Expert Answer

How much vitamin D should you take per day?

Vitamin D dosage vitamin-d essential
Based on expert consensus data from publicly available videos, not medical advice. Always consult your healthcare provider before starting, stopping, or changing any supplement.

Quick Answer

Dosing should be based on blood levels, not a fixed amount. Most experts recommend testing 25-hydroxy vitamin D and targeting 50-80 ng/mL. Common doses range from 1,000-5,000 IU/day of D3. Hyman recommends always pairing D3 with K2 for proper calcium metabolism.

3.9/5

Strong Consensus

on Vitamin D overall

What Researchers Say

Rhonda Patrick
Rhonda Patrick Strongly Agrees

Most data-driven advocate. Cites 40% lower dementia risk with D3 supplementation. Links deficiency to 5 years of accelerated biological aging.

“1,000 IUs of vitamin D generally raises people's blood levels by about five nanograms per mil”

Rhonda Patrick, on the record @ 10:30
Mark Hyman
Mark Hyman Strongly Agrees

Recommends D3 with K2 always. Targets 50-80 ng/mL blood levels. Warns that fortified foods use the less effective D2 form.

“the range I usually recommend is two to 5,000 units a day”

Mark Hyman, on the record @ 40:05
Peter Attia
Peter Attia Agrees

Takes 5,000 IU daily. Includes D3 in his personal stack. Doses based on blood monitoring. Most cautious about oversupplementation.

“I do supplement with 5,000 IU daily, and that takes me to 50 to 60”

Peter Attia, on the record @ 08:09
Andrew Huberman
Andrew Huberman Agrees

Includes D3 in his foundational protocol. Discusses UVB exposure as the natural source.

Bryan Johnson
Bryan Johnson Agrees

Includes vitamin D in his comprehensive Blueprint longevity protocol.

Detailed Answer

Unlike most supplements where a fixed dose is recommended, vitamin D dosing should be personalized based on your blood levels. The target range is 50-80 ng/mL on a 25-hydroxy vitamin D blood test.

Attia takes 5,000 IU of D3 daily, dosed based on blood monitoring. Patrick cites data showing 40% lower dementia risk and links deficiency to 5 years of accelerated biological aging.

Key protocol details: always use D3, not D2. Hyman recommends always pairing D3 with K2 to direct calcium to bones rather than arteries. Take with a fat-containing meal. Morning preferred - some evidence evening doses may interfere with melatonin.

Factors that increase your needs: darker skin, northern latitude, obesity, older age, limited sun exposure. Get a 25-hydroxy vitamin D blood test before supplementing and retest after 3 months.

Related Questions

Can you take too much vitamin D?

Yes. Hypervitaminosis D can cause hypercalcemia. Attia warns about this. Stay below 100 ng/mL and monitor blood levels.

Should you take vitamin D with vitamin K2?

Hyman strongly recommends this combination. K2 directs calcium to bones rather than arteries.

More Questions About Vitamin D

Is vitamin D3 better than D2? When should you take vitamin D? Should you take vitamin D with magnesium?

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