Vitamin D3 Safe Dose for Cancer Patients?

Hi Hv, I have seen recommendations for cancer patients to take lots of vitamin D3 -- 10,000 i.u. daily. Is this a safe dose considering that it is from a supplement and not from the sun? What is the maximum dose that you would consider as safe for vitamin D3 supplements?

On the other hand, they say that you can get 10,000 i.u. of vitamin D from 20 to 30 minutes of exposure to the sun. If you got all your vitamin D from sunlight, would even 20,000 i.u. daily (about an hour's worth of sunbathing) be alright? Tweet