Vitamin D Deficiency Signs
50% of world population deficient. Common in covered/indoor lifestyles, northern latitudes. Optimal blood level: 30-50 ng/mL. <20 = deficient, <30 = insufficient.
Deficiency Symptoms
Bone + muscle pain, persistent fatigue, frequent infections, depression, hair loss, slow wound healing. Severe deficiency causes osteoporosis, fractures, muscle weakness.
Sources and Doses
Sun: 11AM-3PM, 15 min face+arms. Food: fatty fish, egg yolks, UV-exposed mushrooms. Supplement: 1000-2000 IU/day routine; 4000-5000 IU/day if deficient (8-12 weeks). Test 25(OH)D blood test.
- •Optimal: 30-50 ng/mL
- •Indoor lifestyle / 50+: 2000 IU/day routine
Frequently Asked Questions
Is sun enough?▼
May-September in temperate zones, possibly. Winter, indoor lifestyle, dark skin, 50+ — supplementation needed.
Scientific References
- Holick MF (2007) Vitamin D deficiency. NEJM.
This content is for general information only and does not replace medical advice. Consult your physician or a registered dietitian for personalized guidance.