Re: 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?

I think that is an excessive dose.

What is the maximum dose that you would consider as safe for vitamin D3 supplements?

It would be best to not exceed 2000IU daily.

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?

How much vitamin D a person will produce is dependent on various factors such as amount of melanin in the skin, amount of skin exposed, amount of UV light in the sunlight and length of exposure.  Also keep in mind that the inactive D₃ produced still has to be converted in to active D₃.  Simply getting sun exposure does not guarantee this.  The production of vitamin D3 is dependent on a properly functioning liver and in to active D3 by properly functioning kidneys.