Teeth don't want to stay a constant white

My teeth were getting real yellow for a while there and now they are getting whiter. I've been oil pulling for a long time and this is my observation that they don't continually stay white. I know I had high cadmium and that is known to turn teeth yellow. I was tested quite a few months ago and the cadmium didn't show at that point. I read that the body detoxes in stages. So I think this last yellow teeth problems is my body drawing out more cadmium. I read on earth clinic website that oil pulling helps rid heavy metals. This is IMHO, but I agree with it, according to my own experience. So I feel oil pulling is still a work in progress, slow and easy but contiunous cleansing.

Good health to all.