lpi.oregonstate.edu/mic/vitamins/vitamin-C/supplemental-formsAs for me, I take Ester C. I started taking it years ago and just have never changed. And, it was so long ago that I can't remember why. LOL!! I do know that you take enough to just get a loose stool and then you back off just a tad. That is how you know how much your body requires and the rest is being waste.