If you got diarrhea from the use of Vitamin C I will assume you were taking large amounts of oral Vitamin C. This type of Vitamin C reaches a point where the bowels cannot tolerate it. Also, the cells cannot take it in and do what is necessary. The use of IV Vitamin C avoids this problem but it is not affordable to use it everyday which would mean going to the doctor everyday. Using Liposomal Vitamin C encapsulates the Vitamin C so it is encapsulated with an fatty covering - this allows it to penetrate the cells which are also fatty covered, giving you the therapeutic effect needed. When taking oral vitamin C out of 1000 mg only about 235 mg ever gets to be used. So what you thought you were getting, you were not. Only an irritable bowel. Using liposomal vitamin C every 1000 mg taken you absorb over 800 mg of it.
As others here said - get educated on what it is that you seek. You were on the right track you just needed the right type of C to do what you wanted.