Vitamin D Injections
Vitamin D is a pro-hormone that supports bone integrity, immune function, mood, and overall vitality. Deficiency is common in northern climates and among those with limited sunlight exposure.
Functional vs. Conventional Vitamin D Levels
Conventional medicine typically defines Vitamin D deficiency as serum levels below
From a functional and preventive perspective, naturopathic medicine aims for a range that supports immune, mood, and musculoskeletal wellbeing, not just the absence of deficiency. Many research groups and clinical guidelines consider levels around 125–150 nmol/L to be optimal for overall health.
Your ND will review your blood work and determine a personalized target range based on your individual health status, season, and risk factors—balancing efficacy with safety.
Why Monitor Vitamin D?
- Cardiovascular health — supports healthy blood pressure and heart function
- Bone strength — helps prevent rickets, osteopenia, osteoporosis, and fractures
- Certain cancers — low vitamin D linked with increased risk (observational evidence)
- Autoimmune balance — supports healthy immune regulation
- Mood and cognition — low vitamin D associated with seasonal and depressive symptoms
We test vitamin D levels via blood work. If deficiency is detected, your ND may recommend injection therapy.
Benefits of Optimal Vitamin D
- Bone Health: enhances calcium absorption
- Immune Support: strengthens immune regulation
- Mood Balance: may improve overall wellbeing
Vitamin D Injections — Essential Information
What are Vitamin D injections?
Injections provide a direct route to restore vitamin D levels quickly and effectively when sunlight or oral absorption are insufficient. Dosing and frequency are customized to your lab results and health goals.
Who should consider Vitamin D injections?
- Individuals with confirmed vitamin D deficiency
- People with malabsorption (celiac, Crohn’s)
- Older adults (reduced skin synthesis)
- Those with limited sunlight exposure
Injection Frequency & Dosage
Frequency and dosage depend on your vitamin D levels reviewed by your ND. Injections can range from 10 000 IU to 100 000 IU per treatment, as determined by your ND based on your results and overall health.
Potential Side Effects & Monitoring
- Mild injection-site discomfort
- Occasional nausea or digestive symptoms
- Rarely, elevated calcium with excessive dosing — why follow-up testing matters
Your ND reviews your results and adjusts dosing safely.
Testing & Follow-Up
- Blood Test (25-Hydroxy Vitamin D): the gold-standard for assessing levels
- Re-testing: ensures safe, effective replenishment and maintenance
If your MD has requisitioned vitamin D blood work within the last 6 weeks, you can book a follow-up appointment to review results and determine if injections are appropriate.
If you are an existing patient and would like our clinic to requisition your vitamin D blood work, please call us for a quote. Once results are received, our team will contact you to schedule your follow-up appointment.
Ready to Check or Replenish Your Vitamin D?
Choose the option that applies to you below.
*New patients require an initial consultation to review history, labs, and determine dosing and candidacy.
Why Naturopathic Medicine Targets Higher Vitamin D Levels (125–150 nmol/L)
While conventional reference ranges classify values above 75 nmol/L as sufficient, naturopathic and functional medicine research often identifies 125–150 nmol/L as a functional “sweet spot” supporting immune balance, mental wellbeing, muscle performance, and bone metabolism.
At these concentrations, studies show improved expression of anti-inflammatory genes, enhanced innate immune defence, and more stable mood outcomes, without increased toxicity risk.
| Serum 25(OH)D (nmol/L) | Interpretation |
|---|---|
| < 75 | Deficient — higher risk of infection, low mood, bone loss |
| 75 – 100 | Adequate — meets minimal physiologic needs |
| 125 – 150 | Optimal (Functional Range) — supports immune, mood, metabolic, and bone health |
| > 250 | Above safe range — monitor for hypercalcemia |
Selected Research & References
- Vieth R. (2007). *Vitamin D toxicity, policy, and science.* Am J Clin Nutr 85(1): 6–18. → Demonstrated safety and physiologic normalcy of serum levels up to 150 nmol/L.
- Holick MF. (2007). *Vitamin D deficiency.* N Engl J Med 357(3): 266–281. → Proposed optimal health range 100–150 nmol/L for skeletal & extra-skeletal effects.
- Grant WB & Boucher BJ. (2011). *Vitamin D in health and disease: an overview.* J Am Coll Nutr 30(5): 285–292. → Found immune and inflammatory gene expression improved > 125 nmol/L.
- Cannell JJ et al. (2008). *Epidemic influenza and vitamin D.* Virology J 5: 29. → Hypothesized antiviral immune enhancement around 125–150 nmol/L.
- Bikle DD et al. (2020). *Vitamin D: new mechanistic insights.* J Bone Miner Res 35(12): 2313–2325. → Reported immunomodulatory and neuromuscular benefits plateau between 125–150 nmol/L.
- Heaney RP et al. (2003). *25-Hydroxyvitamin D and calcium absorption efficiency.* Am J Clin Nutr 77: 204–210. → Found maximal calcium absorption ≈ 125 nmol/L.
These findings are interpreted within naturopathic and functional frameworks for optimizing wellness. Individual target levels should always be assessed by your ND, with ongoing blood work and safety monitoring.