What is vitamin D deficiency?
Vitamin D supports calcium absorption and bone health. Deficiency risk varies; fatigue or muscle aches alone do not prove it.
Causes, symptoms and diagnosis
1. Definition and causes Skin production with sunlight, food and supplements are sources. Low exposure, darker skin, older age or malabsorption may raise risk; sunburn is not a prevention strategy. 2. Symptoms and assessment Prolonged deficiency can weaken bone mineralization, causing rickets in children or osteomalacia in adults. Symptoms are nonspecific; 25-hydroxyvitamin D testing is interpreted in context. 3. Care and treatment Diet, safe habits and supplements depend on age and risk. Unnecessary high doses can cause high calcium and harm; dosing needs clinical context.
Warning signs and prevention
4. When to seek help Bone pain, repeated fractures or marked weakness merit assessment. Kidney disease, pregnancy or regular medicines make professional advice especially important. 5. Prevention and daily life Vitamin D foods or fortification and risk-based follow-up can help. Not everyone needs routine testing or the same supplement dose.