Vitamin D Deficiency: Signs, Symptoms, and How to Optimize Your Levels
Health · Oct 28, 2025 · 1 min read
If your 25-OH-D is low, here’s how to move from “deficient” to “optimal.”
Vitamin D Deficiency: Symptoms, Levels, Optimization
Why it matters, how to test, and how to raise it.
Why It Matters
- Calcium absorption & bone strength.
- Immune system balance.
- Muscle performance & fall risk.
- Mood and seasonal wellbeing.
Common Low-D Signs
Lingering fatigue, frequent illness, muscle aches, lower-back discomfort, slow wound healing, hair shedding, low mood.
Your 25-OH-D Number
| Status | ng/mL |
|---|---|
| Deficient | < 20 |
| Insufficient | 20–29 |
| Sufficient | 30–50 |
| Often Targeted | 40–60 |
Raise It Safely
Sunlight
10–30 min midday, several times weekly. Don’t burn.
Food
Fatty fish, egg yolks, fortified milks, UV mushrooms.
Supplement
D3 (often 1,000–5,000 IU/day). Take with a fatty meal; consider K2.
Check & Adjust
Test yearly (late winter is useful). Re-test ~8–12 weeks after changing habits or dose.