Reality shows such as "American Idol" and "Apprentice" have almost no physical violence, but a new study suggests their rampant displays of name-calling and snarky gossiping still make for a much meaner TV-viewing experience compared with watching fictional TV shows.

The realistic portrayal of aggression on reality TV shows might even encourage viewers to imitate the non-physical aggression in real life, according to some theories. That verbal or relational aggression typically slips past TV-rating systems and media watchdog groups, which focus instead on condemning the physical violence of gunfights and fisticuffs.

"All of these reality shows would never receive a rating of violence or aggression from the current rating systems," said Sarah Coyne, a psychologist at Brigham Young University in Provo, Utah, and lead researcher on the new study.

Verbal aggression includes direct taunts or insults. By contrast, relational aggression includes more indirect attacks on social status or relationships, such as anonymous gossip-mongering or threats to end a friendship.

The study examined the 10 most popular shows from the third quarter of 2007 among the TV-viewing audience in the United Kingdom. A few American TV shows also appeared as audience favorites among the top five reality shows and top five fictional shows.

Five reality TV shows that included "American Idol" and the British versions of "Apprentice" and "Big Brother" typically showcased more acts of aggression per hour of TV than the five fictional shows, including the medical drama "ER" and the sci-fi drama "Torchwood."

The TV show with the most aggressive acts per hour, "Apprentice," included no physical acts of violence.  Such reality shows also largely outweighed fictional shows in terms of having relational aggression.

Verbal aggression represented the most frequent type of aggression by far among all the TV shows. The researchers pointed to past research that showed links between viewing verbal aggression in the media and then behaving aggressively afterward.

The "mean girls" stereotype

Coyne became interested in studying relational aggression as a young adult counselor for a fat camp. She watched the young teenage girls in her care act mean to one another after coming out of a movie theater, and she wondered if the realistic portrayal of aggression on the silver screen had influenced them.

Her new study found that both reality TV and fictional shows tended to portray females as the relational aggressors (the gossipy type) rather than males, which fits the "mean girls" stereotype.

But the TV depictions clash with reality, which shows that girls are just slightly more relationally aggressive than boys during late childhood and the early teen years. That difference disappears entirely by adulthood, according to past studies.

"Real research shows that boys are just as likely as girls to be relationally aggressive," Coyne told LiveScience. "These TV shows are kind of perpetuating stereotypes."

The sample of top reality TV and fictional shows also showed females as the more common verbal and physical aggressors, which conflicts with past studies that found males were likelier to be the bully types.

Coyne noted that none of the popular TV programs in the study included less-popular action-adventure programs, which have both more males and more physical violence. Even so, females displayed more aggression overall than expected within the studied TV shows.

Thumbs up or thumbs down

Some reality TV shows, such as "American Idol" and "Big Brother," also encouraged viewer interaction, as viewers can vote for or against participants. The study found that interactive reality shows did not show more aggression overall than non-interactive shows.

"The shows that are really interesting are the ones where you call in," Coyne explained. "Voting someone off is actually relational aggression."

A past study found that people enjoy the vengeance aspects of reality TV, where they can satisfy their need for vindication, and so an interactive show might enhance such satisfaction. Whether or not that proves cathartic or actually increases viewer aggression remains unclear.

Coyne previously found that watching indirect aggression on TV led to an increase of indirect aggression (think mean-girl gossip) among viewers.  She and her colleagues hope to study the possible impact of interactive reality shows on TV viewers in the future.

Meanwhile, Coyne urges viewers to pay more attention to the content of what they watch.

"I think if people realized the sheer amount of aggression in certain programs, they'd say 'Wait a second, maybe we don't want this all the time,'" Coyne said. She added that she has nothing against reality TV shows in particular – her husband happens to be a fan.