Do you know your blood levels for D3?

The general rule is that one needs 1000IU D3 for each 10 units you need to raise.

This may vary from individual to individual, and also among those who are overweight (have more fat than others).

While there is controversy as to what level you should be at,
the research is promoting at least a level of 50.
Lab ranges in US start at 30 as normal (to prevent rickets as a basic minimum).