From the Guidelines
To increase your vitamin D level from 23 ng/mL to 60 ng/mL, I recommend taking a loading dose of 50,000 IU of vitamin D3 weekly for 8 weeks, followed by a maintenance dose of 2,000-4,000 IU daily. This approach is based on the most recent and highest quality study available, which suggests that vitamin D3 is preferred over vitamin D2 due to its longer-lasting effects on serum 25(OH)D levels 1.
When considering the dose, it's essential to note that individual responses to vitamin D supplementation vary based on factors like body weight, age, skin tone, and baseline vitamin D status. However, most adults need approximately 1,000-2,000 IU of vitamin D3 to raise blood levels by 10 ng/mL 1.
Some key points to consider when supplementing with vitamin D3 include:
- Taking vitamin D3 with a meal containing some fat to improve absorption
- Regular monitoring of blood levels to avoid both under-supplementation and excessive levels above 100 ng/mL, which could cause hypercalcemia
- Adjusting the dose as needed after 3 months on the regimen to ensure the target level is reached
- Being aware that vitamin D is fat-soluble and builds up gradually in the system, making consistent supplementation more important than rapid correction
It's also worth noting that the available forms and dosages of vitamin D may vary by country, and patient preference should be taken into account when choosing a supplementation regimen 1. Additionally, the need for calcium supplementation alongside vitamin D depends on the patient's diet, and strict vegetarians may prefer vitamin D2 over vitamin D3 due to its plant-based origin 1.
In terms of safety, the recommended upper limit of vitamin D is 2,000 IU/day according to the Food and Nutrition Board, National Research Council, National Academy of Sciences 1. However, higher doses may be necessary for individuals with severe vitamin D deficiency or certain medical conditions, and should be taken under medical supervision.
From the Research
Vitamin D3 Dosage
To correct a vitamin D level from 23 ng/mL to 60 ng/mL, the following information is relevant:
- The American Academy of Pediatrics recommends at least 400 IU per day of vitamin D from diet and supplements for infants and children to prevent vitamin D deficiency 2.
- Evidence shows that vitamin D supplementation of at least 700 to 800 IU per day reduces fracture and fall rates in adults 2.
- In persons with vitamin D deficiency, treatment may include oral ergocalciferol (vitamin D2) at 50,000 IU per week for eight weeks, followed by maintenance dosages of cholecalciferol (vitamin D3) at 800 to 1,000 IU per day from dietary and supplemental sources 2.
- There is large international consensus that vitamin D deficiency can be prevented by 400 IU of vitamin D per day and 25OHD above 30 nmol/l (12 ng/ml), but no consensus on the required daily doses or minimal 25OHD threshold for other endpoints such as fractures and falls 3.
- The majority of experts consider 800 IU/d and serum 25OHD above 50 nmol/l (20 ng/ml) as sufficient, with a minority opinion aiming for 75 nmol/l or even higher 3.
- Some studies suggest that higher doses of vitamin D may be needed to maintain optimal levels, especially in individuals with gastrointestinal and liver disorders 4.
- However, there is no specific guidance on the dose of vitamin D3 required to correct a level from 23 ng/mL to 60 ng/mL, as the optimal dosage may vary depending on individual factors such as age, health status, and genetic predisposition 5, 6.
Key Considerations
- Vitamin D status is determined by measuring the 25-hydroxyvitamin D serum concentration, but determining the accurate thresholds for vitamin D deficiency is still a matter of debate 5.
- Only individuals at risk for vitamin D deficiency should be screened, and special attention should be given to vitamin D supplementation to prevent adverse effects 5.
- Genomic technologies have revealed several hundreds of genes associated with vitamin D actions, emphasizing the potentially negative implications of modulating vitamin D intakes in the absence of complementary human genetic and genomic data 6.