Get your vitamin D levels measured, ideally before and after you begin supplementing, or at the very least a month or two after you’ve started, to ensure efficacy and personalized dosing.
Aim for vitamin D blood levels between 40 to 60 nanograms per milliliter, as studies show this range is associated with the lowest all-cause mortality and longest telomeres.
If deficient (e.g., 20 ng/mL), supplement with 2,000 IUs of vitamin D3 daily to reach 30 ng/mL, or 4,000 IUs daily to reach 40 ng/mL, adjusting based on measured levels.
Strive to maintain vitamin D blood levels between 40 to 60 nanograms per milliliter, as both too low and too high levels are associated with higher all-cause mortality.
Ensure you have enough vitamin K1 and K2 to help direct absorbed calcium to bones and other tissues, preventing its accumulation in blood vessels, especially with adequate vitamin D levels.
Choose vitamin D3 supplements over vitamin D2, as D3 has been shown to be more effective at raising serum levels of 25-hydroxyvitamin D.
Take vitamin D supplements with or immediately after a meal containing some fat, or choose supplements where vitamin D is in a carrier oil (like olive oil), to slightly increase absorption and bioavailability.
Select vitamin D3 supplements that use a stable carrier oil like olive oil, avoiding oils prone to oxidation such as soybean oil.
Consider taking 4,000 IUs of vitamin D3 per day, especially if you do not get much sun, wear sunscreen, and do not have gene polymorphisms affecting vitamin D conversion.
Consider 4,000 IUs of D3 daily if not obese and getting little sun; consider 2,000 IUs daily if not obese and getting a lot of sun (e.g., in Southern California).
If you have gene polymorphisms that make your body less efficient at converting D3, you may need to significantly increase your daily dose (e.g., up to 10,000 IUs) to reach adequate levels.
If your vitamin D levels are too high (e.g., 90 ng/mL), reduce your daily supplementation (e.g., from 5,000 IUs to 2,000 IUs) to bring them into the optimal range.
Consider supplementing with vitamin D rather than relying solely on sun exposure for production, as UVB radiation causes DNA damage which contributes to aging.
Know that approximately 1,000 IUs of vitamin D3 per day can raise blood levels of vitamin D by five nanograms per milliliter.
Consider supplementing with around 50 micrograms of vitamin K2 per day, preferably from a natural natto source, as an insurance to ensure calcium goes to the right places.
Always run the information by your physician if applicable, as the podcast content is for informational purposes only and not intended as medical advice.
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