From the Guidelines
Your vitamin D level of 28.3 ng/mL indicates mild insufficiency, and I recommend supplementation with vitamin D3 (cholecalciferol) at a dose of 1,000-2,000 IU daily. This recommendation is based on the most recent and highest quality study available, which suggests maintaining 25-hydroxy vitamin D (25(OH)D) concentration above 20 ng/mL (50 nmol/L) 1. Take this supplement with food containing some fat to improve absorption. For most adults, a target vitamin D level is 30-50 ng/mL, so your level is slightly below the optimal range. In addition to supplementation, try to get moderate sun exposure (about 10-30 minutes several times weekly, depending on your skin tone and location) and include vitamin D-rich foods in your diet such as fatty fish, egg yolks, and fortified dairy products. Vitamin D is crucial for calcium absorption, bone health, immune function, and may play roles in mood regulation and overall health. After 3 months of supplementation, consider retesting your levels to ensure they've reached the optimal range, at which point you might adjust to a maintenance dose.
Some key points to consider:
- The Endocrine Society defines vitamin D deficiency as total serum 25-(OH)D levels of less than 50 nmol/L (<20 ng/mL) and vitamin D insufficiency as 52.5 to 72.5 nmol/L (21 to 29 ng/mL) 1.
- The Institute of Medicine recommends a daily intake of 600 IU/d for adults aged 19 to 70 years and 800 IU/d for adults older than 70 years, assuming minimal sun exposure 1.
- Supplementation with vitamin D2 50,000 units orally every month for 6 months may be considered for patients with decreased vitamin D levels and GFR 30 ml/min per 1.73 m2 1.
- However, the most recent guideline suggests maintaining 25-hydroxy vitamin D (25(OH)D) concentration above 20 ng/mL (50 nmol/L) 1, which supports the recommendation for supplementation with vitamin D3 (cholecalciferol) at a dose of 1,000-2,000 IU daily.
From the FDA Drug Label
Caution Adequate dietary calcium is necessary for response to vitamin D therapy. WARNINGS Since calcitriol is the most potent metabolite of vitamin D available, prescription-based doses of vitamin D and its derivatives should be withheld or used with caution during treatment to avoid the risk of hypercalcemia.
The patient's vitamin D level is 28.3 ng/mL, which is considered insufficient.
- The FDA drug label does not provide a specific recommendation for this vitamin D level.
- However, it emphasizes the importance of adequate dietary calcium for response to vitamin D therapy 2.
- It also warns about the risk of hypercalcemia with vitamin D and its derivatives 3. The FDA drug label does not answer the question.
From the Research
Vitamin D Level Analysis
- The given vitamin D level is 28.3 ng/mL, which is slightly below the recommended level of at least 30 ng/mL (75 nmol/L) for optimal overall health benefits of vitamin D 4.
- According to the study, increasing vitamin D intake and having sensible sunlight exposure can help maintain serum 25-hydroxyvitamin D at the recommended level 4.
Recommended Actions
- Consider increasing vitamin D intake through supplements, with a recommended daily dose of 2000 IU/day (50 mcg/day) of vitamin D3 to achieve serum 25-hydroxyvitamin D levels above 30 ng/mL 5.
- Alternatively, a daily dose between 4000 and 6000 IU of vitamin D3 can be considered to achieve serum 25-hydroxyvitamin D levels between 40 and 70 ng/mL for greater protection against many adverse health outcomes 5.
- Cholecalciferol is the recommended form of vitamin D for supplementation, as it is the most stable and potent form of vitamin D 6.
Health Implications
- Low levels of serum 25-hydroxyvitamin D have been associated with an increased risk of developing several immune-related diseases and disorders, including psoriasis, type 1 diabetes, multiple sclerosis, rheumatoid arthritis, tuberculosis, sepsis, respiratory infection, and COVID-19 4.
- Vitamin D supplementation may have variable effects on disease-specific and patient-oriented outcomes, suggesting a correlation but not a causal relationship between low vitamin D levels and disease pathogenicity 7.