Vitamin D deficiency: symptoms
Vitamin D supports calcium absorption, bone health, and has roles in immunity and muscle function. Deficiency can be silent, then appear through bone and neuromuscular signs. The pointers below rely on reference sources.
Common signs compatible with vitamin D deficiency
- Unusual fatigue, low energy; muscle cramps and aches
- Diffuse bone pain (pelvis, lower back), tenderness to pressure
- Low‑trauma fractures; in children: impaired mineralization
- Lower mood in winter (multifactorial; low sun exposure)
These signs don’t confirm deficiency. A blood test (25‑OH‑D) is the reference exam when the context is suggestive.
Who is at higher risk?
- Low sunlight exposure, strict photoprotection, darker skin at high latitudes
- Older adults, institutionalized individuals: lower cutaneous synthesis
- Malabsorption, obesity, renal/hepatic disease; certain drugs (antiepileptics, glucocorticoids) — see inducing medicines
- Pregnancy, breastfeeding: increased needs; seek medical advice for supplementation
What to do: testing, intake, and supervised supplementation
- Order 25‑OH‑vitamin D if signs/context are compatible
- Target daily intake per age/status: national benchmarks; adjust dose with a clinician
- Prefer daily/weekly schedules over massive boluses for tolerance and monitoring; watch calcium
Excess vitamin D may lead to hypercalcemia (nausea, vomiting, confusion, arrhythmias) — respect doses and check calcemia with prolonged treatment.
Simple checklist to lower risk
- Reasonable sunlight (by skin type/season) without burning
- Include dietary sources: fatty fish, fortified foods; diet alone often falls short
- Plan follow‑up when risk factors persist (older adults, malabsorption)
Mini‑FAQ
Which blood test?
25‑OH‑vitamin D is the reference; interpret per lab and clinical context.
Food or supplements?
Diet alone often falls short; supplements help, with medical follow‑up.
Bolus or daily?
Daily/weekly regimens are often preferred to large boluses for tolerance and follow‑up.
