That's true when I say 'every cold' I mean one I would actually bother taking anything for. I hardly ever go to the doctors even when I probably should because most of the time they just use Dr. Google anyway.
Still very potent stuff and worth taking most of the time just less so for some viruses in my case.
Since eating more Vit D rich foods like decent quality eggs, I haven't even been sick for a year or two anyway. The statistics Joel Salatin comes out with for his eggs are pretty staggering compared to conventional.