How high should your vitamin D level be?
How high should a healthy adult's blood vitamin D level be? Guideline bodies built their ranges around 20 to 30 ng/mL. Influencer and functional-medicine targets run 70 to 100 ng/mL.
The two cases
The guideline case
The National Academy of Medicine set sufficiency at 20 ng/mL for bone health in nearly all adults. VITAL, the largest trial (25,871 people, 2,000 IU a day, over five years), found no reduction in invasive cancer or major cardiovascular events, and no reduction in fractures, at achieved levels averaging around 40 ng/mL. The Endocrine Society's 2024 guideline moved away from routine testing and target-chasing in healthy adults.
The high-target case
Observational cohorts repeatedly show the lowest mortality and morbidity above the deficiency zone, and parathyroid hormone plateaus somewhere in the 30 to 40 ng/mL region in some datasets. That is the camp's best material, and it is association curves plus a hormone argument. No randomized trial has ever tested targeting 70 to 100 against 20 to 30 on any clinical outcome. The target is extrapolated, never tested.
Where each side overclaims
The high-target camp treats curve shapes as dosing instructions and rarely mentions that levels above 50 showed no added benefit in trial data, or that sustained levels above 100 to 150 carry real hypercalcemia risk. Some of its loudest target-setters sell testing or supplements. The guideline camp, when it overreaches, flattens genuine ancillary signals (VITAL's autoimmune finding, hazard ratio about 0.78) and the settled value of correcting actual deficiency.
Our graded bottom line
Vitamin D grades B on evidence and A on worth it in our library, at $5 to $8 a month, with a graded dose of 1,000 to 2,000 IU a day and one instruction ahead of the dose: test first, and dose to the result. Both camps agree deficiency is bad. The fight is over a target no trial has tested. Correct deficiency. Do not chase 70 to 100.
The consensus meter
The meter is set after the first round of sourced positions is reviewed. Positions below are being compiled now.
What the experts say
Quoted directly, linked to the source. We never publish a position we have not verified.
- supportive
Dave Asprey
Biohacker and author; founder of Bulletproof
“That's why I have to take 15,000 IUs a day in order to get my vitamin D levels up to where they should be. But normally that's too much, but not for my genetics.”
On A blood level target of 70 to 90 ng/mL, titrating his dose by blood testing. Source, 2020-09
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Last updated 2026-10-23. Educational information, not medical advice.