Predict 50nmol if take 600 IU of Vitamin D for 7 months (UK, ignoring BMI, etc) – June 2024

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The pharmacokinetic differences between 10- and 15-μg daily vitamin D doses

Br J Clin Pharmacol. 2024 Jun 26. doi: 10.1111/bcp.16146
Tao You 1 2 3, Nadda Muhamad 1 2 4, Joseph Jenner 1, Zhonghui Huang 3 5

Aims: The reference nutrient intake for vitamin D in people aged ≥4 years is 10 μg/day (400 IU/day) in the UK, but the recommended daily allowance is 15 μg/day (600 IU/day) for people aged 1-70 years in the USA. Here, we aim to compare the 25-hydroxyvitamin D (25(OH)D) serum concentration profiles between the 2 doses.

Methods: With world-wide trial data of adults aged ≥18 years, 45-93 kg, we constructed a minimal physiologically based pharmacokinetics model of serum concentrations of vitamin D and 25(OH)D using nonlinear mixed effects modelling. We used this model to forecast the mean, 2.5th and 97.5th percentiles for serum 25(OH)D concentrations in British adults aged ≥16 years.

Results: Our final model used bodyweight to adjust volume of each compartment and maximum clearance of 25(OH)D. No other covariate was identified. The model accurately predicted independent data from trials of a broad range of dosing regimens. We simulated British adults and showed that circulating 25(OH)D concentrations in 95% of people taking 10 μg/day for a year is predicted to reach 50 nmol/L in 32 weeks, while 97.5% of those on 15 μg/day were predicted to attain this threshold within 28 weeks.

Conclusion: Both doses are efficacious in >95% of the British population. The daily dose of 15 μg can help 97.5% of the British adults achieve 50 nmol/L serum 25(OH)D and reach the 25 nmol/L threshold in 4 weeks.
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VitaminDWiki – Response to Vitamin D - many studies

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VitaminDWiki – Predict Vitamin D category contains:

It is very difficult to predict the response to supplementation of Vitamin D, or additional sun/UV
There are a huge number of factors involved.
 
This page also has studies predicting deficiency without Vitamin D tests

Examples of 81 studies that Predict Vitamin D levels

• 96% prediction of Vitamin D less than 20ng (not general nor cost-effective) - May 2024
• Vitamin D deficiency predicted with 91% accuracy ( AI, age, paywall) - April 2024
• Predictors of low vitamin D: race, age, and BMI (confirmed now by Machine Learning) – Feb 2024
• Low Vitamin D screening with just 5 questions (for less than 12 ng) – June 2022
• Top 10 signs of Vitamin D Deficiency (9 minute Video) - Oct 2021
• Estimate Vitamin D levels based on questionnaires (12 studies) – July 2020
• Is a senior Vitamin D insufficient - a 2 minute questionnaire is 85 percent accurate – Nov 2019
• Simple Vitamin D deficiency scoring system – Feb 2016
• Toward predicting vitamin D levels without a blood test. by VitaminDWiki
• Excellent prediction of very low vitamin D in elderly from just 16 questions (analyzed by ML) – June 2017
• Quick, free, self test of vitamin D deficiency 90% chance <20 ng