i built up the amount i took until i couldnt take any more and got up to almost 400mg. i didnt get sick or freak out or anything, i just knew that was as far as i wanted to go then. since then, i think i could do a gram a day like Vulcanel did. when the body has been operating without an entire esential element for human health on the periodic table, the body is going to have to adjust. all the adjustments my body has made have been positive.