I'm not going to get into some religious debate about real vitamin C vs ascorbic acid (do your own research!) but I'll tell you what I have noticed... First of all, I'm a pessimist when it comes to supplements and whatnot. This stuff hasn't changed my life or turned water into wine, but I have blasted through a cold that was going around in record time. My wife, her sister (a teacher - where it usually starts), and her sisters boyfriend all came down with the same thing, which means it was only a matter of time for me. This cold dogged them for at least a week, almost two. It was one of those out of action for a couple days at the peak type colds. I've been taking this steadily for a couple months now... the worst of it for me was one day, and I just felt tired. A little tired the day before, and the day after - I knew it was coming, but wow. One day, not even down hard. No Sore throat, no stuff runny nose... All I can say is: past experience is that I suffer the same as everyone else through these. Dayquil by day and Nyquil by night for about a week. Wiped out and just generally feeling horrible. This time, I felt that "I'm getting sick" feeling one day, the next I was just worn out but OK (no glaring symptoms really), and the day after I was bouncing back. Hopefully the next one passes just as quickly!