Can a gross scene from TV actually take away your appetite?

Most people who are eating and see something they consider as disgusting from TV (trash,feces,worms,stray rats,porn etc) claim that it costs their appetite. I’m not sure if this is merely a popular culture. There were times when I were eating with my sister while we suddenly watch a scene of rat colony with dirty and disgusting surroundings. She said that she has lost her appetite for that but she ate her food a few moment after that anyway. It has no effect on me whatsoever,unless it’s really in front of me. I don’t correlate my food with my surroundings.

So how about you? Got any experience?