The type of vitamin C that I like to use is called Lypo-Spheric Vitamin C. It is so bio-available that mega doses can be taken without any intestinal problems. It's almost like having IV C without the IV. I found out about it, and started taking it, prior to a biological dental procedure (dead teeth - root canal teeth- removed), using the proper procedure, which also involved using IV vit. C. Now I continue to take it all the time, because I like it so much!