What it is
Regulatory status: essential nutrient and dietary supplement ingredient
Mechanism evidence: human
At a glance
What it is, why people use it, the evidence, and what to know before trying it.
Why people use it
- Correct vitamin D deficiency
- Bone health
- General health support
Evidence at a glance
Vitamin D deficiency correction is established. Routine 5,000 IU/day is above the US adult upper limit and should not be presented as a universal wellness dose; measured status, diet, sun exposure and clinical context matter.
Confidence: strong
Safety & interactions
Known side effects, interactions and use limits from reviewed sources.
Chronic excess can cause hypercalcemia, kidney stones, kidney injury and soft-tissue calcification. The US adult upper limit is 4,000 IU/day for routine unsupervised intake; 5,000 IU/day exceeds it and merits individualized laboratory and clinician review.
- Hypercalcemia
- Granulomatous disease without clinician guidance
- High-dose use without monitoring
- Nausea
- Weakness
- Kidney stones
- Thiazide diuretics
- Orlistat
- Some steroids
Forms and variants
This review does not automatically apply to:
- active prescription vitamin D analogues
- vitamin D and K blends with unknown individual amounts