The German version of reality TV show Big Brother has attracted accusations of "shameless voyeurism" after a female contestant had her nipple pierced live.
Daniela Peter, 23, lay topless, her face twisted in pain, as she underwent the procedure without anaesthetic.
"There is one answer to this extreme, shameless voyeurism - switching off," Green party human rights spokeswoman Claudia Roth told German paper Bild.
Child protection expert Bruno Nikles warned that children could be watching.
He said: "Such mutilation should not be shown on television."
The Big Brother format, in which contestants are locked in a house and continuously filmed, has been repeated around the world.
But producers have been castigated for cajoling the "stars" into increasingly shocking activities in a bid to increase the audience.
The UK version was taken off the air briefly in June after a fight broke out and housemates threatened to kill each other.