Vitamin d once a week side effects
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Side Effects of Once-Weekly Vitamin D Supplementation
Introduction to Vitamin D Supplementation
Vitamin D is essential for bone health, immune function, and overall well-being. Supplementation is often necessary for individuals with vitamin D deficiency, especially those with limited sun exposure. However, the frequency and dosage of supplementation can influence both its efficacy and potential side effects.
Weekly High-Dose Vitamin D and Safety
Effects on Serum Levels and Safety
A study examining the effects of a weekly dose of 8400 IU vitamin D3 in older adults found that this regimen significantly increased serum 25(OH)D concentrations without causing significant adverse effects2. Similarly, another study involving a weekly dose of 50,000 IU vitamin D3 for eight weeks in adults with vitamin D deficiency reported significant increases in serum 25(OH)D levels and selected cytokines, but no serious adverse events were noted4.
Risk of Hypercalciuria
However, higher doses of vitamin D taken less frequently may increase the risk of hypercalciuria. A study comparing different supplementation regimens found that while weekly doses of up to 10,000 IU were effective and safe, a regimen involving 50,000 IU weekly followed by monthly doses raised the risk of hypercalciuria, particularly in individuals with higher BMI5. This suggests that while weekly supplementation is generally safe, very high doses may require monitoring of urinary calcium levels to prevent potential complications.
Neuromuscular Function and Tolerability
Impact on Muscle Strength and Balance
In older adults, a weekly dose of 8400 IU vitamin D3 was investigated for its effects on neuromuscular function. The study found that while serum 25(OH)D levels increased significantly, there were no significant improvements in postural stability or muscle strength compared to placebo2. Importantly, the treatment was well tolerated, with no significant differences in adverse experiences or incidences of hypercalcemia, hypercalciuria, and elevated creatinine between the treatment and placebo groups2.
Conclusion
Weekly vitamin D supplementation, particularly at doses up to 10,000 IU, is generally safe and effective in increasing serum 25(OH)D levels without significant adverse effects. However, very high doses, such as 50,000 IU weekly, may increase the risk of hypercalciuria and should be monitored closely. Overall, weekly vitamin D supplementation can be a viable option for maintaining adequate vitamin D levels, especially in populations at risk of deficiency.
Sources and full results
Most relevant research papers on this topic
Effects of a 2-Week 5000 IU versus 1000 IU Vitamin D3 Supplementation on Recovery of Symptoms in Patients with Mild to Moderate Covid-19: A Randomized Clinical Trial
Daily 5000 IU oral vitamin D3 supplementation for 2 weeks reduces the time to recovery for cough and gustatory sensory loss in patients with mild to moderate COVID-19 and suboptimal vitamin D status.
RCT
Very Rigorous Journal
Highly CitedOnce-weekly dose of 8400 IU vitamin D(3) compared with placebo: effects on neuromuscular function and tolerability in older adults with vitamin D insufficiency.
A weekly dose of 8400 IU vitamin D3 raises vitamin D levels in elderly individuals with vitamin D insufficiency, but does not significantly reduce mediolateral sway compared to placebo.
RCTVery Rigorous JournalHighly CitedPharmacokinetics of Oral Cholecalciferol in Healthy Subjects with Vitamin D Deficiency: A Randomized Open-Label Study
High-dose vitamin D supplementation quickly normalizes serum levels in healthy individuals with vitamin D deficiency, with a more refracted schedule providing higher systemic exposure.
RCTVery Rigorous JournalThe Effect of Weekly 50,000 IU Vitamin D3 Supplements on the Serum Levels of Selected Cytokines Involved in Cytokine Storm: A Randomized Clinical Trial in Adults with Vitamin D Deficiency
Vitamin D3 supplementation significantly increases serum levels of 25OHD, IL-6, IL-10, IL-1, and leptin in adults with vitamin D deficiency, but may have a potential negative effect during cytokine storms.
RCTA 250 μg/week dose of vitamin D was as effective as a 50 μg/d dose in healthy adults, but a regimen of four weekly followed by monthly doses of 1250 μg raised the risk of hypercalciuria
A 250 g/week dose of vitamin D can improve or maintain vitamin D status in healthy adults without the risk of hypercalciuria, but 24 h urinary calcium excretion should be evaluated in healthy individuals receiving weekly single doses of 1250 g (50 000 IU).
RCTVery Rigorous JournalVitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data
Vitamin D supplementation is safe and protects against acute respiratory tract infection, with stronger benefits for patients very vitamin D deficient and those not receiving bolus doses.
Meta-AnalysisVery Rigorous JournalHighly CitedClinical trial of the effects of vitamin D supplementation on psychological symptoms and metabolic profiles in maintenance methadone treatment patients
50,000IU vitamin D supplements every 2 weeks for 12 weeks improved psychological symptoms and some metabolic profiles in maintenance methadone treatment patients.
RCTAdverse events from large dose vitamin D supplementation taken for one year or longer
Long-term high-dose vitamin D supplementation did not significantly increase the risk of total adverse events or kidney stones, but there was a trend towards increased hypercalcemia and possibly hypercalciuria.
Systematic ReviewThe effects of vitamin D supplementation on wound healing and metabolic status in patients with diabetic foot ulcer: A randomized, double-blind, placebo-controlled trial.
Vitamin D supplementation for 12 weeks significantly reduced ulcer length, width, and depth, and improved glucose homeostasis in patients with diabetic foot ulcers.
RCTHighly CitedComparison of daily, weekly, and monthly vitamin D3 in ethanol dosing protocols for two months in elderly hip fracture patients.
Daily, weekly, and monthly vitamin D3 supplementation all effectively increase serum 25-hydroxyvitamin D levels in elderly hip fracture patients, with no significant differences between the three dosing frequencies.
RCT
Rigorous JournalHighly Cited