Anyone ever try this? I have a friend who swears by this. She says her dad takes it every day and never gets sick and she takes it whenever she has an upset stomach and it always helps. It supposedly is used in filters and adsorbs viruses and toxins etc so I don't see why if you ingest it you can't have norovirus or food poisoning sucked up a bit. Even preventatively if someone's sick around you? Just wondering if anyone has experience with this.