Practically, telling people their gut controls their mood just gives them one more thing to worry about and buy. My opponent might have a fair point, but I still figure mood comes from life, not bacteria. I do not really know how to argue it better.

My opponent makes a fair point about companies pushing products. I am not sure how to argue back, honestly. I still feel mood comes from daily life and stress, not tiny gut bugs controlling everything. It just seems like one more thing people worry about.