Featured article | January 2025
Vitamin D: Evidence-Based Health Benefits and Recommendations for Population Guidelines
Grant, WB et al.
Nutrients 2025, 17(2)
The article examines the broader health benefits of vitamin D, beyond its role in bone health. It critiques current guidelines for being too focused on bone health and discusses the need for optimal vitamin D levels to reduce risks of major diseases and mortality. The article emphasizes findings from cohort studies and suggests higher supplementation doses for improved health outcomes.
Discussed in the article:
- Vitamin D deficiency (serum 25(OH)D <20 ng/mL) affects around 45% of the global population, increasing the risk of autoimmune diseases, heart disease, diabetes, cancer, and severe COVID-19.
- Recommended serum 25(OH)D levels for disease prevention are 40–70 ng/mL, with 4000 IU/day of vitamin D3 needed to achieve ~50 ng/mL in most adults.
- Hypercalcemia generally does not manifest under 150 ng/mL.
- Higher vitamin D levels lower the risk of cardiovascular disease, stroke, cancer, respiratory diseases (e.g., COPD), Alzheimer’s, and type 2 diabetes.
- Vitamin D strengthens immune defenses and reduces the severity of infections, including COVID-19.
- Supplementation during pregnancy improves maternal and infant outcomes, reducing risks of gestational diabetes, pre-eclampsia, and preterm birth.
- High-dose protocols, when medically supervised, may benefit autoimmune conditions without significant toxicity.
- Racial disparities in vitamin D levels contribute to health inequalities, especially in non-Hispanic Black and Mexican American populations.
Dosing information:
- 2000 IU/day to maintain serum 25(OH)D at 30–50 ng/mL in most adults
- 4000 IU/day raises levels to ~50 ng/mL, even in mildly obese individuals
- 4000–5000 IU/day for immune function and respiratory infection prevention
- Autoimmune Diseases: 2000 IU/day lowers incidence of autoimmune diseases
- Bone health: 800 IU/day of vitamin D3 + 1000 mg/day of calcium reduces fracture risk
- Cardiovascular: 60,000 IU/month reduces cardiovascular events in at-risk patients
- Hypertension: 1600–5200 IU/day lowers blood pressure in hypertensive adults
- Metabolic Syndrome: 50,000 IU/day in high-dose therapy (with medical supervision)
- Pregnancy: 50,000 IU/week for 6–12 weeks, then 50,000 IU/month to maintain levels >40 ng/mL
“Raising serum 25(OH)D concentrations above 30 ng/mL would greatly reduce the incidence and mortality rates for 8 of the 10 leading causes of death in the U.S., as well as many other diseases and adverse pregnancy and birth outcomes.”
“Each standard deviation of 25(OH)D concentration increase was associated with a 57% reduced risk of COPD (Chronic Obstructive Lung Disease).”
