What's Rhonda Patrick's guidance on Vitamin D supplementation?

Rhonda Patrick recommends 5,000 IU of vitamin D3 daily as her own regimen, but emphasizes testing blood levels and adjusting the dose to the individual. She says her level stays around 50 ng/mL on that dose; she also notes that the Institute of Medicine set 4,000 IU as the upper tolerable intake. 1

• 1,000 IU effect: In people without SNPs that alter vitamin D metabolism, she says 1,000 IU typically raises blood levels by about 5 ng/mL. 2
• Testing and SNPs: Measure vitamin D before and after supplementation; genetic variants can affect conversion and make a standard dose less predictable. 3
• Hypercalcemia risk: She says hypercalcemia is extremely difficult to develop, describing the doses associated with concern as hundreds of thousands of IU daily for a long time. 4