vitamin D is essential for maintaining bone and mineral balance. This study aims to identify the most effective route for achieving optimal vitamin D levels (≥30 ng/mL) to support bone and mineral health. METHODS: In this open-label randomized trial, 132 participants aged 18-60 with initial serum vitamin D levels below 30 ng/mL were divided into three intervention groups daily 800 I.U. oral tablet (Group A), weekly 60,000 I.U. oral sachet (Group B), and monthly 300,000 I.U. intramuscular injection (Group C). The study assessed changes in their serum vitamin D levels at six and 12 weeks. RESULTS: The monthly intramuscular (IM) group consistently had the highest mean vitamin D levels at six weeks 38.38(±9.953) (p<0.002) and 12 weeks 48.15(±7.71) (p<0.001). Vitamin D insufficiency was reduced to 34.8 % at six weeks (p=0.434) and 6.8 % at 12 weeks (p=0.002). Notably, 100 % of the monthly IM group achieved vitamin D sufficiency at 12 weeks. CONCLUSIONS: The monthly IM route demonstrated superior effectiveness compared to tablets and sachets at both the 6-week and 12-week points. A significantly larger number of monthly IM participants achieved vitamin D sufficiency compared to the other groups.