Vitamin D3 is very safe, one of the safer ones in fact. The target levels are still have a bit of controversy but safety is well documented. Taken blindly, with

Vitamin D3 is very safe, one of the safer ones in fact. The target levels are still have a bit of controversy but safety is well documented. Taken blindly, without testing status, the conservative range is between 800iu to 2000iu daily. A weekly or monthly dose can be taken at once without issue.