Unless you are VERY healthy/clean internally, you cannot get as good of results orally as you can with an IV. Also, the IV gets it into your blood stream instantaneously, where as it takes a while to get it via your GI Tract. And, you must ingest 3 to 5 times as much orally, gram for gram. However, as you can imagine, orally is VASTLY LESS expensive and more convenient than IV.