Which Form?
Vitamin D
Strong
consensus
Available Forms
- Vitamin D3 (cholecalciferol), NOT D2
- Hyman specifically recommends D3 with K2 for proper calcium metabolism
- Fortified foods often use the less effective D2 form
Dosage & Timing
Dosage
- 1,000-5,000 IU daily of vitamin D3 depending on baseline levels and body weight
- Hyman recommends testing levels and targeting 50-80 ng/mL
- Patrick suggests most people need supplementation given widespread deficiency
Timing
- Take with a fat-containing meal for better absorption
- Morning or midday preferred — some evidence that evening doses can interfere with melatonin production
Expert Positions
What Each Expert Says
Huberman covers vitamin D extensively through guest experts on his show, particularly Rhonda Patrick and Roger Seheult. He includes vitamin D in his foundational supplementation protocol and has dedicated episodes to sunlight's role in health — covering UVB exposure for vitamin D production, immune function, hormonal effects, and circadian rhythm. He also discusses vitamin D's role in preventing colds and flu, noting it may offer protection especially for those with low levels. His practical recommendation is to get morning sunlight exposure and supplement D3 as part of a foundational protocol.
Unlock Expert Deep Dives
See exactly which form each expert takes, why they chose it, and their reasoning with video citations.
View Full Report