Effects of having low vitamin D

Vitamin D helps the body handle calcium and maintain bone and muscle function. When levels are low, some people develop tiredness, generalised weakness, muscle aches, cramps or joint pain. Bone discomfort may be vague and can be felt in the back, hips or legs. Prolonged deficiency can make bones less resilient and contribute to a stress fracture. Low mood and frequent infections may occur alongside low vitamin D, but each also has many other possible explanations. Obesity can be associated with lower vitamin D levels because vitamin D is distributed differently in body fat.

Arrange a clinical review if symptoms persist, you have risk factors for deficiency, or you have had a fracture after a minor injury. A clinician can decide whether testing is appropriate and recommend a supplement dose suited to your result, age, diet and health conditions. Use supplements only as directed; taking more does not make correction faster and excessive vitamin D can be harmful. Include dietary sources advised by your clinician and maintain safe, sensible outdoor activity.

Seek prompt medical help for sudden severe bone pain, inability to bear weight, a suspected fracture, new muscle weakness that affects walking, or confusion with persistent vomiting. These symptoms may signal a fracture, a different medical problem, or an unsafe calcium balance and should not be self-treated with extra supplements.

Ask whether your symptoms fit vitamin D deficiency, whether a blood test or bone assessment is needed, what dose and duration of supplement is suitable, and when your response should be reviewed.