Well...where do I start? First of all, please note that I am a huge believer in the benefits of ACV for some ailments. However, in prevention of the stomach "flu"...no way. I have been habitual user of ACV for the last six months. However, I just experienced the WORST flu ever! Out of my family of four, I had the most extreme symptoms. And in fact while I was vomiting, I thought I might die from the acid burning feeling traveling up my esphogus. I am laying off the ACV for now. If it works for you..great. Not for this gal anymore!