What are the symptoms of severe vitamin D deficiency?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: March 26, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Severe vitamin D deficiency can cause significant health problems, including bone pain, muscle weakness, and increased risk of fractures, with common symptoms such as fatigue, bone and muscle pain, weakness, depression, impaired wound healing, hair loss, and increased susceptibility to infections. The symptoms of severe vitamin D deficiency can be categorized into:

  • Bone-related symptoms: bone pain, muscle weakness, and increased risk of fractures
  • Systemic symptoms: fatigue, weakness, depression, impaired wound healing, hair loss, and increased susceptibility to infections
  • Specific conditions: rickets in children, characterized by soft, weak bones, delayed growth, and skeletal deformities, and osteomalacia in adults, resulting in bone pain and muscle weakness 1.

Key Points to Consider

  • Vitamin D is essential for calcium absorption and bone health, and deficiency occurs when the body lacks sufficient vitamin D from sunlight exposure or dietary sources
  • Risk factors include limited sun exposure, darker skin tone, obesity, and certain medical conditions affecting absorption
  • Regular blood tests can monitor vitamin D levels during treatment to ensure they reach the normal range of 30-50 ng/mL
  • Treatment typically involves high-dose vitamin D supplementation, often 50,000 IU weekly for 6-8 weeks, followed by maintenance doses of 1,000-2,000 IU daily, with severe cases requiring medical supervision during repletion 1.

Important Considerations for Management

  • The exact threshold that defines vitamin D deficiency is not well-established, and the association between vitamin D status and health outcomes is unclear
  • Studies have suggested a decreased risk for colorectal cancer with higher 25-(OH)D levels and either an inverse or a U-shaped relationship with mortality
  • Results have varied depending on the cut point used to define deficiency, population, and setting 1.

Monitoring and Treatment

  • Regular monitoring of vitamin D levels is crucial to ensure that treatment is effective and to minimize the risk of toxicity
  • Treatment regimens may need to be tailored to specific populations, such as men and nonwhite ethnic groups, who are absent from the evidence base
  • Further studies are needed to evaluate the harms of screening for and treatment of vitamin D deficiency 1.

From the Research

Symptoms of Severe Vitamin D Deficiency

  • Symmetric low back pain
  • Proximal muscle weakness
  • Muscle aches
  • Throbbing bone pain elicited with pressure over the sternum or tibia 2

Definition and Diagnosis

  • Severe vitamin D deficiency is defined as a serum 25-hydroxyvitamin D level of less than 20 ng per mL (50 nmol per L) 2
  • Insufficiency is defined as a serum 25-hydroxyvitamin D level of 20 to 30 ng per mL (50 to 75 nmol per L) 2

Treatment and Prevention

  • Treatment may include oral ergocalciferol (vitamin D2) at 50,000 IU per week for eight weeks 2
  • Maintenance dosages of cholecalciferol (vitamin D3) at 800 to 1,000 IU per day from dietary and supplemental sources 2
  • A single oral dose of 300,000 IU vitamin D3 can raise mean 25(OH)D serum concentrations to the target mean of above 75 nmol/l at 3 months 3

Population Affected

  • Vitamin D deficiency affects persons of all ages 2
  • Over 50% of the world's population have low vitamin D (i.e., hypovitaminosis D; serum levels below 30 ng/mL) 4

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Recognition and management of vitamin D deficiency.

American family physician, 2009

Research

Calcium and vitamin D in human health: Hype or real?

The Journal of steroid biochemistry and molecular biology, 2018

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.