I came here asking the same question. I was advised by Mrs. D. to stop taking the pills about 5 days prior. I didn't want there to a false spike in the numbers based on the supplement. I would do the same when I was getting injections, I would wait until the week before I was due for a shot to get my numbers tested.

It won't hurt to stop & at least if the number is high, he'll know it wasn't from taking the supplements. My number went from 505 to 1297. If I had been taking the supplements all week, I would have been worried that it jumped because I had taken them. So I at least have peace of mind that it's a true number & I can be confident that my number went up. If he's still resistant, call the Dr and ask. If he/she agrees he should stop taking them before the blood work, he wouldn't be able to argue.